Green chemistry: The missing element

John Warner, Babcock Institute for Green Chemistry, Wilmington, MA 01887, United StatesWarner Babcock Institute for Green Chemistry, Wilmington, MA 01887, United States

Imagine if all consumers, all retailers and all manufacturers insisted on buying and selling only non-toxic materials! The unfortunate reality is that, even if this situation were to occur, our knowledge of materials science and chemistry would allow us to provide only a small fraction of the products and materials that our economy is based upon. The way we learn and teach chemistry and materials science is for the most part void of any information regarding mechanisms of toxicity and environmental harm. Green Chemistry is a philosophy that seeks to reduce or eliminate the use of hazardous materials at the design stage of a materials process. It has been demonstrated that materials and products CAN be designed with negligible impact on human health and the environment while still being economically competitive and successful in the marketplace. This presentation will describe the history and background of Green Chemistry and discuss the opportunities for the next generation of materials designers to create a safer and more sustainable future.


Products of the Target Inquiry project: Quality inquiry materials made for and by high school teachers that stand up to student scrutiny

Ellen J. Yezierski1,, Deborah G. Herrington2.  (1) Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States  (2) Department of Chemistry, Grand Valley State University, Allendale, MI 49401, United States

The National Science Education Standards, many state science standards, and the newly released Conceptual Framework for New Science Education Standards, call on teachers to develop inquiry-based science programs. Designing such a program can be a daunting task. Three cohorts of high school chemistry teachers have completed a long-term professional development program known as Target Inquiry (TI) at Grand Valley State University. One important product of TI is a peer-reviewed collection of inquiry-based activities for high school chemistry teachers including research-based guides for students and teachers. Not only are these activities teacher-designed and teacher-tested, they have also been edited by chemistry faculty and revised based on feedback from hundreds of teachers who used the activities with more than 30,000 students around the world. An overview of the activities, several specific examples, and instructions to access them will be presented.


Chemistry and the Next Generation Science Standards (NGSS)

Melanie M Cooper, of Chemistry, Michigan State University, East Lansing, MI 48224, United States

The Next Generation Science Standards (NGSS) will be released in Spring 2013. They are based on the NRC Framework for K-12 Science Education and are the first major science and engineering standards reform initiative in almost twenty years. They reflect what we have learned in that time about how children learn and what is needed to promote deep meaningful learning for all students. The NGSS take the form of a set of performance expectations, which integrate both disciplinary core ideas and science practices. Underlying the standards is a set of crosscutting concepts that span across all the disciplines. This presentation will discuss how the standards were developed, and how chemistry core ideas are integrated within the standards. We will discuss the changes in both content and pedagogy that will be needed to address the NGSS and provide suggestions for how teachers might prepare.


A.S.P.I.R.E: A successful model for introducing project-based learning into at-risk schools and neighborhood learning centers

Brian A. Salvatore, and Physics, Louisiana State University Shreveport, Shreveport, LA 71115, United States

The After-School Program for innovation and Respect for Education (A.S.P.I.R.E.) is a professionally guided mentorship program, whereby LSUS faculty members guide college students to mentor middle and high school students in their own schools and neighborhoods. The program's curriculum emphasizes project-based learning in science, technology, engineering, and math (STEM) in some of Louisiana's most at-risk public schools and residential areas. This program is open to students 11-18 with the permission of their parents. The program's emphasis on project-based learning stands in stark contrast to how students are currently being taught in most pubic schools. We have covered a variety of scientific areas, including medicinal chemistry, embryology, aeronautics, fluorescence, alternative energy, rocketry, fuel cells, geology, nutrition, and the chemical senses. This lecture will describe the program's successes and challenges along with useful guidelines for maximizing student participation, performance, and results.


Baking powder and baking soda: An introduction to food science

Sally B Mitchell, of Chemistry, East Syracuse Minoa Central High School, East Syracuse, NY 13057, United States

This activity will introduce the science teacher to the area of food science using fun activities with baking powder and baking soda. Lab activities and teaching notes will be provided.


Molecular spectroscopy in the high school chemistry curriculum

Dick McGraw, of Molecular Spectroscopy, Thermo Scientific, San Jose, CA 95134, United States

Thermo Scientfic, sponsor of the ACS Conant Award for outstanding high school chemistry teacher, presents an innovative program for high school and college/university science teachers and chemistry instructors. Both FTIR spectrometers and UV-Vis spectrophotometer system (including teaching materials, lab experiments and all related materials) are made availabe free of charge for use in the teaching laboratory.


Energy and food: Ready-to-use resources from the Journal of Chemical Education

Laura E Slocum1,, Hillary Wilmoth2,  (1) National Cathedral School, Washington, DC 20016, United States  (2) ACS Publications, Washington, DC 20036, United States

This presentation will focus on the chemistry of food and how we get our energy from food. More importantly for teachers, it will show you how it can be integrated into the curriculum using already available teaching materials, including hands-on activities that use low-cost materials from grocery and hardware stores. Presenters will share several ready-to-use resources from the Journal of Chemical Education (JCE) related to the meeting's theme “Chemistry of Energy and Food”. These give educators an opportunity to make stronger connections for their students between the chemical world and the students' "real" world. As time permits, participants will try out a hands-on JCE Classroom Activity related to the theme.


Developing a learning progression on benefits, costs, and risks in chemical design

Steven Cullipher1,, Hannah Sevian1, Vicente Talanquer2.  (1) Department of Chemistry, University of Massachusetts Boston, Boston, MA 02125, United States  (2) Department of Chemistry and Biochemistry, University of Arizona, Tuscon, AZ 85721, United States

The ability to continue sustainable living on this planet depends on our ability to critically analyze benefits, costs and risks (BCR) of the products that we generate and the feedstocks that we use, as well as to appropriately reason about the outcomes of our decisions. The ultimate intent of our research is to uncover intermediate understandings through which learning can be deliberately directed. In this work, we present the early stage development of a learning progression that describes the evolution of implicit assumptions along core progress variables that account for relative degrees of sophistication in reasoning as students advance in their education as chemists. Qualitative analysis of pilot study data from surveys and interviews obtained from undergraduate students at two universities in the United States has uncovered domain-general and chemistry-specific progress variables. The product of this work informs our larger learning progression on chemical design.


Investigations of language comprehension on performance in general chemistry

Samuel Pazicni1,, Daniel Pyburn1, Victor Benassi2, Elizabeth Reilly2.  (1) Department of Chemistry, University of New Hampshire, Durham, NH 03824, United States  (2) Center for Excellence in Teaching and Learning, University of New Hampshire, Durham, NH 03824, United States

While mathematical ability has long been implicated as crucial for learning chemistry, language ability remains largely uninvestigated. This contribution explores correlations between language comprehension and performance in general chemistry. Structure Building, a model that describes how linguistic information is incorporated into one's existing knowledge base, guides our work. We demonstrate that comprehension ability correlates strongly with chemistry course performance. An examination of variables predicted to interact by the Structure Building Framework suggests that high comprehension ability may be sufficient to compensate for low prior knowledge. Intriguingly, our results also suggest that instruments used to measure comprehension ability and math ability are not wholly independent of one another. We also report the design and analysis of a multiple-testing intervention strategy that differentially aids those of low comprehension ability. The effect of question type (multiple choice versus elaborative interrogation) on this multiple-quizzing strategy has also been investigated.


Interactive simulation use by small groups in a large lecture setting: Student use and perceptions

Emily B. Moore1,, Timothy A. Herzog2, Katherine K. Perkins1.  (1) Department of Physics, University of Colorado Boulder, Boulder, CO 80305, United States  (2) Department of Chemistry, Weber State University, Ogden, UT 84408, United States

Interactive simulations are emerging as powerful educational tools that support student learning through scientist-like exploration and experimentation. The PhET Interactive Simulations project has developed over 30 simulations for teaching and learning chemistry. In this study, we investigate what students do when using a PhET simulation with no explicit use instructions in a large lecture environment. From analysis of mouse click data, audio recordings, and clicker question responses, we found that, during 10-minutes of exploration with a PhET simulation, students: interacted with the majority of features available; had content-focused discussions with intermittent off-topic conversations; and found use of the simulation easy and productive for learning. Results suggest possibilities for increasing the amount of effective group work in large classes using interactive simulations with minimal instructions.


Using the picoSpin NMR for undergraduate work

Sarah M Dimick Gray, of Natural Sciences, Metropolitan State University, St. Paul, MN 55106, United States

The new picoSpin NMR allows for hands-on experimentation by undergraduate students in departments unable to afford a traditional NMR. We have been working with the picoSpin NMR for the past 18 months and present some of the experiments successfully performed in both research and classroom settings as well as some of the challenges and limitations with the instrument.


Using a PicoSpin NMR spectrometer in the sophomore organic lab

Brett Mayer, John Balyeat, Allen M. Schoffstall, of Chemistry and Biochemistry, University of Colorado Colorado Springs, Colorado Springs, Colorado 80918, United States

Rationale for using a PicoSpin NMR spectrometer in the sophomore organic lab is two-fold; rapid analysis and ease of interpretation. A quick generation of NMR data for a synthetic process is desired so that every student can assess whether he or she made the desired product and in what purity. The presence of remaining starting materials or side products can also be determined so that each student can evaluate the relative success of the synthetic experiment. Also, the spectra should be interpretable for students who are just learning the basics of NMR spectroscopy in terms of the number of signals observed, the chemical shifts, the coupling patterns and the coupling constants. A brief description of the spectrometer and its use will be discussed. Student data will be presented for organic synthesis experiments leading to liquid products, which are most easily accommodated using the instrumentation.


A little introduction to NMR with a little NMR

Laura J Anna, of Chemistry, Montgomery College, Rockville, MD 20850, United States

With the acquisition of a 45MHz Picospin NMR spectrometer, students in the organic chemistry laboratory can acquire NMR spectra of liquid compounds quickly and easily with no sample preparation. The Picospin NMR spectrometer was used to teach the introductory concepts of NMR interpretation including number of signals, chemical shift, integration and multiplicity and real-time analysis of reaction products. The spectrometer was also used to quickly analyze student samples to confirm product formation in synthesis reactions. This presentation will highlight the introduction and ongoing efforts to further integrate the Picospin NMR into the introductory organic chemistry laboratory curriculum.


Incorporation of NMR spectroscopy into organic chemistry laboratory at Butler University

LuAnne McNulty,, Anne Wilson, John Esteb, Paul Morgan, Stacy O'Reilly, Adam Azman.Department of Chemistry, Butler University, Indianapolis, IN 46201, United States

Butler University has a minimum of 240 students taking organic chemistry each semester. The introduction of NMR spectroscopy into the laboratory during the second semester is difficult without the ability to run all samples during established laboratory periods. As a result, students are provided with FIDs of necessary compounds. For example, during the unknown laboratory, each student is given both proton and carbon data for a solid and a liquid unknown. They use freeware to transform the data. As the second semester laboratory progresses, students are given FIDs for all compounds possible from a given laboratory, they do the data analysis for structure determination and correlate that information to data obtained from a real GC-MS sample.


NMR as an effective and convenient tool for teaching reaction kinetics in undergraduate organic laboratory courses

John A Cramer, of Chemistry, Seton Hill University, Greensburg, Pennsylvania 15601, United States

Although a wide range of fruitful applications of NMR spectroscopy has been achieved in a wide range of scientific disciplines, the use of NMR as a pedagogic tool for teaching chemical principles to undergraduate students remains relatively unexplored. NMR spectroscopy is in fact a versatile and robust teaching tool for connecting and engaging students with the molecular world and its operative principles. This presentation will describe experiments where 60 MHz proton NMR spectroscopy is used to introduce students to reaction kinetics. Many of these experiments involve performing reactions in NMR tubes. These microscale experiments represent a safe, efficient, inexpensive, and effective means for teaching students the principles of chemical reactivity. Monitoring the progress of reactions performed in NMR tubes can be straightforwardly accomplished by measuring the areas of resolved resonances of either reactants or products with respect to time. Examples of kinetic experiments to be presented include Diels-Alder reactions and nucleophilic substitution reactions of alkyl halides.


Proton coupled 13C nmr is useful for assigning chemical shifts in substituted benzenes

Donald D Clarke, of Chemistry, Fordham University, New York, NY 10458, United States

1H decoupled 13C nmr is standard & JCH data lost. 2D [1H13C] correlation recovers some data. It fails when 1H δ's are close e.g. alkylbenzenes. Contradictory δ's for C-2 of toluene are reported. 1H coupled 13C spectra [1DC] gave a firm answer [o>m>p]. Benzonitrile has two C's with no H. 1DC distinguishes these. 3-nitrobenzonitrile has conflicting δ's in databases. 1DC settles δ's and SDBS has corrected their assignments. Basis is that on a benzene ring 1JCH [~160 Hz]>>3JCH [~10 Hz] > 2JCH [~3 Hz] > 4JCH [~1 Hz]. Latter two are not resolved. Supported in part by an NSF grant for a 300 MHz spectrometer and by a Faculty Research grant from Fordham University.


Encouraging self-discovery through in-class demonstration laboratories

Jason C Dunham, Jason W Ribblett, of Chemistry, Ball State University, Muncie, IN 47306, United States

Limitations in resources have prevented our department from offering a traditional laboratory for the non-majors introductory chemistry course. Instead, the authors have developed in-class demonstrations which provide students an opportunity to record observations and data, analyze and graph data, and formulate conclusions as a substitute for the traditional laboratory. Developed experiments cover introductory chemistry topics such as physical and chemical properties, strength of intermolecular forces and phase changes, writing balanced chemical equations, properties of ionic and molecular compounds, and water solubility of alcohols. A typical experiment requires that students record observations and data while the instructor performs the demonstration during the lecture. Once all data and observations have been recorded, students are required to analyze and/or graph their data to formulate conclusions. Each student is then required to turn in a completed lab write-up which includes all recorded data and observations, data analysis and conclusions, and answers to post-lab questions.


Integration of computational chemistry into a non-majors, general education chemistry course

Kelly R. Gallagher,, Alyson Marmet.Department of Chemistry and Biochemistry, SUNY College at Oneonta, Oneonta, New York 13820, United States

Although commonly employed in courses for science majors, computational chemistry has largely been avoided in non-majors chemistry curricula. In an effort to help students better visualize how molecular phenomena lead to macroscopic properties, we introduced computational techniques in our non-majors course. This approach taps into modern students' familiarity with digital technology and provides another avenue for discussing applications relevant to their lives. Computer models were often used in lecture and several laboratory exercises were implemented. First, basic modeling and visualization techniques were introduced via a computational activity that related molecular structure and vibrations to the greenhouse effect. A subsequent coordinated experimental and computational exercise examined solubility and hydrogen bonding in the context of melamine-based food contamination. These activities gave students an elementary experience of computational chemistry, provided an enhanced understanding of the role computational models play in modern science, and facilitated the formation of connections between personal experience and the theories discussed in class.


Materials science experiments for nonmajors

Jennifer E Mihalick, of Chemistry, University of Wisconsin Oshkosh, Oshkosh, Wisconsin 54901, United States

"Introduction to the Chemistry of Materials" is a non-majors class that teaches the chemistry behind materials that society depends on: metals, polymers, ceramics and semiconductors. The topics are of great relevance to students majoring in the humanities, since human civilizations have always depended on the available materials - stone, bronze, iron or silicon. The economic impact of materials processing and trade is of interest to business and economics majors.

The laboratory experiments for this course introduce a variety of techniques used to synthesize, process, and analyze different types of materials. Experiments will be described in which students make polyester, paint, glass, and concrete; process metals and fibers; and analyze fibers, dyes and glazes.


Experiential chemistry: A unique laboratory course for non-majors

Marc L Richard,, Jonathan Griffiths.Chemistry Program, Richard Stockton College of New Jersey, Galloway, NJ 08205, United States

The presentation of chemistry by an experiential approach can be particularly exciting for non-science majors. To a large extent, the teaching of science concentrates on the early mastery of factual material before the students are allowed to explore the interesting problems. The approach used in this course reverses this traditional pattern. Students are first presented with a series of exciting experiments and are allowed to experience the excitement of chemistry. Once their curiosity has been aroused and ask, “Why?”, they are ready to begin to work with the underlying chemical principles. Students in Experiential Chemistry work in the laboratory each day to develop an understanding of: the process of doing chemistry, the nature of chemists and chemistry, and the question asking, experimentation and communication skills essential for the practice of chemistry. The experiences, class discussions, and writing assignments give non-science students a unique and exciting introduction to chemistry.


Uptake and impacts of silver nanoparticles on Brassica rapa: A non-majors laboratory experience

Kevin M. Metz,, Stephanie E. Sanders, Anna K. Miller.Department of Chemistry, Albion College, Albion, MI 49224, United States

Nanoscience is one of the fast growing fields in science and engineering. Laboratory experiments and entire courses for science majors have been developed at the undergraduate level to study nanoscience. However, little curricular material has been deveoped for the non-majors. Here we present a semester-long laboratory sequence developed for a non-majors course, where students investigate the potential environmental impacts of nanoscience. Students synthesize and characterize silver nanoparticles using green synthetic methods. They then use the suspension of silver nanoparticles to “water” Wisconsin Fast Plants, Brassica rapa, over a three to four week period to simulate environmental exposure. Possible impacts are examined throughout the growth period, and silver uptake by the plants is quantified at the end of the growth period. This lab requires design input from the student, making it an open ended experiment. Students participating in this class reported a renewed interest in, and greter understanding of, science.


Laboratory experiments for consumer chemistry

David A. Katz, of Chemistry, Pima Community College, Tucson, AZ 85709, United States

An integrated lecture-laboratory consumer chemistry course has been taught by this author since 2004. The course, which is Internet based, uses a series of experiments dealing with common materials that have been developed or modified from other sources in the areas of soaps and detergents, food chemistry, water chemistry, cosmetics and personal care items, over-the-counter drugs, polymers, metals, nanotechnology, dyes, papermaking, and artist materials. Although these were aimed at the non-major students, some of the experiments are now being incorporated into the general chemistry course.


First-year writing seminar on science in art and archaeology

Christopher J Stromberg, of Chemistry and Physics, Hood College, Frederick, MD 21701, United States

This talk describes a first-year seminar on Science in Art and Archaeology. The goals of the first-year seminars at Hood College are to increase writing skills and information literacy in our first-year students and to help them with the adjustment to college-level work expectations. Each week, we cover a scientific technique used in art and archaeology. On Mondays we cover the technique itself, including the basic chemical principles underlying it. These periods often include demonstrations, including a series of studies on home-made paintings using multi-spectral imaging and IR and Raman spectroscopy. On Wednesdays we discuss a paper that used the week's techniques to solve real problems in art and archaeology. Multiple writing assignments are given throughout the semester including weekly literature reviews and homework sets, two three-page papers, and one 8-10 page research paper. Through this course, students are exposed to interesting applications of science and reading the scientific literature.


Catching criminals with chemistry: A non-majors course in forensics

William S. Case, of Chemistry, University of Richmond, Richmond, VA 23173, United States

Forensics has awakened a heightened interest in science among society at large. At the university level, forensics provides a wonderful way to engage non-majors in a scientific setting. At the University of Richmond we have created a non-majors chemistry course entitled "Catching Criminals with Chemistry." The course teaches students how chemistry can be applied to solving crimes. The nature of physical evidence is discussed, along with the chemical techniques used to gather and analyze that evidence. The course also introduces students to the legal aspects surrounding the introduction of evidence in court, thus providing an interdisciplinary focus for those interested in science and law. By combining case studies with applicable technology in the laboratory, students gain a heightened understanding of the important roles that chemistry plays in forensics. More importantly, non-majors leave the course with a solid understanding of a vast array of chemical instrumentation.


Using milk and cheese to demonstrate food chemistry

Michael H. Tunick, & Functional Foods Research Unit, U.S. Department of Agriculture, ARS, ERRC, Wyndmoor, PA 19038, United States

Students usually do not realize how much chemistry is involved in making a food like cheese, and teachers may use milk and cheese to reveal some interesting principles. Cheese is made by lowering the pH of milk, coagulating the protein with enzymes, and removing the whey with heat and pressure. The huge array of cheese in the world results from variations in the procedures, leading to different chemical reactions in the curd during processing and storage. Chemical principles are demonstrated with some simple experiments, such as acidifying milk to precipitate casein (demonstrating the isoelectric point) and heating different varieties to compare how far they stretch and the amount of oil coming off (illustrating the importance of the physical state of the protein matrix). Related experiments include adding drops of milk to a glass of water to illustrate light scattering. Experimentation with common foods such as milk and cheese ought to elevate a classroom's interest in chemistry.


Reaching the non-traditional student population via math primers in a freshman chemistry lab course

Meagan K. Mann,, C. Drew Carrico.Department of Chemistry, Austin Peay State University, Clarksville, Tennessee 37044, United States

At schools with a high non-traditional student population, the basic arithmetic involved in freshman chemistry is often a major source of frustration and confusion as students try to recall information from math courses they took five or more years before. This often leads to students doing poorly in the course as they try to learn chemistry calculations while not fully understanding the arithmetic involved. Presented here is a lab redesign for a non-majors chemistry course that incorporates math primers with the pre-lab materials to help students get a step-by-step guide on how to answer problems that are present in both lecture and lab. A comparison and assessment of these new labs as compared to the previously used, traditional format labs is included.


Tandem cross-coupling/electrocyclization cascades: A modular strategy

Katerina P. Hilleke,, David A. Vosburg.Department of Chemistry, Harvey Mudd College, Claremont, CA 91711, United States

This talk will describe a unified synthetic strategy for the synthesis of beilschmiedic acid C, endiandramide A, erythrophloin C, and related bioactive natural products. In each case, acyclic building blocks have been joined in a Stille cross-coupling reaction that triggered two electrocyclization reactions. The resulting bicyclo[4.2.0]octadiene products can be further manipulated to generate both natural and unnatural products.


Synthesis of tripodal CMPO compounds for heavy metal chelation

Michael T Peruzzi1,, Eric J Werner2, Shannon M Biros1.  (1) Department of Chemistry, Grand Valley State University, Allendale, MI 49401, United States  (2) Department of Chemistry, Biochemistry and Physics, The University of Tampa, Tampa, FL 33606, United States

Heavy metal chelation has a wide variety of applications including nuclear waste remediation, MRI contrast agents, and chelation therapy. The TRUEX nuclear waste remediation process currently employs carbamoylmethyl phosphine oxides (CMPOs) as bidentate chelation agents to remove heavy, f-series metals from spent nuclear fuel. However, single CMPO units are promiscuous in their selectivity and many metals require a greater denticity than provided by three solitary CMPOs. Our lab is currently interested in organizing CMPO units on a tripodal cap to take advantage of the chelate effect. We are also interested in derivatizing these ligands to increase the affinity and selectivity of metal binding. Current efforts toward the synthesis of these compounds will be discussed.


Towards a rational design of a better tetracycline: Understanding zinc binding interactions in tetracycline

Evan L Flores,, Sabrina G Sobel, Tim Leimbach.Department of Chemistry, Hofstra University, Hempstead, New York 11549, United States

Matrix metalloproteinases (MMPs) are known to cause acne and periodontal disease and have been implicated in cancer through remodeling of the surrounding tissues to enable tumor growth. MMPs have an essential zinc(II) ion as part of the active site. Tetracycline and analogues are known to be effective treatments for acne and periodontal disease. One hypothesis involves the complexation of Zn(II) ions, thus reducing the availability of free Zn(II) in the extracellular environment for use by MMPs; tetracycline does not competitively inhibit MMPs with zinc already bound. The binding mode of tetracycline with metal ions has only been speculated.

This exploratory work aims to test tetracycline and its coordination with Zn(II) ions. Titration methods show the stoichiometry of tetracycline to zinc in a biologically relevant, pH-controlled environment. Molecular modeling provides insight into tetracycline's coordination to Zn(II). By understanding tetracycline's binding mode, we can further the efficacy of this class of molecules.


Synthesis and biological testing of biotinylated dione-coupled platinum complexes

Katie J. Bitting1,, Abraham L. Yousef1, Robin L. Davies2, Robert Granger1.  (1) Department of Chemistry, Sweet Briar College, Sweet Briar, VA 24595, United States  (2) Department of Biology, Sweet Briar College, Sweet Briar, VA 24595, United States

Many cancer cells over-express receptors for certain vitamins such as folic acid and biotin, therefore attaching one of these vitamins to a cytotoxic compound (e.g. cisplatin) is a potential method for designing useful chemotherapeutic agents with increased selectivity and cellular uptake. The research presented herein will detail our work towards the synthesis of biotinylated imidazophenanthroline and dipyridophenazine-based platinum complexes. Synthetic strategies for the coupling of 1,10-phenanthroline-5,6-dione to 4-acetylaminobenzaldehyde and 1,2,4-triaminobenzene compounds will be discussed along with an EDC-mediated biotin coupling scheme. The bioactivities of the compounds against HCT-15 cancer cells will be explored and the results presented and discussed.


Four-step, stereoselective synthesis of artemone

Brian C. Fielder,, David A. Vosburg.Department of Chemistry, Harvey Mudd College, Claremont, CA 91711, United States

Artemone is an antifungal natural product from the Indian sage Artemisia pallens. We have developed a direct, four-step synthetic route from (-)-linalool that features a stereoselective cyclization with an organocatalyst. This synthesis uses no protecting groups, minimizes redox manipulations, and seeks to maximize atom economy.


Progress towards the synthesis of the repeating pentasaccharide unit of pneumococcal serotype 31

Nicole L Snyder1, Makenzie K Treible1,, Connor W Brown2, Alexander D Thompson2, Megan A Schlosser2.  (1) Department of Chemistry, Davidson College, Davidson, NC 28035, United States  (2) Unaffiliated, United States

Streptococcus pneumonia-based invasive pneumococcal disease (IPD) is one of the leading causes of illness in adults and children worldwide. Streptococcus pneumoniae are identified by capsular polysaccharide cell surface markers (serotypes) that are distinguished by their chemical structure and antigenicity. Today, over 90 different serotypes are known to exist. Advances in science and technology over the past 70 years have led to the development several vaccines based on capsular polysaccharide isolates. Combined, these vaccines account for 23 of the over 90 known serotypes. As part of our ongoing efforts to augment existing vaccines, our group has been focusing on synthesis of the repeating pentasaccharide unit of pneumococcal serotype 31 or PS31. Herein we report on our ongoing efforts to overcome several of the synthetic challenges en route to PS31, including the incorporation of galactofuranose residues substituted at the C3 position and two β-rhamnosidic linkages.


Synthesis of a phosphorylated, lipid-linked inositol glycan as a potential anti-cancer agent

Vanessa Ruiz,, Marc d'Alarcao.Department of Chemistry, San Jose State University, San Jose, CA 95192, United States

Inositol glycans (IGs) are naturally occurring, phosphorylated, inositol-containing carbohydrates that are released by insulin-sensitive cells in response to insulin. IGs can activate pyruvate dehydroganase phosphatase, thus stimulating aerobic metabolism. Cancer cells are known to switch from aerobic metabolism to anaerobic metabolism even in the presence of oxygen, a phenomenon known as the Warburg effect. This is thought to enable cancer cells to evade intrinsic apoptosis. Our goal is determine if a synthetic IG competent to stimulate aerobic metabolism in cancer cells, thus reversing the Warburg Effect, can cause the cells to undergo apoptosis. Our target compound is a pseudodisaccharide comprised of 2-glucosaminyl-alpha1,6-myo-inositol containing a 16-carbon lipid chain and a phosphate group. Progress toward the chemical synthesis and biological evaluation of this IG as an anticancer agent will be described.


Phospholipid remodeling as a pharmaceutical target against Candida albicans

Mariam Ayyash,, Amal Algahmi, Peter Oelkers.Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, Michigan 48128, United States

Candida albicans is a common, commensal yeast. Over-proliferation, however, can lead to dangerous infections especially in immunocompromised people. Treatments often involve pharmaceuticals that compromise the integrity of the yeast's plasma membrane. We hypothesize that inhibiting phospholipid remodeling in C. albicans will augment the effect of these drugs. Phospholipid remodeling involves the removal of acyl chains and replacement with different acyl species. Initially, we targeted a C. albicans gene homolog to Saccharomyces cerevisiae gene, LPT1, which encodes for a Lysophospholipid acyltransferase. To characterize this homolog (designated 1881), we expressed 1881 in S. Cerevisiae, and performed in-vitro assays to determine the gene's substrate specificity. Our results show that substrate utilization is significantly higher for unsaturated acyl-CoA species than saturated species. We also created homozygous 1881 deletion strains of C. albicans, which are used to perform virulence assays, LysoPL substrate specificity assays and mass spectrometry assays for measuring the rate of phospholipid remodeling.


Why sustainability matters: Creating videos in a water chemistry unit

Joseph R Vincente,, Andrea Swenson, of Science, East Side Community High School, New York, NY 10009, United States

It is our responsibility as educators to help students see their place in the world as active citizens and to expect them to use their scientific knowledge to advocate for sustainable practices. This presentation will focus on a project created by the 10th grade chemistry teacher and school librarian in a public high school in Manhattan in which students created 3-minute Public Service Announcement videos on a water sustainability issue of their choice. Without extensive class time given to video production, students were able to synthesize their understanding of chemistry principles and sustainability and apply their understanding to a social issue. This presentation will describe the process of taking a traditional unit focused on water chemistry and transforming it to culminate in this high-interest, high-quality assessment. Attendees will receive access to easily adapted materials for a variety of educational settings, including an assessment rubric and online examples.


Infusing sustainability into science lessons: Challenges and growth

Resa M Kelly,, Cristina Chang,, Ellen Metzger, Ferdinand Rivera.Chemistry, San Jose State University, San Jose, CA 95192-0101, United States

The overall goal of this Google funded project was to present pre-service teachers (10) enrolled in math and science methods courses with an orientation to climate change/sustainability issues to inspire them to consider relevant ways that they could incorporate sustainability threads in their lessons. The pre-service science teachers were assigned to infuse sustainability into at least one lesson as part of their unit plan, the culminating project of the course. Upon completion, the students presented their sustainability lesson efforts to in-service teachers in the Bay area, SJSU education faculty and graduate students to promote discussion and revision. Examination of their projects revealed weak applications of sustainability and lead to further study to examine in-service teachers' understanding of three components of sustainability as the components were modeled in short You-Tube videos. Results from this study will be shared.


Incorporation of sustainability into chemistry education in Russia

Natalia Pavlovna Tarasova, Chair [quot]Green Chemistry for Sustainable Development[quot], D.Mendeleev University of Chemical Technology of Russia, Moscow, Russian Federation

The first tertiary education organization (Institute of Chemistry and Problems of Sustainable Development) that promotes ideas of sustainable development in Russia is based in the prestigous Mendeleev University of Chemical Technology of Russia and admits students pursuing undergraduate and graduate degrees in areas such as Chemistry, Sociology, Ecology and Environmental Science, and Teaching Chemistry. The goal of the Institute is to promote ideas of interdisciplinary education for sustainable development and to incorporate fundamental science into higher education. Thankfully to continuous efforts over last two decades the subject of Sustainable Development was brought into curriculum of the Mendeleev University.

Several world famous scientists such as Professor Dennis Meadows, Dr. Alan Atkisson and Dr. Bert de Vries visited the Mendeleev University with public lectures (often on multiple occasions). These events encouraged many young students to think broadly about the role of science and especially of Chemistry in the turbulent modern society.


Green Fuels Depot: Demonstrating sustainable energy conversion on a local level

Richard H Jarman, of Health and Sciences, College of DuPage, Glen Ellyn, Illinois 60137, United States

The Green Fuels Depot (GFD) is a collaborative project involving the College of DuPage, the City of Naperville, Argonne National Laboratory and Packer Engineering designed to establish a sustainable energy source based on the gasification of community-generated yard waste. Residential brush and leaf materials will be converted into a flexible system of energy sources, including electricity, hydrogen and ethanol to power municipal transportation. The GFD offers the prospect of a stand-alone sustainable energy source for urban and agricultural communities as well as remote locations that lack grid electricity. The role of the College of DuPage in this project is threefold: to develop training and educational materials for future GFD operators; mentor and train students in the operation of the equipment; perform basic research on the gasification process. A broader objective of this project is to incorporate material into chemistry curriculum to increase awareness of sustainability throughout the student population.


Climate change: What is it? how will it affect us? can we reduce the impact by our actions?

Andy Jorgensen, of Chemistry, University of Toledo, Toledo, OH 43606, United States

Even though climate change has been well characterized over recent years, the physical facts and possible consequences of this phenomenon are not well-known by the public in the United States. The opinions of many in our country have been influenced by climate skeptics who, for various reasons, present an unscientific view of climate change. As a result, there is a desire and interest in further education using peer-reviewed information. A sabbatical leave at the National Council for Science and the Environment during 2008-9 permitted the development of a presentation that has been given more than 50 times in the subsequent three years. The talk utilizes personal response devices to probe the knowledge and opinions of audience members, which allows greater participation by attendees and increases the impact of the message.


Award Address (James Bryant Conant Award in High School Chemistry Teaching sponsored by American Chemical Society). Learning the language of chemistry

Stephen Radice, Teacher, James Bryant Conant Award/Edward R. Murrow High School, Brooklyn, NY 11230, United States

The 2013 James Bryant Conant Award for High School Chemistry Teacher of the year belongs to Stephen Radice.

Presently teaching at Edward R. Murrow High School in Brooklyn, NY, his teaching load has included Chemistry Laboratory for the Hearing Impaired, Advanced Placement Chemistry, Regents Chemistry, Topics in Chemistry, Active Physics, Various Special Education Laboratories including Earth Science and Living Environment. Interestingly, when Stephen is teaching alkanes, he asks students to count from 1-10 in different languages. His point is that students must learn the Language of Chemistry. To challenge and inspire his students, Stephen takes his students to hear lectures by Nobel Laureates; students go to Polytechnic University to do laboratory experiments; or a trip to the Museum of Natural History and the Rose Center for Earth and Space. One of Stephen Radice's former students writes: “He truly personifies both the science of chemistry and the talent of a teacher.”


Teaching chemistry through ice cream

Elizabeth K Mitchell, of Research and Quality, Perry's Ice Cream, Akron, New York 14001, United States

Do you know how much science goes into making ice cream? From freezing point depression to crystallization, there are many ways chemistry impacts making quality frozen dessert products. Learn ways important chemistry concepts can be taught using food science as a basis, because students already understand ice cream!


Electron Cloud Lab: Can the electron really be everywhere at once?

David J. Duncan, OF CHEMISTRY, GANADO UNIFIED SCHOOL DISTRICT, Ganado, AZ 86505, United States

It is difficult for beginning Chemistry students to understand the concept of an electron "cloud", especially when introduced to how small an electron is relative to the size of the atom. Navajo High school students use the scientific method to formulate a hypothesis and test the hypothesis relative to an electron cloud around an atom. By the end of the lesson, the students apply dimensional analysis to set up and solve problems. They use significant figures, scientific notation, conversion factors and a relative size analogy for an atom. They analyze the answers to the calculations to help understand the concepts of radial measurements and that an electron travels in all three dimensions of the electron cloud. The outcome of this exercise was a written lab report.


Green chemistry tools for the high school classroom

Amy Cannon,, Kate Anderson, Benign, Wilmington, MA 01887, United States

Hear about how teachers from across the country are integrating green chemistry into their classroom with lessons and labs that inspire students to connect chemistry concepts to their world. Learn how both food and energy topics can connect to so many chemistry and sustainability concepts.


Inquiry-based lab: Vitamin C clock reaction rate

Anthony McElligott, Academy, New Orleans, LA 70127, United States

Have students discover the basic rules for reaction rates and find evidence to support collision theory on their own. In this lab each group of students can design their own experiment to investigate a different independent variable. The reaction has a clear start and end point and also adds to student investment with the fun color changes that occur.


Food for thought: Safer endothermic and exothermic reactions

Clare Davis Wheeler, Franklin High School, New Orleans, LA 70127, United States

Bring your imagination to the lab bench as you explore new ways for students to learn the same concepts you are already teaching. Explore a green chemistry experiment that demonstrates endothermic and exothermic reactions using an enzyme common to many living organisms and popular candy products.


Polymer food chemistry: Have fun with polymer chemistry by making Mountain DewVair

Sherri Rukes,, Liberyville High School, Libertyville, IL 60048, United States

Ever wonder how some chefs make those exciting little beads for their meals, drinks and creative desserts? It is all about chemsitry. Learn how polymer chemistry and those creative foods are related by learning concepts of various types of crosslinking and other polymer chemistry properties. The session will focus on the making of Mountain DewVair and see how a fun activity such as Gaviscon Snakes, Mountain Dewvair and others connect food science to the basic chemistry classroom. Other topics of polymer food chemistry will also be talked about as extensions. This will get the studetns excited and see how cooking and baking are realated to the chemistry that they learn in the classroom.


Green chemistry alternative energy example: Blackberry solar cell lab

Kate Anderson, Benign, Wilmington, MA 01887, United StatesBeyond Benign, Wilmington, MA 01887, United States

Learn how to construct a dye-sensitized solar cell using materials such as blackberries. During the process students learn about how the materials, product and process meet the cost, safety and performance criteria of green chemistry technology. After construction is complete, performance is tested by measuring the voltage output of the solar cells. Wrap up of the lesson concludes with a discussion about how the technology differs from traditional photovoltaic solar cells and is continuing to emerge.


Impact of teaching metacognitive learning strategies on performance in general chemistry courses

Elzbieta Cook1,, Eugene Kennedy2, Saundra Y McGuire1.  (1) Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States  (2) School of Education, Louisiana State University, Baton Rouge, Louisiana 70803, United States

This presentation discusses details of and outcomes from a 50-minute lecture focused on learning and studying strategies presented to the general chemistry I class after exam 1. For two consecutive years, average final course grades for the attendees of such a lecture were a full letter grade higher than those for the non-attendees. The results of the pre-intervention exam 1 were not significantly different for these two sub-groups, suggesting an absence of significant differences in students' skill levels and motivation prior to exam 1. Detailed course performance and demographic data were collected and analyzed using analysis of covariance (ANCOVA) for the purpose of determining whether participation in the learning strategies lecture had a significant impact on student performance. Other variables considered were: math-ACT scores, high school GPA, hours carried, enrollment year, transfer status, campus housing, gender, ethnicity, and age. Implications for learning strategies instruction in general chemistry are offered.


Implementing a problem-based learning unit on pesticide sensors in general chemistry: Initial outcomes for students and teaching assistants

Megan L Grunert1,2,, Kelley M Current1,2, Lloyd M Mataka2.  (1) Department of Chemistry, Western Michigan University, Kalamazoo, MI 49008, United States  (2) Mallinson Institute for Science Education, Western Michigan University, Kalamazoo, MI 49008, United States

At Western Michigan University, researchers have synthesized molecules capable of detecting the presence of three common pesticides. Through a collaborative effort between research groups, these molecules are being used in first-semester general chemistry laboratory as the foundation for a problem-based learning unit. Students learn about the process of scientific research by designing and carrying out their own experiments using these molecules. Throughout this process, we have been evaluating affective student outcomes through pre/post-surveys, open-response questionnaires, and interviews. We have also been interested in the outcomes for teaching assistants, as they are asked to take on the role of “research advisor” for this unit. Extensive data collection has occurred with the teaching assistants, including classroom observations, classroom audio recordings, recorded weekly meetings, and interviews, allowing us to map changes in teaching practice and the development of an educator identity. Results from the first three implementations will be presented.


Using a grounded approach to develop facet clusters for solutions chemistry

Lianne Schroeder1,, Donald J. Wink2, Stephanie A.C. Ryan1, Matthew Lira1, Susan R. Goldman1, James W. Pellegrino1.  (1) Learning Sciences Research Institute, University of Illinois at Chicago, Chicago, IL 60607, United States  (2) Department of Chemistry, University of Illinois at Chicago, Chicago, IL 60608, United States

Based on a comprehensive review of the K-16 literature, we developed and implemented an interview protocol to explore college chemistry students' understanding of solution phenomena. We were specifically targeting the phenomena of identity (what is in solution), concentration (how much is present, relative to the total amount), and reaction (what happens when new substances are formed). Students were presented with chemical phenomena that elicit qualitative understandings and are asked to describe what they see. Data from these interviews were used to develop three sets of Minstrell-style facet clusters related to solutions phenomena: identity, concentration, and reaction. This approach to facet clusters is unique in that the development is driven by and grounded in student data rather than an expert thought experiment. We will present our method for developing the facets from interview data and an example of the use of the facet clusters to describe a student's understanding.


Transforming the “Survey of Chemistry” class for nursing students using the Learning Assistant (LA) model: Challenges and rewards

Konstantinos Kavallieratos,, Joseph Lichter, Christina A Burns, Lydia Fernandez, Michelle Luzi, Justin M Torner.Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199-0001, United States

The learning assistant (LA) model of instruction has been rapidly expanding due to significant improvement in measured learning objectives. As part of the HHMI-sponsored effort to reform traditional lecture classes at FIU (Grant No: 52006924), we initiated a transformation of the “Survey of Chemistry” class based on LA-directed activities with the following components: 1) Problem solving, aiming at maximizing group interactions and encouraging independent thought 2) Model building and interpreting, linking written structures of molecules to ball-and-stick molecular models 3) Real-life health application problems tailored to nursing students and 4) Problems that seamlessly link the lecture with the lab. Particularly significant features of this transformation are the active involvement of LAs in the problem design and maximized direct LA-student interactions. We will present results on student impacts based on i) direct comparison of exam performance before and after transformation for comparable student groups, and ii) comparison of student outcomes, separated by degree of participation in the LA-directed activities.


Practice-based instructional systems design model for undergraduate chemistry laboratory experiment design

Tara Bunag, of Natural Sciences, Online, University of Phoenix, Tempe, AZ 85040, United States

This presentation will report an iterative model of undergraduate chemistry laboratory experiment design based on the current practice of undergraduate chemistry laboratory design experts (1). The model was constructed using the Delphi method to gather expert responses, then verified through interviews with additional experts. Experts consistently described the model as accurate and useful.

  1. Bunag, T. Construction of an Instructional Design Model for Undergraduate Chemistry Laboratory Design: A Delphi Approach. Ph.D. Dissertation [Online], Arizona State University, Tempe, AZ, 2012.


Structural database for instructors: A living, online NMR FID database

Kyle A Kalstabakken, Andrew M Harned, of Chemistry, University of Minnesota, Minneapolis, MN 55455, United States

Structure elucidation is a fundamental skill for the practicing synthetic chemist. As students become more comfortable with this task, they will become more self sufficient and better able to question the identity of what is in their flask. Because of the importance of this skill, many universities and colleges have established courses on this topic. We have developed a web-based resource to assist instructors of these "organic spectroscopy" courses. This website is populated by NMR FID files that can be freely downloaded by registered users. Current offerings include FID files for 1H and 13C NMR, DEPT, 1H–1H COSY, HMQC, HMBC, TOCSY, and 1D NOE experiments. External users can also submit their own data for use by other instructors. By supplying users with the FID files, it will be easier for them to emphasize certain areas of the spectrum for use during in-class discussions, problem sets, and exams.


Microwave-assisted in-situ cracking of dicyclopentadiene and subsequent reaction with maleic anhydride and the analysis of the Diels-Alder cycloaddition product via 2D-NMR and molecular modeling: A laboratory exercise for an advanced lab course or inter-course collaboration

John G. D'Angelo,, Geoffrey M. Bowers.Division of Chemistry, Alfred Unviersity, Alfred, NY 14802, United States

Herein, we describe the in-situ cracking of dicyclopentadiene with the subsequent reaction of the resulting monomer with maleic anhydride in a Diels-Alder cycloaddition. The Diels-Alder cycloaddition product was then hydrolyzed to the diacid product, consistent with the traditional lab exercise in the undergraduate organic chemistry sequence. The rigid structure of both the anhydride and hydrolyzed diacid make these products ideal candidates for analysis by 2D-NMR and molecular modeling. Such an analysis would be inappropriate for a large class but is ideal in a smaller, advanced lab setting or as a special collaboration project between a small portion of a larger undergraduate organic chemsitry lab and a physical chemistry lab. The findings and complications encountered during our 2D-NMR and molecular modeling analyses will be presented.




Utilizing undergraduate research results in organic spectroscopy

J. Thomas Ippoliti,, Samuel J. Fish, Luke A. Kassekert, Rebecca L. Kummer, Sarah N. Larson, Andrew K. Peterson, Nicholas A. Serratore, Olga Y. Zamulko.Department of Chemistry, University of St. Thomas, St. Paul, MN 55105, United States

A variety of compounds that were synthesized as part of undergraduate research projects have been used as examples to illustrate numerous concepts in an Organic Spectroscopy course. The compounds discussed will illustrate: Karplus curve concepts in cyclohexane rings, fluorine splitting, inverted triplets, anisotropy effects of sterically crowded aromatic rings, how electron donation into aromatic rings can influence proton chemical shifts, the effect of hindered rotation on chemical shift, how intramolecular hydrogen bonding can affect conformational preferences, and vicinal C-H coupling to N-H. An exceptionally interesting molecule showing long range coupling to an O-H as well as demonstrating many other concepts will serve as a multi-faceted example of how these compounds can be used as excellent teaching tools.


Thematic use of ribavirin as an example to illustrate NMR principles and techniques

Brant L. Kedrowski,, William F. Wacholtz.Department of Chemistry, University of Wisconsin Oshkosh, Oshkosh, WI 54901, United States

Ribavirin is a molecule used clinically to treat viral infections. It has a number of structural features that make it an ideal example for illustrating a variety of NMR principles and instrumental techniques. Ribavirin was used in a thematic fashion as a recurring example throughout a semester-long interpretative spectroscopy course to introduce concepts that started with the simple and progressed toward the complex. Examples included: 1) molecular asymmetry and number of signals, 2) diastereotopic methylene proton signals, 3) observing spin-spin splitting between hydroxyl protons and neighboring protons, 4) proton-deuterium exchange experiments with hydroxyl group protons, 5) 1D selective decoupling experiments to assign proton signals, 6) 1D-NOE experiments, 7) temperature-dependent NMR experiments to study amide bond rotation, 8) homonuclear 2-D correlation experiments including COSY and NOESY, 9) heteronuclear 2-D correlation experiments including HETCOR, HMQC, or HSQC for short range C-H correlations, and FLOCK or HMBC for long range C-H correlations.


Quantitative NMR spectroscopy in practical applications for student labs and student research

Donald A Bouchard, Instruments, Inc., Indianapolis, IN 46203, United States

Nuclear magnetic resonance (NMR) is an important diagnostic and research tool in virtually every area of science today. The selectivity of magnetic resonance means NMR is a tremendous tool for qualitative analysis in the determination of molecular structure. A second important property is that NMR is a bulk phenomenon and can measure many samples as is without sample preparation. Finally, the NMR response is uniform per atom, without regard to its structural state and that external calibrations can be very simple, which is particularly useful for a teaching laboratory or student research project. Ignoring the fundamental qualitative aspects of NMR leads students to a myopic view of the power of this technique. The results of projects in real world areas of nutrient content in food, chemical components in crude and finished petroleum and chemical equilibria to be presented can give students an enhanced view of this spectroscopic technique.


NMR spectroscopy at the University of St. Thomas(TX): From general chemistry to undergraduate research

Thomas B Malloy Jr1,, Michelle A Steiger1, Lawrence B Alemany2.  (1) Department of Chemistry, University of St. Thomas, Houston, TX 77006, United States  (2) Department of Chemistry and Shared Equipment Authority, Rice University, Houston, TX 77005, United States

An Anasazi Eft-60 60 MHz multinuclear FTNMR has allowed NMR experiments to be incorporated throughout the undergraduate curriculum at the University of St. Thomas. In addition to the use of NMR in the sophomore organic laboratory course, experiments have been incorporated in inorganic, physical chemistry, biochemistry and instrumental analysis courses. In addition, an effort has been made to involve selected freshmen in NMR projects during their second semester. Undergraduate research has led to the development and refinement of many of the experiments. Access to high field superconducting magnet instruments at the Shared Equipment Authority at Rice University at very reasonable rates has greatly enhanced opportunities for undergraduate research in NMR at the University of St. Thomas.

This presentation will discuss the NMR for freshmen projects, the development of an experiment illustrating the difference in time scales between NMR and Raman spectroscopy, a 2D experiment on peptides, and how 60 MHz results led to ongoing high field studies of unique complex effects in organofluorine compounds.


Writing more competitive grant proposals for NMR spectrometers

Thomas J Wenzel,, Bates College, Lewiston, Maine 04240, United States

It is possible to secure funding for NMR spectrometers through either research grants or curriculum development grants. In particular, the National Science Foundation has two important grant programs that provide support for NMR spectrometers. The Major Research Instrumentation Program operates under the research directorates and is focused on enabling research activities. The Transforming Undergraduate Education in Science, Technology, Engineering and Mathematics Program operates under the Division of Undergraduate Education and is focused on promoting curricular development that enhances undergraduate student learning. Advice for writing successful grant proposals to both of these programs is provided.


Chemistry and chemists within the Division of Undergraduate Education at the NSF

Joseph J. Grabowski,, David R. Brown, Herbert Richtol.Division of Undergraduate Education, National Science Foundation, United States

The Division of Undergraduate Education (DUE) at the National Science Foundation (NSF) offers a number of programs that, in the aggregate, are a comprehensive approach to strengthening STEM education at two- and four-year colleges and universities. DUE programs support improving curricula, instruction, laboratories, infrastructure, assessment, diversity of both students and faculty, and increasingly, collaborations. Chemistry, often considered as the 'central science' in STEM, is a major contributor to advancing DUE's four goals of providing leadership, supporting curriculum development, preparing the workforce, and fostering connections. While DUE can provide the funding, it is the broad Chemistry community that allows the goals to be achieved. In addition to highlighting DUE's interests beyond the solicitations, the role that chemists play in the support of DUE and NSF will be featured.


Using threshold concepts to drive curriculum reform in biochemistry

Vicky Minderhout1,, Jennifer Loertscher1, Jennifer Lewis2, David Green3.  (1) Department of Chemistry, Seattle University, Seattle, WA 98122, United States  (2) Department of Chemistry, University of South Florida, Tampa, FL 33620, United States  (3) Center for Excellence in Teaching and Learning, Seattle University, Seattle, WA 98122, United States

Threshold concepts are concepts that when mastered, represent a transformed understanding of a discipline, without which the learner cannot progress. For example, equilibrium has been identified as a threshold concept in biology and is likely to be relevant for biochemistry. Preliminary data suggest that students bring incomplete knowledge of equilibrium into biochemistry courses and that biochemistry courses do not alter their understanding significantly. By focusing on threshold concepts, instructors can maximize the impact of instruction. We are beginning work with a community of biochemists, biologists and chemists, to 1) identify threshold concepts for biochemistry, 2) design classroom activities targeting these concepts, 3) disseminate classroom activities and assessment tools, 4) measure changes in student understanding. Our prior work linking assessment of student understanding of protein structure to curricular reform provides a model of a process that uses assessment and community input in a feedback loop to improve student learning.


Development of e-learning modules for analytical chemistry

Thomas J Wenzel,, Bates College, Lewiston, Maine 04240, United States

Faculty members from over 20 institutions are collaborating on an NSF-funded project to develop active learning materials for use in the undergraduate analytical chemistry curriculum. Materials are being designed for use in a variety of formats (e.g., classroom activity, homework assignment, laboratory project) and in a form that can be modified to suit the particular needs of an instructor or institution. Each module consists of a series of inquiry-based activities or problem-based exercises. Learning objectives, appropriate textual material and an instructor's manual that support the activity or exercise are provided as well. Materials developed in this project will be disseminated through the NSF-funded Analytical Sciences Digital Library (ASDL), When finished, the classroom activities and laboratory experiences will span the range of topics normally incorporated into the undergraduate analytical chemistry curriculum. Work completed to date, ongoing activities, and future plans for topic development will be described.


IONiC: Transforming education through collaborative development of materials at the frontiers of inorganic chemistry

Sheila R. Smith1,, Sibrina Collins2,, Joanne L. Stewart3,  (1) Department of Natural Sciences, University of Michigan- Dearborn, Dearborn, MI 48128, United States  (2) Department of Chemistry, College of Wooster, Wooster, OH 44691, United States  (3) Department of Chemistry, Hope College, Holland, MI 49422, United States

The Interactive Online Network of Inorganic Chemists (IONiC) was formed to share content and best practices for teaching and learning in inorganic chemistry. Over the past five years, we have built a website and social networking hub, VIPEr (, a home to more than 500 registered faculty users who share teaching resources, advice, and evidence of student learning. An important lesson that we have learned is that in order to get highly engaged participation on the VIPEr site, we need face-to-face contact to invest people in the community. Over the past three years, we have hosted workshops for faculty on content creation and effective use of VIPEr. In this project, we build on our tested workshop strategy and enhance it with a theme we call “Back to Grad School” (B2GS). Specifically, we will host four summer B2GS workshops that will: 1) Introduce faculty to cutting-edge topics in several subfields of inorganic chemistry; 2) develop at least 80 high quality teaching resources in conjunction with research experts; and 3) disseminate these materials to the global inorganic teaching community through VIPEr.


Embedding undergraduate research throughout our campuses and curricula

Mitchell Malachowski1,, Kerry Karukstis2,, Jeffrey Osborn3, Elizabeth Ambos4.  (1) Department of Chemistry, University of San Diego, San Diego, CA 92110, United States  (2) Department of Chemistry, Harvey Mudd College, Claremont, CA 91711, United States  (3) Department of Biology, The College of New Jersey, Ewing, NJ 08628, United States  (4) Council on Undergraduate Research, Washington, DC 20005, United States

This presentation will describe our NSF funded project that focuses on working with state systems and consortia interested in embedding higher levels of undergraduate research across their campuses. We have offered three-day workshops to seven systems/consortia including 90 institutions and over 350 participants. Teams from each institution spend the weekend generating a series of goals for undergraduate research that they bring back to their campuses for vetting. Institutional goals frequently include issues related to faculty workload, resource allocation, facilities, curriculum, student engagement, mentoring, promotion and tenure expectations, summer activities, and grants writing, among others. In this presentation we will discuss the focus of the workshops, the engagement of the faculty and administrators during the weekend, the follow-up activities and the institutional and system/consortia changes that have resulted from the workshops. Issues common to many institutions will be discussed and suggestions made on how to adapt our findings to other institutions.


PhET Interactive Simulations: Using research-based simulations to transform undergraduate chemistry education

Emily B. Moore1,, Julia M. Chamberlain1, Robert Parson2, Katherine K. Perkins1.  (1) Department of Physics, University of Colorado Boulder, Boulder, CO 80305, United States  (2) Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, CO 80305, United States

The PhET Interactive Simulations project ( includes a growing list of over 30 chemistry simulations (sims). Each sim is research-based and student-tested, resulting in sims that support student learning through inquiry – including scientist-like exploration and experimentation. Recent PhET research includes investigations on: sim design – how complexity affects student learning, and the unique needs of chemistry sims; and sim use – how activity design affects student sim use, and how students use and perceive sims in large classes. With new NSF funding, the PhET project will continue to develop sims and study design and use. We will also work with a newly-established chemistry Faculty Working Group towards the development of student and classroom-tested supporting materials (classroom, lab, and homework activities, and clicker questions) and professional development materials.


Chemistry Collaborations, Workshops and Communities of Scholars (cCWCS): Activities and impacts

David M Collard, of Chemistry & Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States

Over the last decade, the Chemistry Collaborations, Workshops and Communities of Scholars program (cCWCS, and its predecessor (the Center for Workshops in the Chemical Sciences) have provided over 120 workshops for faculty. The programs have a long history of equipping faculty to modify courses and curricula through their participation in week-long, hands-on workshops on topics such as chemistry in art, food chemistry, computational chemistry, forensic science, energy, nanotechnology, and NMR. Web-based communities, conference symposia and small grant programs provide continuing support and engagement of the participants. The presentation will focus on the evaluation of the program's impact.


In situ generated palladium nanoparticle assemblies and its electro-catalytic properties towards oxidation of polyalcohols

Caitlyn McCain,, Krisanu Bandyopadhyay.Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI 48128, United States

There is a considerable interest for investigating a general synthesis route to generate aggregation-resistant metal nanoparticles for catalytic applications. The present research deals with the formation of two-dimensional arrays of palladium nanoparticles on functionalized surfaces. Silicon and indium tin oxide (ITO) coated glass are used as preferred substrates and are functionalized with silane molecule like trimethoxysilylpropylpolyethyleneimine. Due to electrostatic interactions between specific functional groups present on the modified surface and metal ions present in solution, adsorption of ions take place on the surface, followed by a reduction step to ensure in situ generation of surface bound nanoparticles. Surface zeta potential measurement is used to follow the change in surface-charge during different steps of the synthetic process Atomic Force Microscopy (AFM) provides the structural characterization of the nanoparticles. Finally, the electro-catalytic activity of these nanoparticles assemblies are assessed for oxidation of polyalcohols like ethylene glycol and glycerol.


Effect of monolayer template on generation of 2D assemblies of gold nanoparticle

Harkamal Jhajj,, Krisanu Bandyopadhyay.Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI 48128, United States

Gold nanoparticles have attracted much interest recently due to their unusual catalytic properties. Our research uses organized assemblies on solid surfaces to generate gold nanoparticles engineered for electro-catalytic application towards methanol electro-oxidation, which is a key reaction for direct methanol fuel cells. In this present research, two dimensional assemblies of gold nanoparticles are generated in situ on silicon and indium tin oxide (ITO) coated glass surfaces functionalized with aminosaline monolayer with different chain length and different number of nitrogen atoms present at the molecular backbone. We have studied the effect of different aminosilane monolayer template on size of generated gold nanoparticle and subsequent assessment as catalyst towards methanol electro-oxidation. Atomic Force Microscopy (AFM), contact angle and surface zeta potential measurements are used to monitor the structural development of these nanoparticles. Further studies are conducted using Impedance spectroscopy to better comprehend the size dependent electrochemical properties of surface generated gold nanoparticles.


Metal oxide nanowire/carbon composites for hybrid supercapacitors

Ruperto G Mariano,, Sanjaya D Perera, Mark Rudolph, Kenneth J Balkus.Department of Chemistry and the Alan G. MacDiarmid NanoTech Institute, The University of Texas at Dallas, Richardson, TX 75080, United States

Much attention has focused on metal oxide nanostructures for use as electrodes in energy storage devices due to their high surface areas and high Li+ion diffusion rates. Nanowire structures are attractive as they can form binder-free electrodes, increasing capacitive performance by eliminating binder materials in electrodes.

Additionally, carbon materials can be used as electrodes in electric double layer capacitors (EDLCs): the use of reduced graphene oxide (rGO) as an electrode material is intriguing due to its high electron mobility and affordability compared to carbon nanotubes (CNTs). The performance of EDLCs can be further enhanced through combination with metal oxides that exhibit redox activity.

In this work, we present a hybrid supercapacitor using MnO2 nanowire/V2O5 nanowire/rGO/CNT electrodes. Characterization performed using SEM/TEM to confirm nanowire morphology, XRD to confirm crystal phases, and Cyclic Voltammetry to determine capacitance and power/energy densities will be presented.


Molecular structure and energy comparisons of graphene-oxide

Erich J Beregszaszy,, Daniel B Lawson.Natural Sciences, University of Michigan-Deaborn, D, MI 48128, United States

Graphene oxide (GO) consists of 2 dimensional sheets constructed from planar and hexagonal CC bonds with oxygen atoms populating the surface. GO is water soluble and is often used to as the starter material for the purposes of depositing graphene onto a variety of surfaces. With ever growing demands in the market-place for green catalysts, the unique electrical and chemical properties of graphite, graphene and graphene oxide offer chemical and electrical properties that suggest a variety of applications in catalytic processes. Unfortunately, the exact chemical structure of GO has yet to be elucidated. This work uses computational chemistry to estimates energetically favorable structures from various models proposed in the literature. The level of oxidation of GO is estimated by the enthalpy of absorption of O atoms to the surface of graphene. We also look into favorability of various other functional groups in GO including –OH, -CO, and –COOH. We compare available experimental data from the literature with our computationally generated results to properly assess the topography of GO.


Interesting luminescent properties of a Suzuki coupled fulgide switch

Kenneth Yamaguchi, Akim Abdullahi,, Usman Shahid.Department of Chemistry, New Jersey City University, Jersey City, New Jersey 07302, United States

The fulgides represent an important class of compounds that have been shown to undergo light-induced ring-opening and -closing states with high photochemical stabilities. We have been interested in the incorporation of this class of photochromic compounds into n- and p-type materials with interesting photochemical properties. This paper will discuss the bromination of 3-methylindole followed by a Stobbe condensation reaction yielded 2-acetyl-3-methyl-6-bromoindole (1). The fulgide switch was synthesized via coupling between the intermediate 1 and diethyl isopropylidene succinate. Finally the fulgide moiety was coupled to 2-bromo-7,7-dioctylfluorene. The synthesis and characterization of the product will be discussed as well as its luminescent properties.


Versatile SERS substrates using period arrays of silver conical nano-frustums

Ryan K Petit,, Jason M Montgomery.Department of Chemistry, Florida Southern College, Lakeland, Florida 33801, United States

Systems involving arrays of periodic metallic nanostructures have been the focus of much interest due to their ability to reliably enhance the intensity of an incident electric field through surface plasmon excitations. These excitations occur at resonant frequencies that are determined by a nanostructure's geometry (size, shape, and environment) and can be therefore tuned to a desired frequency. Accordingly, periodic arrays of metallic nanoparticles can be used for surface enhanced Raman spectroscopy (SERS) applications, in which both the incident light and the Raman scattered light are enhanced. Typically, one aims to tune a surface plasmon resonance midway between the excitation wavelength and the emission wavelength of the analyte in order to adequately enhance both wavelengths, giving rise to the well known g4 enhancement factor. In this paper, we describe a novel structure, composed of a periodic array of layered metallic nano-frustums (NFs) atop a this silver film, intended to support multiple resonance frequencies that correspond to the excitation wavelength (λex), the emission wavelength (λem), and midway between the two (λmid). Two and three dimensional finite-difference time-domain (FDTD) calculations were utilized to analyze possible structures and geometrical parameters and to ultimately optimize a NF structure capable of exciting at both λex = 785nm, λmid = 850nm , and λem = 850nm was designed. The structure exhibited maximum SERS enhancements on the order of 100x higher than previously studied nano-post arrays.


Determination of the structures of imprinted polymers and xerogels: A random docking approach

Amanda Wach,, Jiechen Chen,, Eva Zurek.Department of Chemistry, Stat University fo New York at Buffalo, Buffalo, NY 14261, United States

A method for the computational determination of the binding motifs in molecularly imprintedpolymers and xerogels is proposed. A RandomDock extension to the open source molecular editorAvogadro is employed in order to generate multiple random geometries of the templatesand monomers which are subsequently optimized using dispersion corrected density functional theory.Analysis of the most stable structures obtained shows that they maximize the number ofintramolecular hydrogen bonds in the tetracycline molecule. In addition, hydrogen bonding interactions between thesilane and the TC and ETC molecules are observed. The bonding between the silanes and ATC/EATC, on the other hand, is unspecific and primarily due to dispersion. Systems with tetraethoxysilane as the monomer show the lowest, most favorable binding energy compared to other silanes.




Preparing students for greener workplaces through microwave chemistry

Michael J. Karney,, Grace S. Vanier.Life Sciences Division, CEM Corporation, Matthews, NC 28106, United States

As the industrial and academic chemistry labs of tomorrow evolve, so must the curricula of universities. With the principles of green chemistry presenting both financial and chemical advantages, there has been a focus on improving the efficiency of new and existing industrial reaction pathways according to these principles. With the spread of this new way of thinking about chemistry, microwave reactors have also spread into every discipline of chemistry. Microwave reactors have long been tied to green chemistry because of their efficiency and ability to perform novel reactions. Educating students in the technique and practice of microwave green chemistry prepares them for successful careers, equipping them with advantages both on their resumes and in the laboratory. This presentation will introduce pedagogy and laboratory experiments designed to encourage growth in the realm of teaching microwave green chemistry.


Results and evaluation of a green approach to Knoevenagel–Doebner condensation reaction in a second-year organic chemistry laboratory class

Koushik Banerjee, Ruchi Patel,, Peng Hao.Department of Chemistry, Physics and Astronomy, Georgia College and State University, Milledgeville, GA 31061, United States

As part of our efforts to minimize the use of toxic chemicals in organic chemistry instructional laboratories, a newly developed Knoevenagel–Doebner reaction in a multistep sequence to 2'-bromostyrene was developed and applied over a period of four semesters. The conventional base used during this reaction used to be pyridine, which is a highly toxic compound. We have been able to replace pyridine with a nucleophilic catalyst, DMAP, as well as discover and apply a microwave-mediated route. Herein, we will present the results and evaluations of this green reaction in second-year organic chemistry laboratory carried out during the past year.


Sustainable polymers in the organic chemistry laboratory: Synthesis and characterization of a fully renewable, degradable polymer from δ-decalactone and L-lactide

Jane E. Wissinger1,, Debbie Schneiderman1, Marc Hillmyer1, Tomohiro Kubo1, Michael Wentzel2, Chad Gilmer2.  (1) Chemistry, University of Minnesota, Minneapolis, MN 55455, United States  (2) Chemistry, Augsburg College, Minneapolis, MN 55454, United States

The importance of green and sustainable polymers is highlighted in a new experiment developed for incorporation into the organic chemistry laboratory curriculum. δ-Decalactone, a naturally occurring cyclic ester used by the food and flavor industry for its coconut fragrance and taste, was polymerized by ring opening transesterification polymerization (ROTEP) under acidic conditions with a diol initiator. The synthesis is notable for its solvent free, room temperature reaction conditions as well as the ease at which the catalyst can be removed from the polymer. 1H NMR analysis of the resulting viscous product was used to determine the monomer conversion obtained and calculate the molecular weight of the telechelic poly(δ-decalactone) formed. Continuation of the experiment involved chain extension with L-lactide to yield a flocculent copolymer material. Subsequent annealing resulted in a transparent, pliable, polymer film. The well resolved 1H NMR peaks of the two component monomers facilitate a quantitative analysis of polymer composition. The use of 100% renewable feedstocks and green reaction conditions to produce an environmentally friendly polymer with interesting properties exemplifies modern advances in sustainable polymer chemistry in the classroom.


Green Chemistry Commitment: Transforming chemistry education

Amy S Cannon1,, John C Warner2, Kate Anderson1.  (1) Beyond Benign, Wilmington, MA 01887, United States  (2) Warner Babcock Institute for Green Chemistry, Wilmington, MA 01887, United States

This presentation will describe the history and progress for a new program titled the Green Chemistry Commitment. The program is a departmental commitment designed for higher educational institutions as a voluntary, flexible framework for chemistry departments to adopt green chemistry theory and practice. The Commitment is centered on student learning objectives that take into account topics such as green chemistry and toxicology, which have traditionally been absent from chemistry programs. College and university chemistry departments sign on to the Commitment, indicating that they value the student learning objectives and committing to working towards implementing the student learning objectives within their own departments. The Commitment is designed so that each institution can adopt the student learning objectives through different means, recognizing that each department will have different resources and different capabilities.


Green organic chemistry at Kingsborough Community College

Homar S Barcena,, Pei Shan Chen.Physical Sciences, Kingsborough Community College, Brooklyn, NY 11235, United States

Green experiments were adapted for the Organic Chemistry I and II curricula at a community college setting. A new laboratory book was prepared for both courses. Students were introduced to principles of green chemistry, green metrics, safety, and hazards assessments. Where possible, contextual references to the environment and human health were linked to the labs. Students were evaluated from pre-labs, post-labs, and keeping laboratory notebook. These pedagogies show that green chemistry effectively engages student interest and appreciation of the subject matter, and that green Organic curricula can be effectively implemented at community colleges.


Teaching green chemistry in the developing world

Roseann K. Sachs1,2,, Seng Samphors1.  (1) Department of Chemistry, Royal University of Phnom Penh, Phnom Penh, Cambodia  (2) Department of Chemistry and Biochemistry, Messiah College, Mechanicsburg, PA 17055, United States

During the 2009-2010 academic year, a new laboratory course in Green Chemistry was developed at the Royal University of Phnom Penh, in Phnom Penh, Cambodia. This university is the oldest public institution of learning in Cambodia, but is still recovering from the losses incurred during the Khmer Rouge and subsequent years of civil war. In this new course, students were asked to think critically, work in groups, but sometimes independently, analyze their data and prepare laboratory reports, all while learning ways to do chemistry in a more sustainable way. Designed for third year university students, this course included six experiments, one of which was research focused and challenged the students in significant ways, being previously unexposed to laboratories of this type. A number of group exercises were developed and used to encourage critical thinking about the experiments, analysis of chemical risk, and green chemistry, all within the Cambodian context.


Undergraduate research and the Green Chemistry Commitment: Training students to serve society as scientists and professionals

Edward J. Brush, of Chemical Sciences, Bridgewater State University, Bridgewater, MA 02325, United States

One of the learning objectives of the Green Chemistry Commitment states that chemistry majors should be able to “serve society in their professional capacity as scientists and professionals through the articulation, evaluation and employment of methods and chemicals that are benign for human health and the environment.” This goal can be accomplished through incorporating green chemistry principles into undergraduate research projects. The benefits of undergraduate research have been well documented, but when combined with green chemistry principles an unusually strong synergy was created. Our green chemistry research group begins their research experience as part of our freshman summer bridge program. Group activities include study and application of the 12 Principles of Green Chemistry, research and general discussion meetings, and semester and summer grants that are driven by student proposals. Besides training in basic chemistry research, we have observed the evolution of a student culture centered on green chemistry and sustainability.


Chemistry of Cajun cooking competition

Justin S. Miller1,, Gavin L. Sacks2,  (1) Department of Chemistry, Hobart and William Smith Colleges, Geneva, NY 14456, United States  (2) Department of Food Science, Cornell University - NYSAES, Geneva, NY 14456, United States

Finalist teams from the “Communicating Chemistry: Cajun Cooking” (C4) competition will present their take on the chemistry of Cajun cuisine. The entries will relate to the regional cuisine of New Orleans, interpreted broadly. Entries may focus on a well-known Cajun dish; a technique important to regional cooking; or on chemical transformation that unites the cuisine.


Chemist + Chef = Recipe for culinary chemistry delight

Holly Sebahar,, Bryan Woolley.Department of Chemistry, University of Utah, Salt Lake City, UT 84112, United States

Culinary Chemistry at the University of Utah is designed to demonstrate the beauty, relative simplicity, and relevance of science to an aspect of everyday life that everyone loves and appreciates. The ultimate desired outcomes of this course are to convince students that science can be fun and thought-provoking without being analytically complex, to stimulate students' interest in science as it relates to food and cooking, to educate students about nutrition and the health consequences arising from what we eat, and to encourage students to become more conscientious consumers. The course is team taught by a professional Chef and an Organic Chemist. The majority of class periods are held at a professional kitchen where the students perform a great deal of cooking themselves. This team taught approach adds much complexity and flavor to the course. The students learn traditional concepts such as acid/base chemistry, intermolecular attractions, and physical properties. They are also exposed to the history of food, specialized cooking techniques, and professional equipment such as steam ovens and induction cooktops. Examples of the recipes, course assignments, and student feedback are described.


Chemistry in the public eye: Social media, active displays, and immediate open access

Jeffrey J Bodwin, of Chemistry, Minnesota State University Moorhead, Moorhead, Minnesota 56563, United States

Chemistry is a fascinating and fun science that all too often is sequestered behind closed doors in labs that have a mysterious, complex & intimidating aura. As educators, we often try to make chemistry more accessible in the classroom, but often students already have a negative view of chemistry before they ever attend their first class. The open-science movement has developed in part to address some of these problems and has been greatly aided by social media and other publicly accessible (both physically and intellectually) venues. Various social media strategies and other web-based outreach/open-science activities will be presented, as well as preliminary assessment of their effectiveness.


Undergraduate teaching laboratory exercise for the analysis of caffeine and benzoate in beverages

Corina E Brown1,, Peter Karnilaw2, Richard M Hyslop3.  (1) Chemistry and Biochemistry, University of Northern Colorado, Greeley, CO 80639, United States  (2) Chemistry and Biochemistry, University of Northern Colorado, Greeley, CO 80639, United States  (3) Chemistry and Biochemistry, University of Northern Colorado, Greeley, CO 80639, United States

An HPLC method for the analysis of caffeine and benzoate in beverages was developed for use in an undergraduate teaching laboratory. The method involves the simultaneous preparation of caffeine and benzoate standards as well as simultaneous analysis of the two analytes. Separation is accomplished using a C-18 column with an isocratic mobile phase of methanol:acetate buffer using UV detection. Quantification is linear over the range of 50-250 ppm for caffeine and 100-500 ppm for benzoate. Beverages containing either caffeine, benzoate, or both are degassed if carbonated with dilution with appropriate dilution prior to analysis. Standard preparation, sample preparation, and analysis of both can be accomplished within a typical three-hour laboratory period.


What's wrong with a diet root beer float? Freezing point depression studies with beverage sweeteners

Roderick S Black,, Andrew D Spaeth, Lianna Dang, Dustin Moseley.Department of Chemistry, University of Kansas, Lawrence, KS 66045, United States

The smooth texture of a multi-phase treat like the “ice cream soda” can be disrupted by ice crystals near its solid/liquid interface. Thus, the freezing point of a beverage can be important for successful pairing with a frozen dessert, especially for low-solute-molality diet beverages, which freeze at higher temperatures than their conventionally sweetened counterparts. In an undergraduate Chemistry Club activity outside of the conventional science laboratory, students make ice cream sodas and use their scientific knowledge to illuminate texture and flavor critiques of diet and conventionally-sweetened desserts. In a related general chemistry exercise, students study the significance of colligative properties in multi-phase dessert design by determining the freezing points of sucrose and artificial sweetener solutions. Advanced experiments assess the average molar masses of mixed-sweetener products. Student enthusiasm for the study of colligative properties is fostered by examining the impact of concentration on selection of appropriate beverages for chilled desserts.


Teaching chemistry at a technical college through practical field work: Milwaukee River project

Scott A. Schlipp,, Janice L. McCann, Dinah Nelson, Chris Emcke.Department of Natural Science, Milwaukee Area Technical College, Milwaukee, WI 53215, United States

Milwaukee Area Technical College (MATC) chemical technician students collect river water samples from five predetermined sites along the Milwaukee River that encompass Milwaukee County's watershed. MATC students conduct field analysis at these river sites to collect data for phosphorus, pH, dissolved oxygen, nitrates, nitrites, flow rate, temperature, and the use of solid phase microextraction (SPME) for the detection of pesticides through gas chromatography mass spectrometry (GC/MS). The river samples are also analyzed for heavy metals by inductively coupled plasma (ICP), nitrates and nitrites by ion chromatography (IC) and visible spectroscopy for phosphorus by the ascorbic acid method. All field and laboratory analysis is performed by the MATC chemical technician students at MATC. This project is designed to teach two-year students the methodology of a research project through a hands on approach. MATC students learn to analyze the results and prepare their findings for a presentation in a poster format.


Characterization map of scientific text: A tool designed to improve chemistry students' scientific writing

Salete L Queiroz1,, Jane R. S. Oliveira2.  (1) Institute of Chemistry, University of São Paulo, São Carlos, São Paulo 13561-200, Brazil  (2) Department of Chemistry, Federal University of São Paulo, São Carlos, São Paulo 13565-905, Brazil

Despite substantial evidence that writing can be an effective tool to promote student learning and engagement, writing-to-learn practices are still not widely implemented in chemistry disciplines in Brazil, particularly at research universities. To address these issues, we undertook an initiative to design a tool to improve undergraduate chemistry students' scientific writing: Characterization Map of Scientific Text. The Characterization Map is mainly based on Bruno Latour's Science in Action (Latour, 1987). The Map has structural and rhetorical aspects of the scientific writing, as well as textual elements related to these aspects.

In addition we applied this tool in inorganic and organic chemistry disciplines offered to undergraduate students in Brazilian universities. The main objective of this paper is to investigate its functioning as a facilitator in improving scientific writing of the students and as a scientific texts analysis tool.

Latour, B (1987). Science in action: how to follow scientists and engineers through society. Cambridge: Harvard University Press.


Measuring student understanding of acid-base reactions using the Acid-Base Concept Inventory (ABCI)

Jana Jensen,, Stacey Lowery Bretz.Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States

The purpose of this study is to identify misconceptions that students have about acid-base reactions. Our research questions include: (1) How do students identify acid-base reactions? (2) What features stand out to students as essential in acid-base reactions? Thirty-four students were interviewed from high school, general chemistry 1 & II, organic chemistry I & II, and a graduate level organic chemistry seminar regarding their classification schemes for 13 reactions. A 28-item Acid-Base Concept Inventory (ABCI) was developed using student interviews. The distracters within the inventory come directly from student explanations of how particles interact in reactions. The ABC Inventory was pilot tested with 1,199 students in high school, general chemistry, and organic chemistry courses. Results from a final study with a national sample of general chemistry students will be presented.


Using advanced statistical analyses in chemical education research: Applications of structural equation modeling, cluster analysis, and multinomial logistic regression

Jeffrey R Raker1,, Kimberly J Linenberger1,, Kristen Murphy2, Thomas A Holme1.  (1) Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States  (2) Department of Chemistry & Biochemistry, University of Wisconsin - Milwaukee, Milwaukee, Wisconsin 53201, United States

Advanced statistical analyses including structural equation modeling, cluster analysis, and multinomial logistic regression provide education researchers with additional methods for testing hypotheses about binary, ordinal, and continuous data. This poster will present results from three studies conducted by the ACS Examinations Institute. 1.) The use of structural equation modeling to gage the impact of objective and subjective exam item complexity on student performance. 2.) The use of cluster analysis to identify levels of chemistry faculty familiarity with assessment terminology. 3.) The use of logistic regression to understand the differences on several assessment instruments between students enrolled in several different general chemistry courses. We will present a brief background, the types of questions that can be answered, and how to interpret the results for each method.


Developing an instrument to measure meaningful learning in the undergraduate chemistry laboratory

Kelli R Galloway1,, Taylor Owings2, Marcy Towns2, Stacey Lowery Bretz1.  (1) Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States  (2) Department of Chemistry, Purdue University, West Lafayette, IN 47907, United States

While there exists a large literature discussing the importance the undergraduate teaching laboratory, there is remarkably little data on its impact, including student perspectives regarding their laboratory experiences. Student perspectives need to be understood in order for teaching and learning in the undergraduate laboratory to improve. Novak's Theory of Meaningful Learning states that the cognitive, affective, and psychomotor domains must be integrated for meaningful learning to occur. Therefore, for students to learn meaningfully in the laboratory, they must not only be cognizant of each domain, but also achieve integration of three domains. In order to investigate students' meaningful learning in the laboratory, an instrument was developed to measure student expectations and experiences with regard to performing laboratory experiments. The items for the survey were inspired by existing instruments including the CSCI, ASCI, ASCIV2, CHEMX, MCAI, CLAI, C-LASS, and CASPiE lab scales due to their direct incorporation of one or more meaningful learning domain(s). The Meaningful Learning in the Lab Inventory has been pilot tested with general, organic, and physical chemistry students at both a large Midwestern research university and a moderate size Midwestern liberal arts university. Results from the pilot testing will be presented.


Education abroad in the sciences: Dickinson College's Norwich Science Program

R. David Crouch1,, Brian Brubaker2.  (1) Department of Chemistry, Dickinson College, Carlisle, PA 17013, United States  (2) Center for Global Study and Engagement, Dickinson College, Carlisle, PA 17013, United States

Although participation in education abroad programs by U.S. undergraduates has doubled in the past ten years, students majoring in the sciences continue to participate in much smaller numbers than their peers in the arts & humanities, foreign languages and social sciences. At Dickinson College in the 1990s, science majors rarely went abroad despite a high overall level of participation in the college's robust portfolio of programs. The College sought to increase education abroad opportunities for science majors through the creation of a program that specifically met the needs of these students, allowing them to progress in large, hierarchical majors at the host university. This poster describes the current program for science students -including those majoring in chemistry and biochemistry - that Dickinson offers at the University of East Anglia in Norwich, United Kingdom.


Active reading documents (ARD's) as a tool to promote student learning through meaningful reading of class material

Santiago A Toledo, of Chemistry, Texas Lutheran University, Seguin, TX 78155, United States

A common struggle for educators of chemistry is to be able to promote student interaction with the textbook and other class material prior to coming to class. This work discusses the use of Active Reading Documents (ARD's) as a tool to promote and build accountability around the students' need to engage actively with the reading before class. The ARD's goal is to help students develop basic understanding, at different cognitive levels, of the material before they first encounter it. This allows the instructor-student time to be spent not lecturing over the book content, but facilitating and promoting higher level learning. A detailed rubric for grading the ARD's will be discussed and student generated examples will be shared. In addition, a brief description will be provided of Marzano's Taxonomy which is the theoretical framework from which the learning objectives for this student activity are derived.


Integrating current scientific research topics and literature into analytical chemistry courses at a primarily undergraduate institution

Niina J Ronkainen, of Chemistry and Biochemistry, Benedictine University, Lisle, IL 60532-0900, United States

Teaching chemical concepts and process skills in a context that is relevant to students' lives is an effective pedagogical approach. It is important that undergraduate students become exposed to the critical analysis and interpretation of scientific data before entering graduate or professional programs. The incorporation of scientific research literature and topics into three Analytical Chemistry courses at a Primarily Undergraduate Institution will be described. The pedagogical approach, course content, learning objectives, and testing using context based questions will be explained.


Periodic pyramid of the elements

William Tandy Grubbs,, Jennifer N Hennigan.Department of Chemistry, Stetson University, DeLand, FL 32723, United States

The maximum number of electrons that can occupy the successive electronic shells of the atom, given by 2, 8, 18, and 32 for the first four shells, are shown in this work to be related to the triangular numbers from mathematical number theory. This geometric relationship suggests an alternate method for arranging elements in terms of periodicity. The resulting three-dimensional 'periodic pyramid' is highly symmetric in shape, and the overall structure of the pyramid can be separated into shell and sub-shell contributions. Examining the pyramid's structure is arguably a pedagogically useful classroom activity, as it gives students an opportunity to further ponder periodicity and to grapple with the shell model of the atom.


Comparison of student learning retention using audience response devices

Jeffrey A Jenson,, Hafed A Bascal.Department of Physical Science, The University of Findlay, Findlay, United States

For some time now, audience response devices (clickers) have been used in a classroom setting. In my classes, clickers have been used for the administration of in class quizzes for a number of years. Students enjoy this form of quiz rather than the old paper quizzes primarily because of the instant feedback they get. Clickers can also be quickly graded and uploaded to the learning management system, making my job easier.

One aspect of learning that needs to be addressed is retention of information from the time it is presented in class to the time of the final examination. Many students memorize information for exams and then quickly forget the information. Methods have been developed to discourage memorizing but have they worked?

This poster will provide data on retention of the same questions asked on the ACS final examination. The students will not be told any details of the ACS exam to keep its integrity intact. In this way student retention of information can be obtained.


Building bridges: Integrating mathematics, science, and engineering on the South Plains

Laci Singer,, Erin Oliver,, Dominick J. Casadonte.Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, United States

“Building Bridges” is Texas Tech University's National Science Foundation GK-12 program, focusing on the integration of mathematics, science, and engineering in graduate research and in the K-12 environment. This is accomplished by creating STEM Cohorts, where STEM Graduate Fellows pair with math or science Teacher Fellows at the same school. The organization of the program at TTU is designed to 1) facilitate the research activities of the Graduate Fellows, 2) develop professional experiences for both Graduate and Teacher Fellows, 3) encourage collaborative design and implementation of an integrated curriculum, and 4) create cyber-capable dissemination platforms for nationwide outreach through a distance-learning classroom environment. Through their experience in the “Building Bridges” GK-12 program, the STEM Graduate Fellows, Teacher Fellows, and K-12 students gain an enhanced understanding of the interconnectedness of STEM disciplines in research and academia. The model developed is one that can be easily replicated to further interdisciplinary STEM education.


Science of art: From creation to authentication to preservation

Kassy A Mies,, Sayyeda Zeenat A. Razvi.Department of Chemistry, Physics, and Geoscience, Meredith College, Raleigh, North Carolina 27607, United States

The Chemistry Program at Meredith College has developed a new travel course, “ The Science of Art: from Creation to Authentication to Preservation.” This course was taught as a part of the College's Study Abroad Program in Sansepolcro, Italy during the summer of 2012. This five week course fulfilled the natural science elective for non-science majors for the general education curriculum and was developed by a chemistry faculty member and a senior chemistry major. The goal of this course was to apply basic scientific theories to understand the creation, authentication, and preservation of art using Italy as classroom. We used a combination of in-class lectures, hands-on activities, debates, field trips, and student presentations to demonstrate the interwoven nature of art and chemistry. Here we will focus on the course modules used to connect Italian art to fundamental chemical principles: Basic Chemistry; Atoms and Light; Compounds; and Solvents, Solutions, and Solubility.

CHED 100

Development of a photographic gallery of crystallization techniques and the errors associated with them

J. Martin E. Quirke1,, Jonathan C. Quirke2, Mayra Exposito1, Lilia San Miguel1.  (1) Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States  (2) Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44704, United States

Laboratory textbooks and manuals contain very few high quality photographs, if any, to reinforce the narrative. Also, they do not show what happens when students fail to follow their instructions on techniques. Thus, students may not understand the need to follow instructions. This photographic presentation surveys a range of techniques including single solvent, mixed solvent and vapor phase diffusion crystallizations, together with the errors associated with them. Fundamental methods are demonstrated by crystallizations using Pd (II) octaethylporphyrin, Zn(II) octaethylporphyin, acetamide and 1,2,3,4-tetraphenylnapthalene. Samples were chosen to illustrate different facets of the techniques and phenomena such as the generation of different crystal forms. Common errors including incorrect solvent selection, misuse of decolorizing charcoal, improper hot filtration are shown. In addition to reinforcing the need to follow experimental technique, the galleries are useful in assisting students to diagnose the cause of any mistakes that they have made.

CHED 101

Student goals for undergraduate laboratory

Marcy H Towns2,, Taylor Owings2, Stacey Lowery Bretz1, Kelli Rush Galloway1.  (1) Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States  (2) Department of Chemistry, Purdue University, West Lafayette, IN 47907, United States

Reviews of laboratory research have suggested the need for further articulation of faculty goals for laboratory. Along side of that research lies the need to understand student goals for laboratory and the interaction between the goals of faculty and students. We have recently embarked upon project designed to elucidate and probe the student goals for undergraduate chemistry laboratory. Students in general chemistry, organic chemistry, and physical chemistry laboratory courses were surveyed at the beginning and end of the semester about their goals and how they expected to achieve them. Results from this study will be shared.

CHED 102

Council on Undergraduate Research: A faculty development organization

Robert E. Bachman, of Chemistry, Council on Undergraduate Research, Washington, DC 20005, United StatesDepartment of Chemistry, The University of the South, Sewanee, TN 37383, United States

Collaborative student-faculty research, scholarship and creative activities, commonly referred to as undergraduate research, has been increasingly recognized as a high impact educational practice in numerous studies of effective pedagogies. The Council on Undergraduate Research (CUR) is the leading national voice of faculty engaged in research with undergraduates. This presentation will highlight CUR's structure and the many services CUR offers to faculty currently working with undergraduate students in research, or interested in beginning such work.

CHED 103

NSF S-STEM scholarship and support mechanisms: A cohort-based summer bridge program in chemistry

Kate J Graham, Edward J McIntee,, Paige M Armbrister.Department of Chemistry, College of Saint Benedict/Saint John's University, Saint Joseph, MN 56374, United States

The College of Saint Benedict/Saint John's University (CSB-SJU) was awarded an NSF S-STEM grant in August 2011. The primary goal of the FoCuS Scholarship and Support Program is to increase the number of students, particularly high achieving students from groups historically underrepresented in science completing a major in chemistry or biochemistry at CSB-SJU. FoCuS provides scholarships and an infrastructure to support our FoCuS students (and all of our majors) throughout their college careers. These efforts will improve our retention of the FoCuS scholars. We have planned a support system for these students utilizing several key activities. This presentation will focus on cohort-building activities during our summer bridge program that have proven to be crucial for the retention of FoCuS students.

CHED 104

Chemistry self-concept, chemistry achievement, and instructional methods in high school chemistry classrooms

Sara E Nielsen,, Ellen J Yezierski.Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States

Student beliefs, though less often studied than achievement, are an important part of students' success in chemistry. Prior research has shown that students' beliefs about their ability to do chemistry affect their performance and persistence in chemistry. Albert Bandura's Social Learning Theory considers a reciprocal relationship among three determinants that affect students: personal, behavioral, and environmental. In this study the personal determinant is represented by student self-concept, the behavioral determinant is represented by student achievement, and the environmental determinant is represented by the instruction students receive. The determinants are measured with the Chemistry Self-Concept Inventory, content quizzes, and the Reformed Teaching Observation Protocol, respectively. To investigate the nature of the relationships among the three determinants, a longitudinal study is being conducted with high school chemistry students. An analysis of several rounds of self-concept, achievement, and instructional methods data will be presented.

CHED 105

POGIL activities that use climate change to teach general chemistry

Daniel King1,, Jennifer E Lewis2, Karen Anderson3, Douglas Latch4, Susan Sutheimer5, Gail Webster6, Cathy Middlecamp7, Richard Moog8.  (1) Department of Chemistry, Drexel University, Philadelphia, PA 19104, United States  (2) University of South Florida, United States  (3) Madison College, United States  (4) Seattle University, United States  (5) Green Mountain College, United States  (6) Guilford College, United States  (7) University of Wisconsin, Madison, United States  (8) Franklin and Marshall College, United States

Climate change is a topic that is familiar to most students. It is also a topic that relates to many topics covered in general chemistry. Through an NSF-funded project, we are developing a series of in-class POGIL (Process Oriented Guided Inquiry Learning) activities that use climate change topics to teach general chemistry concepts. It is expected that these new activities will help engage students in learning fundamental general chemistry concepts. We will also be investigating student discourse collected during the activities. This information will inform revisions of the activities so that they better promote both the development of scientific concepts and how these relate to socio-economic and environmental issues. A set of activities have been written and are being tested during the 2012-2013 academic year. The key features of the activities and feedback on their use will be described in this presentation.

CHED 106

History of chemistry capstone course: New solutions to an old problem

Alan J Rodríguez,, Ingrid Montes.Department of Chemistry, University of Puerto Rico, Rio Piedras, Puerto Rico 00976, Puerto Rico

Courses on the History of Chemistry have been, in the past, the source of heated debate in terms of their profit and relevance to the chemistry curriculum. Based on the number of publications on the topic, the teaching of these courses reached its peak almost 40 years ago and has been decaying ever since. Nonetheless, in the last few years, a couple of papers have been published on the topic, hinting to a renewed interest on the discipline. To attend this, a capstone course has been designed that integrates both graduates and higher-level undergraduate students in a non-traditional experience that fosters creativity, problem solving skills, general knowledge, and teamwork. The course has been implemented and found out to successfully attend the shortcomings of the traditional design. The preliminary results are very promising. The design, methodology and preliminary findings will be detailed.

CHED 107

Increasing student retention in chemistry and other STEM majors through the Collaborative Learning Program

Mandy M. Raab1,, Matthew A. Fisher2, Stephen M. Jodis1.  (1) Herbert W. Boyer School of Natural Sciences, Mathematics, and Computing, Saint Vincent College, Latrobe, PA 15650, United States  (2) Department of Chemistry, Saint Vincent College, Latrobe, PA 15650, United States

The Collaborative Learning Program (CLP) at Saint Vincent College focuses on the problems faced by many undergraduate institutions in capturing and maintaining a student's enthusiasm for a chosen STEM discipline long enough to reach graduation. CLP is designed to increase student mastery of course concepts and persistence in majors such as chemistry and biochemistry through the use of collaborative learning environments held outside of class and led by student facilitators. Discussions include real-world applications to course concepts. In its fourth year, the program has successfully reached important benchmarks related to student participation in CLP sessions and retention in STEM majors. We will present an overview of the CLP program and data related to program impact, including a comparison of course pass rates for General and Organic Chemistry with prior historical data.

CHED 108

Impact on facilitators of involvement in Saint Vincent College's Collaborative Learning Program

Bettie A. Davis1,, Mandy M. Raab2, Matthew A. Fisher1.  (1) Department of Chemistry, Saint Vincent College, Latrobe, PA 15650, United States  (2) Herbert W. Boyer School of Natural Sciences, Mathematics, and Computing, Saint Vincent College, Latrobe, PA 15650, United States

The Collaborative Learning Program (CLP) at Saint Vincent uses outside of class collaborative learning sessions led by student facilitators to increase student mastery of concepts in science courses such as general chemistry and general biology. Student facilitators are responsible not only for leading the sessions but also planning and developing the activities used. While a number of studies have looked at the effectiveness of peer-led sessions for students taking general or organic chemistry, much less attention has been given to the impact of serving as a facilitator on a student's knowledge and understanding of the material, ability to communicate this knowledge, and goals for future pursuits. This poster will present initial results of interviews conducted with past and present facilitators that focus on these questions.

CHED 109

Predictors of student success in general chemistry courses

Sarah J. Pilkenton1,, Catherine F. Dignam1,, LaDonna Bridges2, Michelle Sterk Barrett2.  (1) Department of Chemistry and Food Science, Framingham State University, Framingham, MA 01701, United States  (2) Center for Academic Support and Advising, Framingham State University, Framingham, MA 01701, United States

Enrollment in first year chemistry courses for science and engineering majors have experienced a marked growth at Framingham State University. Enrollment increases have led to University wide discussions regarding student success in all STEM gateway courses. It is desired that the number of students who withdraw from the course or who earn grades of D or F be reduced without compromising the quality of the education provided. In an effort to better understand what types of qualities a successful first-year chemistry student exhibits, a study has been undertaken to identify predictors of student success in general chemistry courses based on student SAT mathematics and reading scores and student performance on math placement exams. A significant correlation between student scores on the mathematics and reading scores on the SAT and the Accuplacer mathematics exam and student success in freshman chemistry courses has been observed. It is the hope that this information will be used in two ways (1) to better inform advising and prerequisite policies and (2) to develop appropriate support and preparative programs geared toward students who have predictors that correlate with a high probability for unsuccessful completion of general chemistry.

CHED 110

Hands-on STEM education and enchanted experiences for students with blindness or low vision (BLV)

Roger Tower, Science, West Lafayette, Indiana 47906, United States

Commonly relegated to note taker or secretary, a student with BLV often is not given the hands-on learning opportunities provided for their peers. Roger Tower presents his experiences from the Enchanted Hills Summer Camp (EHC) for the Blind and the importance of inclusion of students with disabilities in science courses. In partnership with the San Francisco Lighthouse for the Blind, EHC empowers individuals to find strength, confidence and independence while enjoying nature, making friends, and meeting other people with disabilities. Set deep in the hills of Napa Valley, campers conducted experiments in their local environment with the accessible data collection tool, Talking LabQuest. Explored are the values of an educational summer camp experience for all students' growth and interest in academic material. Learn how accessible science, technology, engineering, and mathematics (STEM) can be, with the right tools and methodologies.

CHED 111

Multi-Sensory Science Teacher Education Research Laboratory (the MISTER Lab) at Illinois State University

Cary A Supalo,, Illinois State University, Normal, IL 61790, United States

This research laboratory has been founded on the premise that multi-sensory science approaches to teaching enhances student learning. This entity is committed to student engagement and the full integration of all students including those with special needs. This research laboratory focuses on the acquisition and testing of hands-on learning tools in all areas of science. Further, the uses of virtual laboratory modules along with haptics interfaces are areas of interest. Through the multi-sensory inputs and outputs of scientific concepts, it is believed this will make science more inclusive for all learners. The MISTER Lab is committed to universal design approaches to teaching science and we are interested in collaborations with other researchers who are equally committed. The use of text-to-speech interfaces for students with blindness or low vision (BLV) is another primary area of interest. We believe hands-on tactile and audio outputs complements and reinforces science learning for all students.

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Design and implementation of general chemistry curriculum for pre-service teachers

Pong Kau Yuen1,, Diana, Cheng Man Lau2.  (1) Faculty of Science and Technology, University of Macau, Macau  (2) Faculty of Management and Administration, Macau University of Science and Technology, Macau

Chemistry is an important science subject and the effectiveness of chemical education is critical to the advancement of scientific literacy of students. Chemical education is the central part of the science education. In order to fulfill the requirements for the minor program in science education, the general chemistry curriculum have been designed and implemented for the Macau's pre-service teachers. The purpose of this paper is to review the mechanism of designing chemistry curriculum and introduce the objectives, the content, the teaching approach and the assessment of the chemistry courses for the pre-service teachers in Macau.

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Influence of student-created technique videos on long-term retention of student technique

Mitzy A Erdmann,, Joe L March.Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL 35205, United States

Video capable cellular phones have become increasingly important in documenting everyday life events. This trend presents educators with an exciting opportunity to extend this capability into the introductory laboratory. Having already shown the feasibility of having students create technique videos with previously owned hand-held devices, the authors focused on gains in student technique following completion of the video assignment. Short-term gains of student technique using (1) an analytical balance and (2) a Mohr pipet have been previously reported. Long-term retentions was determined and compared to previously collected short-term retention findings. An experimental group created a pipet video while a control group created a balance video. Gains in students' ability to record volumes using the correct significant figures or minimize error when using an analytical balance were compared to pre-activity and at the end of the term. This talk will discuss the results of the Pre- /Post- analysis and outline future directions for the project.

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Chemistry and scientific reasoning: Development and implementation of classroom activities

Justin H. Carmel,, Yasmin Jessa,, Ellen J. Yezierski.Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States

A goal of many chemistry classes for non-science majors is to not only teach content in a context that is pertinent to students' daily lives, but also to encourage them to think critically. Scientific reasoning (SR), an important subset of critical thinking important to scientists, includes being able to examine data, make inferences and generate hypotheses. Typical gains in students' SR ability have been quantified through use of the Lawson Classroom Test of Scientific Reasoning with a historical control. Results have guided the design of the instructional treatment: A series of 15 content-rich, reasoning-focused interventions using a guided inquiry framework. This pedagogical approach has been previously shown to help students' improve their SR skills. Activities were designed to align seamlessly with the course curriculum based on Chemistry in Context, an American Chemical Society publication. A detailed explanation of the nature, development, and testing of the interventions will be presented.

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Using the Redox Concept Inventory (ROXCI) to assess student misconceptions across the particulate and symbolic domains

Allie Brandriet,, Stacey Lowery Bretz.Department of Chemistry & Biochemistry, Miami University, Oxford, OH 45056, United States

Students lack a firm understanding of a topic usually taught during the first semester of general chemistry: oxidation-reduction reactions (redox). Although students construct knowledge from the data obtained by their senses, many textbooks and teachers focus heavily on symbolic equations and rules for determining oxidation numbers as the tools for learning redox concepts. Students can be left with memorized definitions, a superficial understanding, and misconceptions about a complex topic that has a strong particulate foundation. In order to elicit student ideas about oxidation-reduction on a large scale, the Redox Concept Inventory (ROXCI) was created based on 39 semi-structured interviews with undergraduate students. Preliminary data will be collected from general chemistry and organic chemistry students in fall 2013. Findings from the pilot implementation of the inventory will be discussed.

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Analysis of student performance on the Molecular Attractions Concept Inventory

Michael P Bindis,, Stacey Lowery Bretz.Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States

The Molecular Attractions Concept Inventory (MACI) has been implemented with national samples of high school and undergraduate chemistry students. The MACI assessed student understanding of intermolecular forces with questions developed from student responses to interviews involving paper chromatography experiments. The inventory was revised into the current form after a pilot study with a smaller sample of undergraduate students. Results of performance of high school and undergraduate students will be presented, along with statistical measures that illustrate the reliability and validity of MACI. In addition, alternate conceptions of students with regard to intermolecular forces and paper chromatography will be presented.

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Informing practice from assessment results: The assessment as scientific inquiry framework

Jordan T Harshman,, Ellen J Yezierski.Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States

Formative assessment research in science focuses heavily on design, implementation, and validation, but does not elaborate on how teachers should use results of assessments to enhance their teaching practice. This study posits an original framework built from a framework by Calfee and Masuda called the Assessment as Scientific Inquiry (ASI) framework. This framework attempts to elaborate on a step not previously addressed in formative assessment research: The transition from interpretation of data to the instructional decision that is made. Interviews seeking to probe beliefs about original assessments were conducted with several chemistry teachers from a national sample. Interviews aimed to elicit chemistry teachers' beliefs regarding the role of assessment, their interpretation of assessment results, and their justification for the decisions made per that interpretation. In addition, teachers completed the Science Teacher Efficacy and Beliefs Instrument (STEBI) to probe teachers' outcome expectancy. Results regarding the criteria used to determine a conclusion and decision based on the results of teachers' original assessments will be presented.

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CHED 119

Development of a rogue's gallery that illustrates practical errors and potential risks in filtration

J. Martin E. Quirke1,, Jonathan C. Quirke2, Lilia San Miguel1, Mayra Exposito1.  (1) Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States  (2) Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44704, United States

Laboratory textbooks and manuals rarely illustrate what happens when students fail to follow instructions on techniques. Thus, students may not understand why it is necessary to follow instructions. This presentation focuses on errors and, more importantly, the potential risks resulting from improper filtration technique. Fundamental techniques are demonstrated using filtrations for several compounds. However, the principle foci will be filtrations during the recrystallizations of aspirin and acetanilide because these experiments are a common feature in core organic chemistry laboratory classes. The challenges and dangers of hot filtration and vacuum filtration are explored. Among the topics covered are selection of appropriate filter paper, use of sintered glass filters, fluting filter paper, the need for clamping side-arm flasks, vacuum filtration of hot solutions. The potential of the galleries for as a testing tool for pre-laboratory testing exercises are also discussed.

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Minding the gap: The role of general chemistry in organic chemistry student success

Suazette Reid Mooring, of Chemistry, Georgia State University, Atlanta, United States

Organic Chemistry is generally considered a gatekeeper course and the failure rate of the two-semester sequence is high. Our goal is to determine the factors that lead to successful completion and understanding of organic chemistry and to implement interventions to increase student success in organic chemistry. To this end, we are investigating how students' understanding of certain general chemistry concepts affects their performance in organic chemistry. As a first step, chemistry faculty that teach both general and/or organic chemistry were asked their opinion on what general chemistry topics they viewed as important to student success in organic chemistry. Faculty completed a survey to rate commonly presented topics in general chemistry and participated in an interview regarding the role of general chemistry in student success in organic chemistry, and to discuss the rating of general chemistry topics in the survey. The results of the faculty survey and interview are presented.

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Volunteer-based recruitment of future STEM teachers

Gary Lewandowski1, Daniel J McLoughlin2,  (1) Department of Mathematics and Computer Science, Xavier University, Cincinnati, Ohio 45207, United States  (2) Department of Chemistry, Xavier University, Cincinnati, Ohio 45207, United States

This project explores the premise that community service-oriented STEM majors are more likely to be interested -and more successful - in teaching in high-need districts. Xavier University has a history of strong student volunteer contributions to the community. Through an initial NSF Noyce Grant, we will use a community engagement process to identify students that would not have otherwise pursued a teaching career. This process includes connecting an introductory education course to urban education; recruiting STEM majors to tutor in area schools; and creating a summer internship program that provides students with experience teaching STEM topics to underrepresented minorities from local K-12 schools. Both public and private schools are involved, further building on partnerships that will facilitate teacher placement in high-need schools. The summer internships are residential and create a learning community for interns. Competitive Noyce Scholarships will help community service-oriented students complete licensure in their fourth or fifth year.

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Students' understanding of bonding as measured by the Bonding Representations Inventory (BRI)

Cynthia J. Luxford,, Stacey Lowery Bretz.Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States

High school teachers and general chemistry instructors use multiple representations including, Lewis Structures and 3-D manipulatives, to teach the concept of bonding. As students learn to interpret these representations, misconceptions can develop. The Bonding Representations Inventory (BRI) was developed to aid teachers in measuring the prevalence of misconceptions about bonding representations that were detected through student interviews. The BRI was administered to both AP and Non-AP high school chemistry students as well as General Chemistry students. The prevalence of some misconceptions as well as evidence towards the validity and reliability of the data collected with the BRI will be presented.

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Do they bite off more than they can chew? Why do chemistry majors leave?

Jessica M Fautch1,, Randi Shedlosky-Shoemaker2.  (1) Department of Physical Sciences, York College of Pennsylvania, York, Pennsylvania 17403, United States  (2) Department of Behavioral Sciences, York College of Pennsylvania, York, Pennsylvania 17403, United States

In the past decade, undergraduate programs in science, technology, engineering, and math (STEM) have experienced lower enrollment rates and higher and quicker attrition rates. In an effort to determine what factors may predict which students persist in the STEM majors, relative to students who move to other majors, we are conducting a longitudinal study following chemistry (STEM) and psychology (non-STEM) majors during their first year of college. This interdisciplinary study is a preliminary investigation into why students choose to leave STEM majors. Participants complete surveys at three time points and academic performance is recorded at five time points. Following this pilot study, the research will be extended to other STEM programs in an effort to be more inclusive of all STEM majors across campus. Additionally, data collected from the pilot study may help design interventions for identifying students who struggle in STEM majors, possibly leading to increased retention college-wide.

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Promoting science with K-12 students through southern West Virginia

Joshua H Kim,, Emily M Wood, Micheal W Fultz.Department of Chemistry, West Virginia State University, Institute, West Virginia 25112, United States

Undergraduate students at WVSU have been incredibly active over the last academic year enhancing science education throughout the southern West Virginia region. These actives include working with all age groups in the K-12 public and private schools and community groups. These students have become “Ambassadors for Science” and are mentoring younger students on how to reach into the community. New like science bowls and sponsoring lab days at elementary schools have been established and older programs in public education are reinvented with the help of able minds and generous fundraising activities. New ideas and relentless pursuit of excellence will continue as long as enhancing science education through hand-on activities is needed.

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Study of the traditional science programs through surveys, focus groups, and a workforce conference

Micheal W Fultz1,, Gail Mosby2, Frank Vaughan3, Gary Adams4.  (1) Department of Chemistry, West Virginia State University, Institute, West VIrginia 25112, United States  (2) Department of Sociology, West Virginia State University, Institute, West Virginia 25112, United States  (3) Department of Political Science, West Virginia State University, Institute, West Virginia 25112, United States  (4) Office of Sponsored Programs, West Virginia State University, Institute, West Virginia 25512, United States

Upon being awarded an NSF-Historically Black College or University (HBCU) grant for a study on the performance of the College of Natural Sciences and Mathematics the college performed a multistep process to collect the best information available. This study included a survey series on current students, prospective students, faculty and staff on the strengths and weaknesses of the College, new programs and concentrations that should be offered, career preparation, and community outreach. The second study was a series of focus groups with all majors individually, faculty, alumni, and current employers on how we can strengthen the college. The third step was a workforce conference bringing academia and industry together too better communicate how we can better work together to strengthen the region. This study will greatly alter the way the college will recruit, retain, and train students.

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Using Panopto to create media for chemistry classes via screen capture

John G. D'Angelo, of Liberal Arts and Sciences, Division of Chemistry, Alfred University, Alfred, NY 14802, United States

We have been using the screen capture program Panopto to create various course adjuvants for organic and general chemistry courses. Among the uses are to create preparative videos for group work assignments, video-based homework keys and recording live lectures for archiving. Panopto has also been used to create deomonstration videos of how to use electronic resources such as chemical drawing programs and Scifinder Scholar. Preliminary feedback from students and difficulties encountered will be presented.

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Analysis of novices' understanding of events in electrolytic solutions

Juliet A Hamak,, Resa M Kelly.Department of Science Education, San Jose State University, San Jose, CA 95112, United States

A central component of learning general chemistry involves understanding equations and formulae to solve problems. Often times, students are deemed competent in their understanding of chemistry concepts when they are able to solve algorithmic problems. This belief has been challenged by researchers (Kelly et al., 2009; Sirhan, 2007; Pinarbasi & Canpolat, 2003; Smith & Metz, 1996) who have studied students' difficulties in making connections between the algorithmic problem solving methods and the dynamics of chemical reactions. The question is what do students really understand about the conceptual nature of laboratory activities, and how do they draw connections to formulae and equations? Prior to learning about precipitation reactions, where symbolic equation patterns are emphasized, some teaching materials suggest having students examine the electrolytic behavior of substances to inform students of the submicroscopic details of substances. The goal of this study was to learn the kinds of key features and misconceptions first semester general chemistry students portrayed in their written, drawn and oral descriptions of substances tested for conductivity. Data collection involved student volunteers completing worksheets and performing several simple microscale solution conductivity activities using aqueous solutions of varying conductivity. The students were observed and interviewed while performing the demonstrations to gain insight into their understanding and ability to make connections between the macroscopic (visible to the naked eye) and submicroscopic (atomic level) aspects of the laboratory activities. Insights from this study, including implications for teaching and animation design will be shared.

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Counterfeit drugs: Teaching three organic chemistry laboratory techniques using a two week scenario

David Soulsby, of Chemistry, University of Redlands, Redlands, CA 92374, United States

Two thematically linked discovery-based first semester organic chemistry laboratory experiments have been developed that introduce extraction, crystallization, and melting point using a counterfeit drug scenario. In the first week students use filtration and acid-base extractions to separate their possible counterfeit drug into three separate compounds. At this stage a simple chemical test establishes the identity of one of the compounds. In the second week of the experiment students crystallize the remaining compounds and use melting point to determine their identities from a list of possible candidates. Each student then determines whether they have analyzed a counterfeit or genuine drug. By integrating this scenario at the beginning of our laboratory sequence we have found that our students have a better understanding of extraction, crystallization, and melting point, and are better able to apply these techniques to later experiments.

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Incorporation of liquid chromatography-mass spectrometry into the undergraduate chemistry curriculum

Kevin H. Bennett, of Chemistry, Hood College, Frederick, Maryland 21701, United States

Liquid Chromatography-Mass Spectrometry (LC-MS) instrumentation has been intergraded into the undergraduate chemistry curriculum at Hood College. The goal of this work was to improve student understanding of separation and detection methods through experiments involving a wide range LC-MS techniques. Concept development experiments in our lower-level classes provided students a foundation of separation and detection knowledge. As students progressed through the curriculum they expanded and reinforced key concepts in increasingly more complex and detailed experiments. Experiments were developed for General Chemistry, Organic Chemistry, Quantitative Analysis, Instrumental Analysis, Physical Chemistry, and Biochemistry. Additionally an experiment was developed for inclusion into the non-science majors College Honors program. Research projects in the Departments of Biology and Chemistry and Physics have also been impacted by access to LC-MS instrumentation. Challenges of integration of complex instrumentation across the curriculum will be discussed.

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Greenhouse gases capture and storage: Chemistry for clean air

Odette Esam, Aleksey Vasiliev, of Chemistry, East Tennessee State University, Johnson City, TN 37614, United States

Greenhouse gases from industrial sources in atmosphere contribute to greenhouse effect leading to climate change. The experiment was developed for visualization of technology of their sequestration and storage. In the model equipment for carbon dioxide capture, CO2 was adsorbed on porous materials obtained in our laboratory by grafting and sol-gel synthesis. By the first method, the materials were prepared by immobilization of organic trimethoxysilanes containing amino groups on the surface of porous silica gel. The second method was based on polycondensation of the same monomers in acidic media in presence of a surfactant. A mixture of CO2 with nitrogen passed through the reactor filled with an adsorbent at room temperature. Then, the temperature of the reactor was increased to 120 °C, CO2 desorbed from the adsorption sites and was captured by a barium hydroxide solution. The effectiveness of each adsorbent was calculated from the mass of precipitated barium carbonate.

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Green acetylation of ferrocene using conventional microwave synthesis

Sarah E. Goergen,, Chase T. Gerold,, Ted M. Pappenfus, of Science and Mathematics, University of Minnesota, Morris, Morris, MN 56267, United States

The acetylation of ferrocene is a highly researched topic in the undergraduate laboratory setting involving a Friedel-Crafts reaction. Previous methods for acetylating ferrocene use conventional thermal heating or laboratory grade microwave ovens and Nafion (an expensive polymer). Since microwave synthesis is becoming increasingly popular in laboratory experiments for their reduced solvent use and quick reaction times, a practical and inexpensive lab was developed. This method uses a conventional microwave and a solvent free, one-pot microscale reaction. When compared to previous methods, this method is more undergraduate-level friendly due to the convenience of the procedure and availability of the materials. The goal of the experiment was not to completely acetylate ferrocene, but to have a mixture of ferrocene, acetylferrocene, and diacetylferrocene. By having a mixture, students are able to purify and characterize their reaction mixture using numerous techniques, including column chromatography, TLC, HPLC, GC-MS, FT-IR, and NMR. Using response factors calculated during the developmental stage, a 1:1:1 ferrocene:acetylferrocene:diacetylferrocene mixture, students are able to use HPLC to determine the relative amounts of these compounds in their crude reaction mixture. The process by which acetylferrocene was synthesized will be integrated into the organic chemistry laboratory curriculum at the University of Minnesota, Morris.

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Quantum interference: How to measure the wavelength of a particle

Joseph M. Brom,, University of St. Thomas, St. Paul, MN 55105, United States

We describe a quantum experiment suitable for an upper-division laboratory course in physical chemistry. The experiment consists of preparing an initial quantum state of a photon using a laser source, single-slit apparatus. At the detector, students measure the probability that the photon will pass through the single-slit with momentum component px = p sin Θ, where p is the momentum and Θ is the scattering angle of the photon. Due to the fact that the initial quantum state of the photon is a superposition of position eigenstates, quantum interference effects are directly observed and measured. Performing a Fourier transform of the photon wavefunction from position space to momentum space allows the student to measure the so-called wavelength of the quantum particle, i.e., the photon.

CHED 135

Using a guided inquiry and experimental approach to teaching buffers in general chemistry

Teresa L. Longin, of Chemistry, University of Redlands, Redlands, CA 92373-0999, United States

Buffers are important in chemistry, biology, and environmental studies. Understanding
what buffers do and why, how to design and prepare buffers, and the limits on buffering
capacity are vital concepts. In this approach, a guided inquiry activity leads students through a theoretical understanding of buffers and ends with students designing a buffer system to
achieve a specific pH. This segues into a lab experiment in which the students use their design to prepare and adjust a buffer solution to the desired pH. They add aliquots of strong acid or base to their buffer while monitoring pH to directly determine the buffering capacity of their system. The combination of guided inquiry and laboratory experiment engages the students in learning the fundamentals of buffers and provides them with hands-on experience in creating and testing buffers, reinforcing the concepts.

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Cost-effective titration instrumentation for the chemistry laboratory using inexpensive open-source microcontrollers

An-Phong Le,, Jonathan Smith.Department of Chemistry and Physics, Florida Southern College, Lakeland, Florida 33801, United States

Computer-interfaced instrumentation is commonplace in research laboratories, but their integration into high school and undergraduate laboratories can be costly (putting further strain on already tight budgets). The recent availability of inexpensive microcontrollers presents opportunities to develop this instrumentation in-house at a fraction of the financial cost of commercially available alternatives, but this comes at a cost of time and so-called “sweat equity.” To this end, we are interested in developing and distributing plans for inexpensive computer-based instruments for the instructional laboratory. As a demonstration, we have interfaced a standard pH electrode and a homebuilt infrared drop counter to an ArduinoTM microcontroller to create a data logger capable of recording both titrant delivered and solution pH in real-time. These sensors can be assembled by students, and the adaptation and improvement of these devices could be an exciting enrichment activity for students interested in electronics or as projects for industrial arts classes.

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Microbial secondary metabolism in the biochemistry teaching lab

Tanya L. Schneider, of Chemistry, Connecticut College, New London, CT 06320, United States

A semester-long project-based series of laboratory experiments was developed in order to engage students in the second semester of introductory biochemistry. The lab project centered on characterizing microbial enzymes important for the biosynthesis of clinically used secondary metabolites, therefore linking the lab experience to the overall course focus on metabolism. Students were able to make choices and develop portions of the project, and learned current techniques such as site directed mutagenesis, affinity purification of proteins, and enzyme activity assays. The class responded favorably to the project topic, understanding that they were investigating novel areas of inquiry and investing more in their work than when assigned more formulaic lab experiments.

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Linking chemistry and biology courses through research on anticancer ruthenium complexes

Laura K Stultz1,, Pamela K Hanson2.  (1) Department of Chemistry, Birmingham-Southern College, Birmingham, AL 35254, United States  (2) Department of Biology, Birmingham-Southern College, Birmingham, AL 35254, United States

Numerous studies have shown that undergraduate research significantly enhances a student's educational experience. Here we describe an NSF-funded project aimed at integrating research into introductory and upper-level chemistry and biology courses at Birmingham-Southern College. Specifically, undergraduates in a 100-level chemistry course synthesize anticancer ruthenium complexes and characterize the stability of these drugs under a variety of experimental conditions, such as variable pH, temperature, and ion concentration. Students in a 100-level cell and molecular biology course then use budding yeast as a model organism to quantify the mutagenicity and toxicity of these drugs under similar conditions. Results from these introductory courses will shape the experimental design process for upper level biology and chemistry students who will conduct phenomic screens, measure drug uptake, and analyze drug-DNA interactions. We anticipate that this approach to STEM teaching and learning will lead to a measurable improvement in the ability of students to articulate cross-disciplinary concepts.

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Rearrangement reactions of epoxides derived from (R)-pulegone in an advanced organic laboratory

Larry G. French, of Chemistry, St. Lawrence University, Canton, NY 13617, United States

Diastereoisomeric epoxides are prepared from (R)-pulegone, isolated from pennyroyal earlier in the course, via reaction with hydrogen peroxide under basic conditions. Students then explore two rearrangement reactions of these epoxides; one catalyzed by a protic acid and the other by a Lewis acid, and determine the major product(s) from each reaction. The p-toluene sulfonic acid mediated process affords predominately 2-hydroxy-5-methyl-2-(1-methylethenyl)-cyclohexanone as a mixture of two diastereoisomers. Treatment with boron triflouride etherate affords a single product, (5R)-2,2,5-trimethyl-1,3-cycloheptadione, in high yield.

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Photographic evidence for the mechanism and regiochemistry of Markovnikov and anti-Markovnikov additions of hydrogen bromide to alkenes

Jesse E. Pulido1,, David A. Becker1, Jonathan C.K. Quirke2, J. Martin. E. Quirke1.  (1) Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States  (2) Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, United States

This is part of an ongoing project to provide photographic evidence for the outcome/mechanisms of most core organic chemistry reactions. 11-Undecenoic acid was used to probe anti-Markovnikov reactions with colorful evidence for radicals obtained using an azulenyl nitrone radical trap prior to addition of HBr. After adding gaseous HBr to the substrate in the presence of benzoyl peroxide, the product was isolated and characterized as the expected 11-bromoundecanoic acid. Photographic evidence for the product was obtained by melting point, positive Finkelstein test and a negative test with ethanolic AgNO3. Challenges in obtaining the Markovnikov adduct are discussed. For Markovnikov addition, 2-ethyl-1-butene reacted with gaseous HBr to form 2-bromo-2-ethylbutane. Photographic evidence was obtained by boiling point, negative Finkelstein test and formation of a precipitate with ethanolic AgNO3. Challenges of obtaining the anti-Markovnikov product by repeating the reaction in the presence of peroxide are discussed. Pedagogical benefits of the work are described.

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Exploring electrolytic products of water for the quantitative analysis of supplement tablets

Christopher J Scanlon,, Rajeev B Dabke.Chemistry, Columbus State University, Columbus, GA 31904, United States

An undergraduate experiment for the analysis of vitamin C in a commercial supplement tablet is presented. In this experiment, we constructed an electrolysis cell. Electrolytically produced I2(aq) oxidized ascorbic acid to dehydroascorbic acid. Starch was used as a visible indicator to detect the end point of the titration. A measured volume of potassium hydrogen phthalate (KHP) was added to the cathode compartment. Electrolytically generated OH-(aq) neutralized KHP. Phenopthhalein was used as a visual indicator. Electrolysis process was continued until corresponding end point is reached in both compartments. From the amount of KHP added to the cathode compartment, the moles of OH-(aq) and moles of I2(aq) generated in the anode compartment were determined. From the stoichiometric relations, moles of ascorbic acid in a supplement tablet were quantified. Detailed experimental procedure, construction of the electrolysis cell, and results will be presented.

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Evaluating the evidence: Determining the course of a Diels-Alder reaction using visible spectroscopy

Jonathan Rhoad, of Chemistry, Missouri Western State University, Saint Joseph, MO 64507, United States

An essential skill for chemists is analyzing evidence to determine the outcome of the reaction. Too often our teaching lab experiments predict for the students what that evidence should look like, and the students can determine “did I get the right answer?” In this experiment students react p-benzoquinone with cyclopentadiene. The visible absorbance of the reaction at several wavelengths is observed using a Microlab®. The students are then asked to determine what reactions are occurring.

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Study of the methyl formate decomposition

Hafed A Bascal,, The University of Findlay, Findlay, Ohio 45840, United StatesChemistry, The University of Findlay, Findlay, Ohio 45840, United States

The thermodynamic data of oxygenated species, such as methyl formate, are not as well studied as those of standard hydrocarbon fuels. However, these data are of essential in the development of chemical kinetic models, particularly in the combustion of oxygenated fuels. As most of the available rate parameters are derived from the study of conventional hydrocarbon fuels. Moreover, oxygenated fuels can exhibit unfamiliar bond dissociation energies, especially these bonds that are in close proximity to the electronegative oxygen atoms. In this work calculated thermodynamics data of the major species in the decomposition of Methyl Formate will be presented.

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Incorporating nanotechnology based laboratory experiments into first semester general chemistry

David S Heroux,, Benjamin Murphy.Chemistry, Univ. of Maine at Farmington, Farmington, ME 04938, United States

Many colleges and universities are now implementing an Atoms-First methodology to first year chemistry instruction. This change provides a great opportunity to incorporate nanotechnology-based experiments. The use of nanotechnology-based laboratories addresses two issues. First, since Atoms-First teaching constitutes building upwards from electrons, to atoms, to molecules and then to reactions, many traditional, early first-semester labs are best used later in the semester. This is not the case with many nanotechnology-based experiments, which can be understood without thorough exposure to general chemistry topics. Secondly, nano-based experiments introduce students to exciting and modern applications of chemistry in ways not typically illustrated in traditional early semester labs. Therefore, the use of nanotechnology based experiments allow the instructor to lay fundamental principles of chemistry in lecture while students do experiments in lab that builds interest in chemistry. The experiment presented in this poster could also be adapted to any general chemistry courses.

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Development of an advanced NMR-centered undergraduate interpretive spectroscopy course

William F. Wacholtz,, Brant L. Kedrowski, of Chemistry, University of Wisconsin Oshkosh, Oshkosh, WI 54901, United States

Most senior-level undergraduate interpretive spectroscopy courses offer a curriculum taught from an organic-centric perspective that covers the three basic spectroscopic techniques of infrared (IR), gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR). Our approach was to team teach an interpretive spectroscopy course using both an inorganic and organic perspective focusing more on NMR spectroscopic techniques as the central tool for structural analysis and identification. Throughout the course inorganic as well as traditional organic examples were employed in all lecture, laboratory and assessment aspects of the course. Through an integrated lecture and laboratory experience, which employed online (D2L©) examples of real-world analysis problems, students were introduced to increasingly more sophisticated spectroscopic techniques. The course was structured such that technique-based laboratory experiences were interspersed with unknown identification-based problems. A syllabus and course materials with laboratory experiments will be presented and made available at the poster session.

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iExperiment: Incorporating mobile technologies into the chemistry laboratory

Diana Hoover, of Natural and Health Sciences, Seton Hill University, Greensburg, PA 15601, United States

Technology has revolutionized the collection, recording, and analysis of data. iPads and laptop computers can be used in the teaching laboratory for recording and plotting experimental data in real-time. A grant from the Spectroscopy Society of Pittsburgh was used to purchase portable instruments manufactured by Vernier. These instruments operate with LoggerPro software that can be installed on student-owned laptops. The incorporation of portable instrumentation and mobile technology into chemistry laboratory courses at a private, four-year liberal arts university will be highlighted in this poster.

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Incorporation of a “design thinking” facilitated activity to improve student learning in undergraduate chemistry courses

Teresita Munguia,, Charles A Smith, of Chemistry, Our Lady of the Lake University, San Antonio, Texas 78207, United States

Students in both advanced and introductory chemistry courses at Our Lady of the Lake University performed an activity assimilated from “Design Thinking” in order to sequester hurdles which hinder their learning in an OLLU Chemistry course. In the activity students began by gaining empathy by interviewing another student in the class. The paired students defined and identified hurdles that prevented academic success in their chemistry course. Students conceived multiple solutions and presented their solutions or prototypes to the class. Favorite prototypes were then incorporated into the course the following semester.

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Simple continuously extracting steam distillation apparatus for the organic laboratory

Karl P. Peterson,, Ross Jilk.Department of Chemistry, University of Wisconsin-River Falls, River Falls, WI 54022, United States

A simple and efficient apparatus for steam distillation that is based on an inexpensive modification to a standard fractional distillation apparatus and a separatory funnel has been developed. The apparatus has been successfully used to isolate essential oils from three natural sources. Eugenol has been isolated from ground cloves as part of a multi-week project in our freshman organic chemistry laboratory course. Students isolate the essential oil by steam distillation, analyze the oil using thin-layer chromatography, separate the components of the oil by acid-base extraction, evaluate the antibacterial activity of the crude oil and the separated components using a Kirby-Bauer assay, and then characterize that antibacterial component (eugenol) using GC-MS, IR and 1H NMR. Additionally, we have isolated cinnamaldehyde from ground cinnamon and anethole from ground anise seeds. In each case the essential oil is isolated in a form that is pure enough to allow for characterization by GC-MS, IR and 1H NMR. We have used this exercise as a follow-up to the introduction to spectroscopy in our sophomore organic laboratory course.

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Nucleophilic substitution reactions using phosphine nucleophiles: An introduction to 31P NMR

Paul A Sibbald, of Chemistry, Stetson University, Deland, Florida 32723, United States

The use of nuclear magnetic resonance spectroscopy (NMR) to monitor reactant to product ratios is a commonly used technique in modern synthetic chemistry. However this approach is not often utilized when introducing nucleophilic substitution reactions in undergraduate labs as these reactions are traditionally taught prior to discussing modern spectroscopy techniques such as NMR. This limits an instructor's ability to illustrate important concepts such as relative electrophile and nucleophile reactivity through quantitative means.

A new undergraduate lab is described using 31P NMR spectroscopy to monitor product formation for a number of different alkyl halide electrophiles and phosphorus nucleophiles. Students are able to use reactant to product ratios obtained by simple 31P NMR to explore the relative reactivates of these compounds.

CHED 151

Student bonding and coordination

Carolina Costa Farris, Carson De-Priest,, Lisa Orr,, Andrew Cornell,, Jerry Darsey.Department of Chemistry, University of Arkansas at Little Rock, Little Rock, AR 72204, United States

With the support from the Chemistry Department, the Student Organization of the American Chemical Society at the University of Arkansas at Little Rock (UALR) has continued to grow in strength and size around the campus. This year, the goal of the organization has been to increase student involvement. By continuing with previously implemented programs, such as the partnership between the university and a local school, encouraging student involvement with undergraduate research, and providing free tutoring services, UALR ACS remains as an important chapter of the lives of the Chemistry majors and minors in Little Rock. With the participation of faculty members and graduate students, our monthly meetings provide relevant Chemistry topics to undergraduate students, who enjoy free lunches and networking opportunities during the meetings. Our organization is also participating in events such as the Color Run, a national 5km race which supports charitable organizations.

CHED 152

Project-based experiments in the quantitative analysis lab: Determination of the calcium content in an “artifact”

Sara E Hubbard, of Chemistry, Ouachita Baptist University, Arkadelphia, Arkansas 71998, United States

In the quantitative analysis laboratory, we seek to aid students in the development of their laboratory skills while also exposing them to real-world topics. This project requires students to research possible methods for calcium determination and discuss the pros and cons of each. Each group of students submits a project proposal for the determination of calcium in an “artifact” using two methods of analysis. Techniques include EDTA titration, gravimetric analysis, AA, and UV-Vis absorption. The groups spend several lab periods performing their analyses, culminating in an oral presentation of their findings to their classmates and the faculty. This capstone to the quantitative analysis lab experience allows students to bring their wet and instrumental lab skills together while learning to compare the effectiveness and efficiency of techniques for a real-world sample that limits the amount of analyte they can use.

CHED 153

Statistical analysis of the efficacy of online learning in general chemistry at the University of Washington

Jan Irvahn2, Jacob Parikh1, Andrea Carroll1, Philip J Reid1, Colleen F Craig1,  (1) Department of Chemistry, University of Washington, Seattle, Washington 98195, United States  (2) Department of Statistics, University of Washington, Seattle, Washington 98195, United States

We present the results of a linear regression of exam scores for students in general chemistry versus performance in two online learning systems: WebAssign, which presents problems in a traditional manner, and ALEKS (Assessment and LEarning in Knowledge Spaces), which is an adaptive, tutorial-based system. Comparisons are made for students taking the same general chemistry course, taught by the same instructor, in the same quarter in subsequent years, where WebAssign was used one year, and ALEKS the next. We find that in WebAssign, a 1 point difference in homework score corresponded, on average, to a 0.46 point difference in final exam score (95% CI: 0.36, 0.56). In ALEKS, a 1 point difference in homework score corresponded, on average, to a 1.06 point difference in final exam score (95% CI: 0.98, 1.15). Controlling for gender and SAT scores did not change the overall conclusion.

CHED 154

Development of a reciprocating college and university speaker series between local sections in Georgia

Kevin M. Bucholtz, of Chemistry, Mercer University, Macon, GA 31204, United States

An American Chemical Society Local Section Innovative Programs (IPG) grant was awarded to develop a reciprocating speaker series at the undergraduate colleges and universities in central and southern Georgia (Local Sections 410, 416, 454). These three local sections do not have chemistry Ph.D. granting institutions in their section but are characterized by 12 smaller undergraduate institutions including three Historically Black Colleges and Universities (HBCUs) and a women's college. Implementation of the program has resulted in participation by six colleges and universities in three sections (410, 416, 454). During the spring semester of 2012, a total of ten seminars by six speakers were given as a result of the program. This program has provided an excellent opportunity for faculty to interact with other faculty from similar schools and provides students with a broader exposure to chemical research topics.

CHED 155

Utilizing 31P NMR spectroscopy in undergraduate general chemistry courses as an early introduction to modern chemical characterization

Richard M. Coulson, John T. York, of Chemistry, Stetson University, DeLand, FL 32723, United States

NMR spectroscopy is widely regarded as one of the most important tools in modern chemistry. However, while many laboratory experiments teach students the details of 1H and 13C NMR spectroscopy at the sophomore organic chemistry level, few tools exist for introducing students to this crucial technique at the introductory general chemistry level. We present here a new laboratory experiment in which first-semester general chemistry students collect and interpret the 31P NMR spectra of a series of different PR3 compounds (where R = aryl and alkyl substituents). By interpreting and comparing 31P NMR spectra, students gain insight into important NMR concepts including chemical shift, peak integration, and the use of internal standards, while avoiding much of the potential confusion involved in the similar study of 1H NMR spectra. This early introduction to modern NMR spectroscopy prepares students for the use of the technique in more advanced ways in subsequent courses.

CHED 156

Establishing new bonds: The ACS-RUM family

Sherry Rivera,, Jorge Rullán,, Natasha Santos-Piñero,, Félix Rodríguez,, Samantha González,, Héctor Ocasio,, Orlando Vázquez,, Jamil Silva,, Diego Navarro,, Nilka Rivera, of Chemistry, University of Puerto Rico, Mayaguez, Puerto Rico

The American Chemical Society has been in our Campus since 1954, making this year its 58th anniversary. Since then, we have been helping our members develop their academic and professional skills. This year we have taken the unification of the chapter, which has more than 120 members, as our mission. We do so through a series of activities involving chemistry and its different faces and increasing the participation of every member, not only in the activities, but also in their planning and organization. Those include, but are not limited to, conferences, workshops, the National Chemistry Week, new members Initiation Ceremony, school demonstrations, charities and social activities. Doing all these activities we all work together as a big family. Throughout the year, we have seen the promising development and unification of the members, forming the family we have sought for.

CHED 157

Optimizing trade-offs: The integrated lecture-laboratory in instrumental analysis

Nolan T Flynn, of Chemistry, Wellesley College, Wellesley, Massachusetts 02481, United States

Instrumental analysis courses enable students to gain an understanding of instruments used to probe chemical systems. These courses often provide a detailed understanding of the underlying principles of electronics and circuitry, data acquisition and processing, and relevant figures of merit while working with a variety of instruments. Many of the skills and much of the content presented in the instrumental analysis class is, by its very nature, hands on. However, the traditional format of separate lectures and laboratories makes maximizing time for these experiences challenging. To mitigate this difficulty, we have used the integrated lecture/lab format, blending hands on activities, including those akin to lab experiments, with lecture/discussion. Using two 3 hour blocks per week has provided ample opportunity for active student learning. We will present salient outcomes for both instructor and students.

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CHED 159

Thermodynamic study of solute partitioning: A second-semester chemistry experiment

William Steel, Sciences, York College of Pennsylvania, York, PA 17405, United States

The partitioning behavior of molecular iodine in liquid-liquid systems composed of water and an organic solvent has been used in the general chemistry laboratory curriculum to explore the concepts of thermodynamics. Working in small groups, students use UV-vis spectroscopy to observe and quantify the iodine partitioning in several systems (in the form [I2]org/[I2]aq), each of which begins with a different concentration of dissolved iodine. Further, each group conducts their work at a unique temperature. Compiling and analyzing the class' temperature-dependent data allows students to calculate the enthalpy and entropy changes that accompany the movement of molecular iodine across the liquid-liquid interface. Optional features of the experiment include comparison to thermodynamic values calculated from molecular modeling programs and utilization of different liquid-liquid interfaces to observe the effect of the organic solvent on the resulting behavior.

CHED 160

What are the core chemistry concepts?

T. Wade Killingsworth, of Chemistry and Biochemistry, California State University Chico, Chico, CA 95929-0210, United States

What are the most valuable, fundamental, deep, central chemistry concepts? A review of some publications on this topic will be presented. A proposed answer to the above question will be given in the form of a list and a map. Issues with and uses of the list and map will be discussed.

CHED 161

Power of affective factors (self-efficacy, motivation, and gender) to predict chemistry achievement with the benefits of knowledge surveys on metacognition level

Xin Wu1,, Elzbieta Cook2.  (1) College of Education, Louisiana State University, Baton Rouge, LA 70803, United States  (2) Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, United States

Self-efficacy, gender, and motivation are subjective predictors of students' academic achievement. Self-assessment prompted by knowledge surveys involves metacognition,i.e., students' awareness of how they learn. Knowledge surveys can be used to measure changes in students' achievement level and to assist students in content review and inspire reflection on one's ability to learn. In this work, we combine the above predictors into the survey to determine whether achievement in general chemistry can be forseen. Our research was conducted on 700 students enrolled in General Chemistry I classes (Chemistry for science majors) at Louisiana State University. The online survey was administered during the last week of classes. Data were analyzed via descriptives, correlation, linear and multiple regression statistical analyses with the correlation of grades on Exam 1 and the final exam. The three predictors are ranked in terms of their significance in predicting achievement in chemistry.

CHED 162

Physical chemistry lab experiment: Silver nanoparticles influence on the fluorescent properties of ruthenium(II) tris(bipyridine) chloride

Timothy R Brewer,, Eastern Michigan University, Ypsilanti, Mi 48197, United States

A physical chemistry laboratory was designed to synthesize various sizes of silver nanoparticles and study their effects on the fluorescence of the dye ruthenium(II) tris(bipyridine) chloride. Nanoparticles were synthesized in the size range from 10 to 50 nm using previously published methods. The fluorescent quenching effect of different sizes of nanoparticles was investigated through the use of a Stern-Volmer plot of fluorescence intensity versus concentration of nanoparticle. Experimental results indicated a size-dependent quenching constant with larger nanoparticles exhibiting a larger quenching rate constant. The other significant experimental result was that for a constant concentration of nanoparticles, the fraction of dye absorbed on larger nanoparticles increased as the size of the nanoparticles increased. These results can be attributed to the nanoparticle's surface area.

CHED 163

Kinetics of reaction of potassium hydroxide with 2,6-bis(3-bromobenzylidene) cyclohexanone in 50% acetonitrile - 50% water

Nicole Berry,, Eric Reinheimer.Chemistry, Cal Poly Pomona, Pomona, California 91768, United States

The current interest in the synthesis of α,β-unsaturated dibenzylidene ketones such as (2E, 6E)-2,6-bis(3-bromobenzylidene)cyclohexanone 1 is their antitumor properties. Although there is sufficient literature supporting these properties, there are a limited number of reactivity studies of such compounds. The goal of this project focuses on kinetic studies of 1 . Kinetic data will be collected using UV-Vis spectroscopy which will follow the reaction of 1 with varying concentrations of potassium hydroxide solutions in aqueous acetonitrile to determine the reactivity of the β-carbon. Preliminary kinetic results will be presented.

CHED 164

Expanding knowledge of chemistry at Roger Williams University and the surrounding community

Christina Fontana,, Courtney Dennis,, Stephen O'Shea, Clifford Murphy.Department of Chemistry, Roger Williams University, Bristol, Rhode Island 02809, United States

Roger Williams University Student Affiliates began the academic year with a school-wide exhibition of homemade liquid nitrogen ice cream to garner student interest in chemistry and the RWU ACS affiliate chapter as a social outlet. The affiliates attended RI ACS local section fall meeting at which Dr. John P. Jasper spoke about industrial batch auditing and process patent protection. As part of the group's effort to promote chemistry, at RWU late night programming Roger After Dark we presented chemistry demonstrations; elephant tooth paste, super conductor, flame test. Additionally the RWU ACS chapter produced a week long mural display to educate students on sources of renewable energy through chemistry. We have extended our outreach activities to include performing chemistry demonstrations at local high schools students via in-class demonstrations focusing on green chemistry such as a looking into phosphate versus non-phosphate cleaning products.

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CHED 166

Regulated expression of green fluorescent protein in Escherichia coli: An advanced biochemistry lab

Steven J Cok, of Chemistry and Food Science, Framingham State University, Framingham, MA 01701, United States

The advanced biochemistry course at Framingham State University includes an experiment on regulation of gene expression. In order to enhance the students' understanding of regulation of gene expression and promote student driven experimental design, we have used the pGlo gene expression vector from BioRad to evaluate regulation of the arabinose operon by various carbohydrate sources. The gene encoding green fluorescent protein(GFP) was under the control of the arabinose operon. Student designed experiments were generated to measure increased expression of GFP by arabinose, determine the stereospecificty of regulation and test whether other common sugars affected gene expression. Extensions of this laboratory exercise included testing repression of GFP expression by glucose in a concentration dependent manner. Evaluation of student success and potential pitfalls will be presented.

CHED 167

SCIENCountErs: Teaching and learning science at the local boys and girls clubs

Elvin A. Morales,, M. Francisca Jofre, John W. Moore, Andrew E. Greenberg.Department of Chemistry, University of Wisconsin: Madison, Madison, Wisconsin 53705, United States

The SCIENCountErs outreach program is organized and run between the Institute for Chemical Education (ICE) and the Boys and Girls Clubs (B&GC). The program was established in 2005 in collaboration with the UW–Madison Nanoscale Science and Engineering Center (NSEC). The aim of SCIENCountErs is to inspire and excite a diverse audience of future scientists and engineers. These goals are achieved by presenting hands-on science and engineering activities, using a guided-inquiry approach. This presentation will go over the program's goals, pedagogical model, impact on the community, and plans for statewide and nationwide expansion.

CHED 168

Introducing quality assurance practices in the analytical chemistry instructional laboratory

Sharyn Miller,, Dan Sykes.Forenisc Science Program and Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States

Quality assurance is an important routine practice in industry-oriented environmental and toxicology labs. In academia, analytical chemistry curricula often provide a cursory overview of such practices in lecture and even less exposure in the laboratory. A laboratory experiment was developed around the analysis and quantitation of synthetic cannabinoids in herbal incense products using GC-MS which introduces students to the theory and practial application of quality assurance as practiced in industry. The experiment employs external and internal standards for quantitation and the use of check, performance, recovery and surrogate standards for method validation.

CHED 169

Implementation of a framework for effective chemistry demonstrations

Jerome E Haky1,, Donna Chamely-Wiik1, Mari Heghinian1, Deborah Louda2, Nancy Romance3.  (1) Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States  (2) College of Medicine, Florida Atlantic University, Boca Raton, Florida 33431, United States  (3) Department of Teaching and Learning, Florida Atlantic University, Boca Raton, Florida 33431, United States

As part of a National Science Foundation's GK-12 program that enables graduate students in science, technology, engineering and mathematics (STEM) to interact with students and teachers in K-12 science classes, we have developed a framework for creating pedagogically sound Chemistry demonstrations that allows for easy implementation and flexibility. This SQER3 framework, Survey, Question, Experiment, Recite, Reflect and Review, is an interactive, question-driven model that draws clear parallels to actual science practices. This approach also enables students to extend their investigations through cyclical rounds of additional questions and experiments. We have adapted several conventional demonstrations to the SQER3 framework. Preliminary results in high school classes indicate that utilizing this model is effective in enhancing student learning of chemistry concepts and principles.

CHED 170

Kinetic vs. thermodynamic control: Slow movement to a new paradigm

David Oostendorp,, Adam Moser.Division of Molecular and Life Sciences, Loras College, Dubuque, IOWA 52001, United States

Organic Chemistry textbooks have long used the addition of HBr to 1,3-butadiene as a classic example of kinetic vs. thermodynamic control. At high temperatures the thermodynamically favorable 1,4-addition product predominates. At low temperatures, the less stable 1,2-addition product predominates. The traditional explanation for this is that the activation energy of the 1,2-addition is lower, thus its rate is faster. Some texts, citing a 1979 experiment by Eric Nordlander, are stating that the real reason is what is being called a proximity effect. We are currently charting and will report on the movement towards this explanation in textbooks. We are using experimental and computational methods to further refine the role the two explanations play in the reaction.

CHED 171

Integrating electronic data collection and web-based storage into a protein denaturation experiment in the biochemistry teaching laboratory

Scott M Tremain, of Chemistry, University of Cincinnati, Blue Ash College, Blue Ash, OH 45236, United States

A vital component in the biochemistry laboratory curriculum is absorbance and fluorescence spectrophotometry. Our traditional biochemistry experiments utilize single-wavelength spectrophotometers that are not capable of collecting absorbance spectra data efficiently. Furthermore, a fluorimeter is not readily available. The MeasureNet electronic data collection system consists of a central computer connected to a network of 15 student workstations. Each workstation (outfitted with various probeware) records real-time data that can be saved and uploaded to a web-based storage site accessible to the student from anywhere. This project describes the integration of MeasureNet into an experiment isolating the fluorescent protein phycocyanin. A dual-beam colorimeter probe is used to monitor the change in fluorescence upon denaturation of phycocyanin.

CHED 172

Crime scene science: Lab driven liberal arts and science class

Shawn G Garrett, of Chemistry, Minnesota State University Moorhead, Moorhead, Minnesota 56563, United States

Forensic science is a multidisciplinary field applying the basic sciences of physics, biology and especially chemistry to legal matters. Interest in crime scene investigations has led to many forensics high school courses and upper division courses for advanced college science students. However, at Minnesota State University Moorhead we have targeted college undergraduate students in offering a course in crime scene science. This laboratory driven class requires students to conduct forensic evidence analyses while learning the underlying science. This course is for non-science majors and assumes limited science and math backgrounds. All laboratories are presented as unsolved crimes; the labs activities include physical, microscopic and chemical analyses of hair and fiber, document analyses, fingerprint and impression development, DNA profiling and blood typing, glass and soil evidence analyses, identification of possible drug evidence and a final crime scene investigation involving evidence collection at a simulated crime scene, laboratory analysis of the evidence and a crime scene report. Basic science topics include measurements, use of proper standards and controls in experimental design, physical and chemical properties and changes, classes of chemical reactions, biological molecules and basic biochemistry. The course outline, more details on activities and resources, and how the basic science and forensic science have been combined to fulfill science transfer requirements will be presented. Initial student reactions will be shared, along with ideas for future course modifications and assessments.

CHED 173

Project iPad: Integrating iPads into organic chemistry

G. Robert Shelton, of Chemistry, Austin Peay State University, Clarksville, TN 37044, United States

This project aims to advance and promote general conceptual understanding in organic chemistry using different methods aided by iPads and Apps. Preliminary ideas are currently being field-tested by the PI's this academic year. Some units are a self guided exploration of a topic, while others are a larger guided inquiry where small group results are shared instantaneously with the classroom. Each chapter or unit within a semester of organic chemistry will ultimately have either a small group and/or classroom intervention centered around the iPad. The introduction of Apple's iPad and its ability to sustain and promote student inquiry and active learning will be discussed.

CHED 174

Fostering an induction into authentic research in the freshman/sophomore sequence

Matthew L Miller1,, David P Cartrette1, Kenneth Emo2.  (1) Department of Chemistry & Biochemistry, South Dakota State University, Brookings, South Dakota 57007, United States  (2) Departmen of Education, University of Minnesota-Morris, Morris, Minnesota 56267, United States

This two-year NSF funded (1044419) project created a model of laboratory instruction with the goal of increasing student interest in early involvement in research within the department of chemistry and biochemistry. The primary methods to create interest included using advanced instrumentation, inquiry methods, and collaboration. The implementation of this plan was unique in that students from two different chemistry laboratory courses (first- and second-year) were enrolled simultaneously in the same laboratory period. Activities were implemented requiring students from two different courses to work collaboratively toward answering a specific question. We will present how selected activities were integrated across both courses. Data were collected via surveys, observations, and a critical thinking examination (NSF CCLI) and analyzed to identify changes in student interest in research. We will present initial findings from the data to assess the role played by this model of instruction on increased research interest.

CHED 175

2012 ACS Global Innovation Grant Award: Computational Chemistry Teaching and Research Laboratory at Kenyatta University, Nairobi, Kenya

Lewis Whitehead1,, Heather Burks1, Brigitta Tadmor2, Nina Dudnik3, Evans Ogwagwa Changamu4.  (1) Global Discovery Chemistry, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139, United States  (2) Education, Diversity & Inclusion, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139, United States  (3) Seeding Labs, Boston, Massachusetts, United States  (4) Department of Chemistry, Kenyatta University, Nairobi, Kenya

At the 2012 spring ACS in San Diego the International Activities Committee announced the approval of a plan to award Global Innovation Grants to ACS technical divisions. We have been awarded the first Global Innovation Grant and present a progress report on our activities.

CHED 176

Augmenting in-lab demonstration with QR codes for smartphones

David Collins,, Timothy Lee.Department of Chemistry, SUNY Cortland, Cortland, NY 13045, United States

Surveys and anecdotal evidence suggest that smartphone usage among college students approaches 75%; implementing this technology into the instructional laboratory can leverage much of the benefits (on-demand information and tools) with lesser impact from the distractions they present. We present a set of QR codes which can be incorporated into handouts or lab manuals. These QR codes provide students with immediate access via smartphone app to short demonstration videos illustrating common general chemistry laboratory techniques.

CHED 177

Early instruction in NMR through improved coordination of laboratory and lecture topics in introductory Organic Chemistry

William E. Brenzovich Jr.,, Vernon Miller, W. Gary Hollis Jr..Department of Chemistry, Roanoke College, Salem, VA 24153, United States

With access to a 400 MHz NMR spectrometer with an autosampler, Roanoke College has been actively pursuing opportunities to further integrate the use of NMR spectroscopy in the introductory organic lab. We strongly believe that NMR should be introduced early in the lab program to maximize hands-on experience, but have found that students lack the required comprehension of organic structure to fully understand the technique in the early experiments . To realize our goals, we have recently explored and implemented several models to better integrate the teaching of NMR concepts in lab and lecture to allow for early instructional use of NMR in the organic lab, including earlier instruction on NMR concepts in lecture and a less rigorous use of NMR in early lab experiments. We will present an overview of the recent modifications made to the organic curriculum, and assess future directions for curricular development.

CHED 178

Institute for Accessible Science: Increasing laboratory independence for students with disabilities

Greg J. Williams1,, Bradley S. Duerstock1,2, Susan M. Mendrysa3, Lisa M Hilliard4, Wilella Burgess4, Loran Carleton Parker4.  (1) Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States  (2) School of Industrial Engineering, Purdue University, West Lafayette, Indiana 47907, United States  (3) Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States  (4) Discovery Learning Research Center, Purdue University, West Lafayette, Indiana 47907, United States

Persons with disabilities are under-represented both in STEM degrees and careers. Many programs have been established to increase the number of students with disabilities (SWDs) obtaining STEM degrees on the assumption that this would translate into their greater representation in the STEM workforce. However, the techniques and tools which enable them to complete a degree are not necessarily transferrable to the workplace. For instance, in chemistry lab courses students who are visually impaired rely on lab partners to conduct most of the experimental work.

The mission of the Institute for Accessible Science (IAS) at Purdue University is to develop and disseminate methods and technologies which enable SWDs to function more independently in university laboratories and beyond. This poster will describe some of IAS's ongoing projects and present case studies of two students with visual impairments whom the IAS assisted to develop solutions to barriers they encountered in labs.

CHED 179

Demonstration of chemical and physical principles through group construction of side by side freshwater and saltwater barometers

Richard W Gregor, of Chemistry, Rollins College, Winter Park, FL 32789, United States

An engaging re-creation of the 17th Century work of Torricelli and von Guericke, where students use a four story parking garage to build a water barometer from simple materials, is described. A novel aspect of the experiment is the simultaneous erection of a saturated sodium chloride barometer. The experiment introduces the following topics: pressure, density, solubility, boiling point, vacuum, vapor pressure, Dalton's, and Henry's Laws. The 10.4 m height of the water barometer offers a more easily visualized comparison to the 8.8 m for the saltwater barometer, than to either a mercury barometer or values from a weather service. This offers immunity from the difficult systematic corrections which would otherwise make comparisons frustrating, especially for novices. The experiment is suitable for students from high school through advanced college level, depending on the level of sophistication used in analysis. As part of the experience, we create a video documenting the activity.

CHED 180

Threading flavones through the undergraduate chemistry laboratory curriculum

David M Collard,, James C. Morris, David L. Jenson, Mary E. Peek, Stefan A. France.School of Chemistry & Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States

A curriculum “thread” in which students revisit aspects of a particular topic throughout the laboratory sequence over the four-year bachelor degree curriculum blurs the boundaries between traditional “divisional” laboratories and provides opportunities for inquiry-based activities and research-based learning. In the “Threading Flavones” project (supported by NSF award DUE 1044034) we are developing experiments in which students prepare a library of compounds and characterize their structure, chemical properties and biological activity in a series of exercises spread across organic, analytical, physical and biochemistry laboratory classes. The project is designed to better integrate learning and create the context, relevance and redundancy needed to promote student-focused learning goals such as retention of key concepts throughout the curriculum, critical thinking, development of laboratory and technical writing skills, and collaborative problem solving. The project includes faculty workshops to promote collaborative curriculum development and adoption.

CHED 181

Medicinal chemistry research at Texas Tech University Health Sciences Center School of Pharmacy

Teresa Carlisle, Paul C Trippier, of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas 79106, United States

The Department of Pharmaceutical Sciences at Texas Tech University Health Sciences Center (TTUHSC) School of Pharmacy in Amarillo is establishing a medicinal chemistry research concentration. The department seeks to build on internationally renowned researchers in cancer biology and pharmacology of the blood brain barrier.

Research area concentrations are in the design and evaluation of compounds that demonstrate activity to combat cancer and explore the tumor microenvironment, potential therapeutics for central nervous system diseases, and chemical neuroscience probes.

The acquisition of a new NMR spectrometer will complement the departments HPLC, and LCMS core equipment, providing excellent facilities for synthetic medicinal chemistry. Newly refurbished laboratories are currently under construction with state of the art chemical and biological hoods.

We are currently accepting applications for our graduate program in pharmaceutical sciences. Interested students are encouraged to explore the program website: For additional information and questions about admissions email

CHED 182

Designing quantum dot solids for next-generation solar cells

Matt Law, of Chemistry, University of California, Irvine, Irvine, CA 92697-2025, United States

In this talk, I will provide an overview of ongoing efforts to design lead salt quantum dot (QD) thin film absorbers for next-generation QD photovoltaics, with particular emphasis on recent accomplishments and future opportunities in this area. Basic requirements for QD absorber layers include efficient light absorption, charge separation, charge transport, and long-term stability. I will first discuss several methods used to make conductive QD films by solution deposition and ligand exchange. Studies of carrier mobility as a function of basic film parameters such as inter-QD spacing, QD size, and QD size distribution have led to a better understanding of charge transport within highly disordered QD films. Efforts to improve carrier mobility by enhancing inter-dot electronic coupling, passivating surface states, and implementing rudimentary doping will be highlighted. Engineering the inter-QD matrix to produce QD/inorganic or QD/organic nanocomposites is introduced as a promising way to optimize coupling, remove surface states, and achieve long-term environmental stability for high-performance, robust QD films. To obtain large photocurrent from QD solar cells, it is critical to increase the minority carrier diffusion length to rival the optical absorption length, possibly by harnessing band-like transport through extended electronic states. The relative roles of superlattice order, energy disorder, and surface states in this regard will be summarized. The talk will conclude with comments on the prospects for controlled doping and rational p-n junction formation in QD systems.

CHED 183

From scientific discovery to commercial success: How great innovators cross this chasm and achieve a triple play

Kirk Froggatt, Leadership Institute, University of Minnesota, Minneapolis, MN 55455, United States

Scientific expertise is absolutely necessary, but not sufficient to excel as an innovator and cross the chasm from lab research to commercial success. In this session we will explore several principles, tools and practices to supplement your technical expertise and help you navigate the “three C's” of innovation: the broader context (the innovation ecosystem), the capability required for a commercially viable solution (the business model), and the collaboration practices necessary to execute the business model successfully. These principles and practices will be illustrated through case studies where scientific R and D is translated into innovative solutions with “triple play” results: a win for the customer, win for the business, and a win for the environment.

CHED 184

Energy and the individual: The artificial leaf

Daniel G. Nocera, of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, United States

This talk will focus on recent advances in developing sustainable and affordable energy sources for every individual. An "artificial leaf" that is capable of mimicking photosynthesis has been developed. In the the presence of sunlight, this leaf splits H2O into H2 and O2, which can be harnessed by a fuel cell for energy production. Inexpensive to manufacture and produced from Earth-abundant materials, this artificial leaf has great potential for commercial applications. The transformation of this chemistry to a viable business venture will illustrate the unique challenges that solar energy technologies face in the marketplace.

CHED 185

Providing international and multicultural perspectives for the education of undergraduate science students

Morton Z. Hoffman, of Chemistry, Boston University, Boston, MA 02215, United States

How can science undergraduates gain a global perspective? Although they can enroll directly in a university in another country, there are a number of serious deterrents, such as language, prerequisites, and calendar. A study abroad experience is another option, but science students (especially chemistry majors and pre-medical concentrators) have historically been extremely underrepresented; they do not believe it can be done within their seemingly inflexible programs of study, the administrative obstacles appear daunting, and the faculty are not necessarily supportive of the idea. An alternative is to have the science courses taught in English at a foreign site. The Boston University science study abroad programs in Dresden, Germany (since Fall 2006), Grenoble, France (since Fall 2009), and Madrid, Spain (since Fall 2012) are models that afford a student the opportunity to study abroad for a full semester as a science major (e.g., chemistry, biochemistry, biology, pre-health professions, etc.) while avoiding the common obstacles.

CHED 186

Overview of Macau's tertiary chemical education

Pong Kau Yuen1,, Diana, Cheng Man Lau2.  (1) Faculty of Science and Technology, University of Macau, Macau  (2) Faculty of Management and Administration, Macau University of Science and Technology, Macau

Education and chemistry are important subject areas which have strong impacts on our life and our future. Chemical education plays a critical role in fostering students' science literacy and promoting the sustainable society. Currently Macau is undergoing a series of education reforms. Nevertheless, the Macau's chemical education is rarely discussed and researched. The purpose of this paper is to review the development of chemical education at the tertiary level in Macau, analyze the characteristics of chemistry curriculum and explore the possible reforms in chemical education.

CHED 187

Establishing a cultural network through chemical education

Patricia Morales Bueno1,, Carmen Valdez Gauthier2,  (1) Department of Sciences - Chemistry Section, Pontifical Catholic University of Peru, Lima, Lima, Peru  (2) Department of Chemistry, Florida Southern College, Lakeland, Florida 33813, United States

This paper describes the experiences of two chemical educators who originally met as undergraduate students in the chemistry program at the Pontifical Catholic University of Peru (PCUP) in the 1970s and now teach college level chemistry -one in Peru and one in the United States. The characteristics, strengths and weaknesses of teaching chemistry in Peru and in the United States will be compared and discussed including the potential influence of cultural differences on teaching effectiveness. Collaborative efforts to involve both Peruvian and American students in problem solving exercises using social networking sites will be discussed. The importance of e-global experiences for students who are not able to participate in study abroad programs will also be discussed.

CHED 188

Participation of foreign-educated faculty in undergraduate chemistry education

Santiago Sandi-Urena,, Matthew Sestilio, Todd Gatlin, Adrian Villalta-Cerdas.Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States

Chemistry faculty demographics have changed considerably over the past three decades. Although minorities and women continue to be underrepresented in faculty positions, the proportion of foreign-born professors has increased substantially. The diversity that this brings is celebrated and in terms of research it pays dividends. It also gives students access to a global perspective that may be beneficial in their professional practice. However, in most cases these professors have completed their K-16 education in educational systems substantially different from that in the US and the influence of this unfamiliarity has seldom been discussed. Moreover, chemistry assistant professors receive little to no instructional training before immersing in undergraduate education. There is very little work done to investigate the consequences that unfamiliarity with the system, lack of training, conflict of expectations, cultural and communication factors and other related aspects may have on foreign-born professors and undergraduate students' experiences. This presentation intends to present some data and start a discussion around this topic.

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Multicultural perspectives on chemical design

Gabriela A Szteinberg1,, Steven Cullipher1, Courtney Ngai1, Hannah Sevian1, Heilen Arce2.  (1) Chemistry Department, University of Massachusetts Boston, Boston, Massachusetts 02125, United States  (2) Chemistry Department, University of Costa Rica, San Pedro, San Jose, Costa Rica

There has been a recent surge of interest in developing learning progressions of central ideas that can serve as curriculum models and assessment frameworks in educational settings. The analysis, synthesis, and transformation of chemical substances have many benefits for modern societies. However, social, political, economic, and environmental costs and risks need to be taken into account when making decisions involving the application of chemical design. To explore the role that culture and context may play in individuals' thinking about chemical design, we have expanded our study of a learning progression in chemical design with students in an urban university by including students at a university in Costa Rica. We will present results based on similarities and differences students from the U.S. and Costa Rica demonstrate when prompted to think and reason about chemical structure and property relationships, and the benefits, costs, and risks associated with designing chemical processes.

CHED 190

Who teaches matters: OXIDE's role in advancing multicultural perspectives in research-active chemistry departments

Shannon Watt,, Rigoberto Hernandez.School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400, United States

The persistence of undergraduate and graduate students in chemical careers is influenced daily by the faculty role models who shape their educational and research environments. While the demographics of the U.S. and student populations are evolving at ever-accelerating rates, faculty diversity and the academic culture experienced by individuals from under-represented groups change at a significantly slower pace. In order to fully utilize our nation's intellectual capacity, it is critical to establish faculty demographics and educational environments that not only reflect but also embrace the composition and multi-cultural realities of our society in terms of gender, race-ethnicity, sexual orientation, and disability status.

The Open Chemistry Collaborative in Diversity Equity (OXIDE) aims to reduce inequities that have historically led to disproportionate diversity representation on academic faculties by leading an ongoing national conversation between chairs of leading doctoral-granting chemistry departments, representatives from diversity communities, and social scientists with diversity-related expertise. This presentation will discuss OXIDE's activities, which are driven by:

CHED 191

Introduction to POGIL and The POGIL Project

Rick Moog, of Chemistry, Franklin and Marshall College, Lancaster, PA 17604, United States

POGIL (Process Oriented Guided Inquiry Learning) is a student-centered, group learning strategy for teaching chemistry (and other sciences) at all levels. The POGIL Project ( is an organization focused on promoting the use of these types of approaches at both the college and high school levels across the country. This presentation will introduce the fundamental principles of POGIL, and will describe the professional development opportunities and curricular materials available from The POGIL Project.

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Process oriented guided inquiry learning (POGIL) in general chemistry: The thrill of victory and the agony of defeat

Gary D DeBoer, of Chemistry and Physics, LeTourneau University, Longview, TX 75602, United States

Performance and attitudinal outcome measures of the use of POGIL in the general chemistry classroom are quite varied depending on class size, and student preparation. Apparent increases in retention were observed when using POGIL versus traditional lecture in two comparative smaller second semester classes, though class size and student skill levels were also factors. Attitudinal responses to a non-traditional classroom approach were positive for the small second semester class. In larger, first semester classes, performance outcome measures were comparable for POGIL and lecture; however, attitudinal measures to a POGIL approach were negative. As a result of these findings, a hybrid approach combining lecture and POGIL activities is now used in both semesters of general chemistry, with a greater lecture component in the first semester. Performance outcomes measures for the hybrid approach appear to be consistent with previous years, and attitudinal responses have been more positive than either a lecture or a POGIL approach. This presentation will be of interest to any student, faculty, or administrator interested in classroom pedagogy and retention at the secondary or tertiary level. Go to <> for more information on the speaker.

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POGIL in introductory organic chemistry: Using electron energies to build understanding of molecular reactivity

R Daniel Libby,, Moravian College, Bethlehem, PA 18018, United States

Undergraduate chemistry students learn about electron energies in the context of atomic structure. However, they next consider electron energies when they deal with quantum mechanics in physical chemistry. All other energy considerations deal with overall changes in bulk materials (ΔH or ΔG) for reactions or phase changes. In organic chemistry students are introduced to “stabilities,” “reactivities” or “electrons availability” in reactions with no connection to energies of structures. It is not surprising that they develop little sense of how energies of structures control reactivity. My POGIL approach to intro organic starts with the atomic energy levels, which are familiar from general chemistry, and helps students use acid pKa values to judge the relative energies of electrons in molecules. Students can then readily identify the highest energy electrons in a reaction system and use them to predict sites of reaction and either relative rates or relative equilibrium constants for reactions.

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POGIL and science writing in an interdisciplinary course on climate change

Charity Lovitt, of Chemistry, Seattle University, Seattle, WA 98122, United States

An interdisciplinary course on the chemistry and controversy of climate change was developed for non-science majors. Students entered the course with a variety of backgrounds in chemistry which made it difficult to pace material. The POGIL method proved to be a useful tool for this class because strong students in each group could coach weak students, allowing the instructor to focus on correcting misconceptions in the class. Students used the POGIL method of Exploration, Model, Application to understand chemistry topics of spectroscopy, Lewis structures, and stoichiometry while also using the method to interpret complex graphs on climate change research. Students learned about the scientific method by exploring data, creating models, and applying their model to correct misconceptions in climate change. The culminating project was the creation of a scientific document to train employees at the local public science center on misconceptions in climate science.

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Pilot POGIL (Process Oriented Guided Inquiry Learning) in CHE 115 General Chemistry I in a HBCU institution

George H Armstrong,, Tougaloo College, Tougaloo, MS 39174, United States


Two courses of CHE 115 General Chemistry I were taught simultaneously. One course was taught using the traditional lecture method and the other course was taught using the POGIL method. The courses were compared to determine the effectiveness of POGIL in General Chemistry I. Assessment tools were the American Chemical Society (ACS) “Toledo Chemistry Placement Examination” (pre-test), the ACT math scores of entering Fresh Persons, and the ACS test for General Chemistry I (post-test). Relative performances in General Chemistry I, percent of students passing with a grade of C in CHE 115, and comparative success of students in General Chemistry II were used to determine the success of POGIL. Presently, the pilot has run for three semesters. While the number of students for each course was too small for statistical analysis, the following trends seem to be apparent: 1) The success of the POGIL students (pass with a grade of C or higher) is better, and 2) the POGIL students do as well or better in General Chemistry II, which is taught with the traditional lecture method.

CHED 196

Developing a robust POGIL model to teach the thermodynamics of biochemical reactions to nursing students

Diane M. Dean,, Ellen Anderson.Department of Chemistry, University of Saint Joseph, West Hartford, Connecticut 06117, United States

The inquiry approach to science education has been recommended by the National Science Foundation (NSF) and the American Association for the Advancement of Science (AAAS) for several decades. Process-oriented Guided-inquiry Learning (POGIL) is a pedagogy that was developed to teach introductory chemistry as a response to the recognized need by NSF and AAAS. It was expanded to biochemistry for major courses in the last 5 years. Nursing and allied health students constitute a population that has not benefitted from this pedagogy revolution. Making foundational coursework relevant to the student through inquiry exercises is critical for retention. The objectives taught include: describing the thermodynamic reasons for the irreversible reactions in glycolysis. The model described in this work visually explains the thermodynamic changes that occur during the ten reactions in glycolysis. Improved retention will enhance the student's ability to transfer this foundational knowledge to later coursework and professional practice.

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Facilitating chemistry using POGIL and student responders

Susanne M Lewis, of Natural and Physical Science, Olivet College, Olivet, MI 49076, United States

In the author's second year of teaching in a tenure-track position, organic chemistry lecture was converted to Process Oriented Guided Inquiry Learning (POGIL) using the published materials for this content area. The rational for changing from traditional lecture to POGIL will be discussed as well as accounts of successes, frustrations, and modifications, and how student responders (“clickers”) are used to manage the class material.

CHED 198

Computer simulations and guided-inquiry tutorials: The Next Generation Project

Thomas J. Greenbowe1,, John I. Gelder2, Michael R. Abraham3.  (1) Department of Chemistry, Iowa State University, Ames, IA 50011, United States  (2) Department of Chemistry, Oklahoma State University, Stillwater, OK 74078, United States  (3) Department of Chemistry, The University of Oklahoma, Norman, OK 73019, United States

Computer simulations, if properly integrated into an instructional module, can potentially provide teachers with a powerful teaching tool. The Next Generation Computer Simulation Project integrates the use of computer simulations with guided-inquiry tutorials. "Before", "During", and "After" class activities and tutorials are being used to help teachers identify topics students find difficult and can help students gain a better understanding of concepts. One purpose of the tutorials is to help students develop a model of a system. A model can be used to help students explain and predict behavior of matter. Using a learning cycle, students can improve their model and understanding of the chemical concept. Computer simulations can help students structure and to carry out an experimental design to answer a question. Students can work in groups to quickly collect, analyze, and graph data. The pooled data and graphs can help students see a pattern. Instructors can introduce the concept. Students can do a problem incorporating a higher-level application of the model. Thus, the learning cycle plays a central role in uniting a computer simulation with a specially designed tutorial. Computer simulations can also include visualizations of the behavior of matter at the particulate level. A beta version of an electrochemistry computer simulation will be presented along with an example of how a computer simulation accompanied by a POGIL-like tutorial can help students gain a better understanding of electrochemistry.

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AP Chemistry 2013 and Beyond incorporates a guided-inquiry approach in the classroom and in the laboratory

Marian L. DeWane2,, Thomas J. Greenbowe1.  (1) Department of Chemistry, Iowa State University, Ames, IA 50011, United States  (2) Department of Extension, University of California - Irvine, Irvine, CA 92697, United States

The AP Program has spent several years reviewing and redesigning the AP Chemistry Curriculum. This new course focuses on student understanding of chemistry while simultaneously developing students' analytical reasoning and inquiry-based skills. AP inquiry instruction incorporates any teaching method designed to encourage students to construct and to discover knowledge with an understanding of how scientists study the natural world. AP lab investigations align with best practices described in America's Lab Report, which promotes a student involvement, inquiry-based design. The teacher edition of the new AP Chemistry lab manual and a special Curriculum Module on implementing Guided-Inquiry in the Classroom will be available in 2013. This presentation will outline the content of these two new resources. Similarities and differences between the AP Chemistry approach and the POGIL/SWH approaches will be discussed.

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Helping students succeed in organic chemistry with peer-evaluated presentations, study baskets, and social media

Ekaterina N. Kadnikova, of Chemistry, University of Missouri - Kansas City, Kansas City, Missouri 64110, United States

I will share my experiences with “Elementary Organic Chemistry,” a one-semester comprehensive course designed for students in the six-year BA/MD program. One of my goals is to teach future doctors to understand and appreciate the fundamental role of organic chemistry in modern medicine. Thus, “Molecules-in-Medicine” unit provides the students with an overview of pharmaceutical and medicinal chemistry and their role in drug development. It culminates in student presentations on the organic chemistry of small-molecule drugs. This unit allows students to discover for themselves how far they have grown in this course. Peer-reviewing each other's presentations is another unique experience. Success of this endeavor ignited my interest in further innovations. “Study baskets” filled with workbooks are now available for check-out at the library and at the dorms. Finally, using social media as a teaching tool proved to be a great success. Our Facebook discussion group has been very popular with students.

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Flipped organic chemistry classroom at a small comprehensive college: Organic chemistry upside down

Jessica M Fautch, of Physical Sciences, York College of Pennsylvania, York, Pennsylvania 17403, United States

The “flipped” classroom is an approach to teaching that involves active learning while increasing student responsibility and improving comprehension. The flipped, or inverted, model takes traditional lecture from in-class to outside the classroom in the form of online lectures or tutorials. Work traditionally completed as homework is carried out through engaging group activities and instructor-guided problems during class. Techniques used to flip an undergraduate organic chemistry course, including “vodcast” lectures, electronic homework, and “warm-ups”, are discussed. In-class discussion and problem-solving are also investigated as means to facilitate deeper learning of organic chemistry. Student learning outcomes in a flipped organic chemistry course are predicted to include efficient problem solving skills and the ability to verbally explain the material to one's peers. When an inverted classroom model is applied to organic chemistry, we anticipate increased comprehension and retention of the material, as well as improved performance on summative assessments (exams).

CHED 202

Reducing lecture and increasing impact in an organic I course: Design and assessment

Kimberly Cossey, of Chemistry and Physics, Georgia College & State University, Milledgeville, GA 31061, United States

Imagine an organic chemistry classroom where instead of listening to a lecture, students are leading a discussion based off their readings. Imagine students studying, but instead of making flashcards and lists, they are engaging in complex problems and devising strategies to complete them. This vision was used to design my current organic I course. Using backward course design, an organic I course has been restructured so that rather than lecturing over every concept, the professor helps students to prioritize concepts, provides problem solving strategies, and fills-in key details as needed. Active learning strategies (adapted from POGIL and PBL methods) have been used to engage students in critical thinking and application tasks. Assessment will focus on traditional outcomes (e.g. solving synthetic and mechanistic problems), as well as secondary outcomes, such as critical reading. This talk will focus on the design and initial assessment (1 class section) of the course.

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Pedagogical focus for training peer leaders to improve comprehension in organic chemistry

Connie Gabel, of Chemistry, Metropolitan State University of Denver, Denver, Colorado 80217, United States

Peer leaders receive instruction on how to lead group study sessions for organic chemistry using a constructivist framework. Dynamic interactions between students as well as with the peer leader encourage participation among the students. Peer leaders are selected based on their command of organic chemistry in addition to their ability to interact well with peers in a group study setting. The peer leaders are taught the importance of using neural scaffolding to help control student frustration when learning organic chemistry concepts. Another key technique incorporated in training peer leaders is learning to initiate the construction of knowledge using the Socratic method. Working problems on the board and in small groups helps students to solve problems beyond the zone of proximal development with the assistance of a more capable peer. These methods facilitate the creation of a scholarly learning community for improving comprehension in organic chemistry. Results indicate a significant difference.

CHED 204

Indicators of success in organic chemistry

Kevin M. Bucholtz1,, Mark F. Owens2.  (1) Department of Chemistry, Mercer University, Macon, GA 31204, United States  (2) Department of Economics and Finance, Middle Tennessee State University, Murfreesboro, TN 37132, United States

A student's success in organic chemistry is a complex and multi-faceted problem that has many variables for whether a student succeeds or subscribes to the “weed out” reputation of the course. The course is challenging for many students because of the difficulty of the material and the traditionally qualitative foundation of the curriculum. A variety of statistical methods have been used to analyze six years of data from a single institution to better understand these variables. The data identifies indicators of student success from the organic chemistry course, the chemistry curriculum as a whole and pre-college performance. With this data, it has provided the foundation to enhance and improve pedagogical approaches in organic chemistry.

CHED 205

Engaging students in publishing on the internet early in their careers

Antony J. Williams1,, Valery Tkachenko1, Colin Batchelor2, David Sharpe2, Jon Steele2.  (1) Cheminformatics, Royal Society of Chemistry, Wake Forest, NC 27587, United States  (2) Cheminformatics, Royal Society of Chemistry, Cambridge, United Kingdom

As a result of the advent of internet technologies supporting participation on the internet via blogs, wikis and other social networking approaches, chemists now have an opportunity to contribute to the growing chemistry content on the web. As scientists an important skill to develop is the ability to succinctly report in a published format the details of scientific experimentation. The Royal Society of Chemistry provides a number of online systems to share chemistry data, the most well known of these being the ChemSpider database. In parallel the ChemSpider SyntheticPages (CSSP) platform is an online publishing platform for scientists, and especially students, to publish the details of chemical syntheses that they have performed. Using the rich capabilities of internet platforms, including the ability to display interactive spectral data and movies, CSSP is an ideal environment for students to publish their work, especially syntheses that might not support mainstream publication.

CHED 206

Evaluation of photo-induced crosslinking of thymine polymers using FT-IR and chemometric analysis

Kris McDonough1,, Rebecca Koelln1, Kiara Dupuy1, Jennett Chenevert1, Getey Anwar1, Monica Khun1, Caroline Coughlin1, Deepa Kumarjiguda1, Santiago Bortolato2, Debora Martino2, Rich Gurney1.  (1) Department of Chemistry and Physics, Simmons College, Boston, MA 02115, United States  (2) Instituto de Desarrollo Tecnológico para la Industria Química (INTEC) (UNL -CONICET), Santa Fe, Santa Fe S3000GLN, Argentina

In recent years there has been a great interest in the design and construction of micro and nanostructures having functional responses to external stimulus, such as pH, temperature and light, especially for use as microsensors and controlled release systems.

Copolymers containing thymine residues 4-vinylbenzyl thymine (VBT) and ionic styrene derivative 4-vinylbenzyl triethyl ammonium chloride (VBA) of varying compositions were evaluated. Comparable to naturally-occuring DNA chains, UV irradiation induces the formation of cyclobutane dimers between neighboring thymine residues, resulting in three-dimensional crosslinking of copolymer chains. The photo-dimerization kinetics for the copolymers have been investigated using grazing-angle specular-reflectance Fourier-Transform infrared spectroscopy, complemented by Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) methods. The study allows the sequential estimation of the contribution to the total signal due to different species, which can be used to calculate the crosslinking rate.

CHED 207

Impact of alkyl group on aggregation and fluorescence quenching for a homologous series of squaraines targeted for photovoltaic devices

Victor M Murcia1,, Susan D Spencer2,3, Bi Zhu1, Brandon Cona1, Patrick Heaphy1, Jeremy A Cody1, Christopher J Collison1,2,3.  (1) School of Chemistry and Materials Science, Rochester Institute of Technology, Rochester, New York 14623, United States  (2) Microsystems Engineering, Rochester Institute of Technology, Rochester, New York 14623, United States  (3) NanoPower Research Laboratory, Rochester Institute of Technology, Rochester, New York 14623, United States

Squaraines offer a small molecule alternative for spectral harvesting in the near infrared region of the solar spectrum, where there exists a large supply of photon density that can be leveraged in tandem organic photovoltaic devices. Squaraine molecules exhibit panchromaticity, high extinction coefficients and a high stability to oxidation, and therefore have stimulated recent high levels of investigation. We study a series of squaraines synthesized in our group, where there are some molecular packing anomalies in the solid state, which we propose will impact the efficiency of organic solar cells. We demonstrate that the packing geometry of di-hydroxy-anilinic squaraines may depend predominantly upon the branching at the second carbon on the alkyl sidechains. We provide supporting evidence along with the power conversion efficiency data, which points towards new strategies for improving device efficiencies.

CHED 208

Chemical treatment of wastewater from a leather tanning facility

Jessica S George,, Heather J Shipley.Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, United States

The process of leather tanning produces harmful pollutants. In order to meet regulatory standards, this study explored chemical treatment methods to successfully and efficiently reduce the concentrations of harmful pollutants in the wastewater. Multiple wastewater streams representative of various stages in the tanning and wastewater treatment processes were initially characterized and subsequently treated through means of chemical coagulation and adsorption. Through a series of jar test experiments, use of multiple industry-grade polymers as chemical coagulants greatly reduced chromium concentrations and turbidity levels. The wastewater streams were also subjected to adsorption experiments to see chromium and nitrogen removal efficiency of metal oxide nanoparticles and activated carbon at varying concentrations over a 24hr period. Though poor adsorption of chromium occurred by both the nanoparticles and activated carbon, the activated carbon was successful in reducing nitrogen levels by over 90%. Having tested different methods for wastewater treatment, the use of polymers as coagulants was deemed the most successful at removal of chromium and improvement in clarity.

CHED 209

How much caffeine is in your cup? Quantifying caffeine for a local coffeeshop

Katie M. Fredo,, Kimberly Cossey.Department of Chemistry, Physics, and Astronomy, Georgia College and State University, Milledgeville, Georgia 31061, United States

The primary goal of this research is to determine the amount of caffeine in coffee from a local coffee shop in Milledgeville, Georgia. Blackbird Coffee coffee shop has requested information on the caffeine content in their products to report to their consumers. Caffeine is a stimulant and is most commonly consumed through coffees and teas. Even though caffeine content can vary widely based on various factors (the brewing methods used, the acidity of the coffee, etc.), consumers want to know how much caffeine they consume. In this research, liquid-liquid extraction was used to separate the caffeine from the other contents found in coffee. The extracted caffeine was characterized via 1H-NMR spectroscopy to confirm that caffeine was extracted and to analyze the purity of the caffeine. The mass of the recovered caffeine was recorded and compared to caffeine from commercial products.

CHED 210

Motivating students to persist in general chemistry: A potential solution

Amanda F Cook1,, Lisa C Duffin2, Martha M Day1.  (1) Department of SKyTeach, Western Kentucky University, Bowling Green, Ky 42101, United States  (2) Department of Psychology, Western Kentucky University, Bowling Green, Ky 42101, United States

The purpose of this study was to examine the self-efficacy beliefs and attitudes towards general chemistry in a sample of (n = 1,126) first-time, first-year freshmen from a large comprehensive university in the Mid-South. The following research questions were examined: 1) how well do self-efficacy beliefs for general chemistry and attitudes toward chemistry predict intentions to take future chemistry courses?, 2) which is the best predictor of intentions; self efficacy for general chemistry or attitude toward chemistry?, and 3) If other known factors that influence intentions (i.e., past experiences, past performances, and choice of major) were controlled, is self-efficacy for general chemistry and attitude toward chemistry still able to predict a large amount of the variance in intentions to take future chemistry courses? Findings from the regression analyses with statistical significance will be presented and implications for science educators and STEM administrators will be discussed.

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Pre-service teacher impacts from working in a peer tutoring center

Mary C Martin1,, Janice Hall Tomasik1, Debra Linton2, Anthony Feig3.  (1) Department of Chemistry, Central Michigan University, Mount Pleasant, Michigan 48858, United States  (2) Department of Biology, Central Michigan University, Mount Pleasant, Michigan 48858, United States  (3) Department of Geography, Central Michigan University, Mount Pleasant, Michigan 48858, United States

The Peer Assistance Center (PAC) is a chemistry tutoring center open to all students in 100-level chemistry courses. The tutors hired for the PAC are pre-service teachers who have completed a training session taught by the PAC advisors. Qualitative data collected by an interview of four of the PAC tutors will be discussed. This interview revealed parallels between the concepts tutors help students with and the content for Teacher Preparation and the Michigan Teacher Training Certification. Additionally, PAC tutors report the center helps them practice different teaching methods and build a rapport between students and faculty.

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Rewards and challenges of an academic career in predominately undergraduate teaching institutions: A fifteen year, three-university retrospective

Donna K Howell, of Natural and Physical Sciences, Park University, Parkville, MO 64152, United States

The presenter, a tenured faculty member at Park University in the Department of Natural and Physical Sciences currently serving as department chair, will reflect over the course of her career spanning 3 very different primarily undergraduate institutions -- public and private, secular and non-secular, strong research focus and predominantly teaching focus. Comparisons and contrasts between the three institutions will be drawn in order to give individuals considering an academic in this venue a full understanding of the demands of the field.

CHED 213

Career advancement as adjunct faculty

Charity Lovitt, of Chemistry, Seattle University, Seattle, WA 98122, United States

Over 40% of college academic faculty in the US college system are non-tenure track faculty, many of whom are adjunct faculty on short-term contracts.It is expected that this number will increase. This paper will describe ways to obtain professional development while adjunct faculty. It lists strategies for dealing with rejection and uncertainty while pursuing an active career. It will discuss strategies for dealing with the two-body problem (two specialized professions, one couple). It is important to be flexible in career options, to keep learning new skills because it is never known when a job may open up that needs that expertise.

CHED 214

Maneuvering the path of academic fulfillment: The search, tenure, and promotion process

Joy J. Goto, of Chemistry, California State University, Fresno, Fresno, California 93740, United States

We often try to match our inner goals of academic success with the outer expectations of the search, tenure, and promotion process. In most cases, the path you take in your academic job search is a winding road that leads to a meeting point where one begins their tenure-track position as an assistant professor. I will describe the job search process and retention, tenure, and promotion (RTP) plan at a four-year public university with a M.S. research program. I can offer the perspective of one that has sanely managed the RTP process and come out on the other side both elated and satisfied with the journey. I will also add insight into what search committees seek in potential colleagues at the university-level. I hope to ease the process and relate my story in the hopes of making the road easier to traverse.

CHED 215

Effective practices in teaching and mentoring: How to teach better, save time, and have more fun

Penny J Beuning1,, Scott A Snyder2, Dave Z Besson3.  (1) Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, United States  (2) Department of Chemistry, Columbia University, New York, New York 10027, United States  (3) Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045, United States

Faculty members at research universities face many challenges in establishing themselves as effective teachers, researchers, and mentors. Early in faculty careers, precious time can be lost to reinventing the wheel in teaching and mentoring. Many new faculty tend to spend too much time on teaching duties and spend too little time on scholarly work (Felder 1998 Chem Eng Ed v32 p46), which can lead to feelings of isolation and dissatisfaction. New faculty in the physical sciences face particular challenges, as they often teach large lecture classes, which may also be required courses for non-majors. We are surveying Cottrell Scholars, who are a group of faculty identified for their commitment to integrating research and education, to identify effective practices in teaching and mentoring. This work will be made available to new faculty as a book and on-line to help new faculty teach better and enjoy the experience more.

CHED 216

Developing a research program at a community college

James Mendez, of Liberal Studies and Education, Sowela Technical Community College, Lake Charles, Louisiana 70616, United States

The prospect of establishing a research program at any level can be daunting; however, community colleges present a unique set of opportunities and challenges. After graduate school, the prospect of working in industry or two years in a lab as a postdoc were not appealing, leading me to apply for instructor positions. With absolutely no research, I did not plan to stay long at Sowela Technical Community college when I started two years ago. After a few months though, I realized that these students were just as interested in learning and research as any traditional 4-year student. The limiting factors for these students were the lack of faculty interested in research along with no infrastructure. Both local and state grants have improved our infrastructure and simultaneously encouraging further faculty involvement. While not easy, developing a research program at a community college can be rewarding for faculty as well as students.

CHED 217

More than teaching and research: Early career experiences at a teaching-intensive liberal arts college

An-Phong Le, of Chemistry and Physics, Florida Southern College, Lakeland, Florida 33801, United States

Florida Southern College is a regional liberal arts college affiliated with the United Methodist Church and is particularly focused on teaching and engaged learning. I will discuss my experiences as a second year faculty member in a young department which is, in many ways, in transition. I have been heavily involved in departmental and college-wide efforts to grow and support the natural sciences and to increase research activity. Particular mention of faculty duties outside those traditionally associated with teaching and research will be made, and I will offer additional perspectives from having already been involved with three faculty searches.

CHED 218

Life on the Hill: Early career experiences at Seton Hill University, a teaching oriented liberal arts university

Diana Hoover, of Natural and Health Sciences, Seton Hill University, Greensburg, PA 15342, United States

The “day in the life” of an assistant professor of chemistry at a liberal arts university with a strong teaching focus will be shared. Seton Hill University is a Catholic, liberal arts coeducational university with approximately 2000 students located near Pittsburgh, Pennsylvania. The teaching, scholarship, and service expectations at this type of university will be defined, with particular emphasis given to personal experiences in undergraduate research mentorship and teaching.

CHED 219

Adventures from the hunt, setting up camp, and forging a new trail: Postcards from the strange land of Academia

William A Alexander, of Chemistry, The University of Memphis, Memphis, TN 38152, United States

In this presentation, I will share perspectives gained while hunting for an academic position, and during my successful adventures interviewing at a variety of institutions ranging from small four-year PUIs to large research universities. Similarities and differences between the interview processes at the various institutions will be highlighted, and insightful opinions will be offered to aid job-seekers in their pursuits.

I will also report on my first-year experiences managing classroom instruction and establishing my research group at The University of Memphis, a learner-centered metropolitan research university which serves a diverse population of over 18,000 undergraduate and 4,000 graduate students. The Department of Chemistry at U of M currently consists of two dozen faculty, who serve over fifty graduate students (PhD and MS) and hundreds of undergraduates, graduating about two dozen chemistry majors per annum. I will delineate how my expectations coming into the position have shaped up with reality.

CHED 220

Sunshine and maple syrup: Early years for chemistry faculty at the University of Vermont

Rory Waterman, of Chemistry, University of Vermont, Burlignton, VT 05405, United States

With the smallest state allocation per capita in the country, UVM is a flagship state research university that operates very much like a private research-intensive university. Therefore, it is somewhat surprising that the institution has always had a small chemistry faculty (currently 11 tenure/tenure track), especially given the undergraduate teaching load of ~3500 students per year. Though stated effort distribution of 40:40:20 teaching to research to service might be skewed under these numbers, the department works to maintain relatively low teaching loads within contract-mandated stipulations. Despite (or perhaps because of) these factors, UVM chemistry ranked higher than “peer” institutions in many research productivity indicators (publications per year, etc.) in the most recent NRC rankings. Within those numbers a supportive, a collegial atmosphere has led to success for many junior faculty at UVM.

CHED 221

Strive and thrive in academic career: An example of early-career faculty in environmental engineering

Venkataramana Gadhamshetty, and Environmental Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States

The presentation provides an overview on the experience of early-career teaching faculty at Rensselaer Polytechnic Institute. The first half of the presentation will be geared on basic information about RPI- students, faculty, research facilities, and campus. The second half of the presentation will revolve around faculty's experiences (broadly defined) during his three years of stay at RPI. The presentation will include information on the demonstrated strategies to introduce research education to undergraduates during their early career.

CHED 222

Addressing global challenges in sustainability through catalysis

Melanie S. Sanford, of Chemistry, University of Michigan, Ann Arbor, MI 48109, United States

This talk will describe basic research efforts aimed at addressing global
challenges in sustainability via catalysis. These efforts are supported by the NSF
Center for Enabling New Technologies through Catalysis (CENTC). Topics will
include developing more energy efficient catalytic routes to fuels, commodity
chemicals, and fine chemicals as well as methods for the catalytic reduction of
carbon dioxide.

CHED 223

Systematic development of an artificial solar-fuel generation device

Nathan S. Lewis, of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, United States

Addressing the world's energy challenges will require cost-competitive, globally scalable technologies for fuel production that minimize impact on the environment. Despite decades of research focused on understanding and improving the efficiencies of natural photosynthesis, the energy conversion efficiencies of the most productive biofuel crops remain too low for mass industrialization of bioenergy. The Joint Center for Artificial Photosynthesis (JCAP) focuses on an alternative approach that aims to produce chemical fuels from sunlight, water, and carbon-dioxide using an engineered, non-biological device that is cost-effective, robust, and efficient. Research at JCAP involves the development of core technologies for artificial solar–fuels generation, including directed and combinatorial methods for the discovery of light-absorbing, semiconductor-based materials and water-splitting and carbon dioxide reducing catalysts, the design of ion-permeable, gas-separating membranes, and methods for efficiently integrating and assembling these components into fully functional prototypes. Recent discoveries in JCAP have led to significant advances towards commercially viable, solar-fuel producing systems.

CHED 224

Comparative study of undergraduate chemistry curricula and teaching in India and USA

Anil C Banerjee, of Chemistry, Columbus State University, Columbus, GA 31907, United States

A comparison of typical undergraduate chemistry curricula followed in India and USA shows difference in requirements and perspectives. Four-year liberal arts concept is followed in USA with about 60% course load in chemistry in a typical BS professional degree track. In India, the BS chemistry program is for three years and students study mainly chemistry with two physics and three mathematics courses. There are no general chemistry requirements. The general methodology for lecture courses is similar. But the lab courses are more rigorous in India with 4-5 hours lab all five days in a week throughout the whole academic year. The focus is problem solving, skill development and quantification. In USA, undergraduate research is an important part, while this is almost missing in a BS chemistry program in India. Undergraduate education is offered in colleges affiliated to a university, with curriculum and exams being controlled by the affiliating university.

CHED 225

Research and teaching abroad: Contrasting chemical education in Brazil and the United States

Brian G McBurnett, of Chemistry, University of the Incarnate Word, San Antonio, Texas 78209, United States

This presentation involves observations and experience gained from a semester of teaching and research in Brazil. As a Fulbright Scholar, the presenter taught an undergraduate inorganic class and participated in research at a private university in Rio de Janeiro. Challenges of teaching and living abroad will be discussed. This presentation will focus on a comparison of the pedagogical and cultural differences between institutions in the United States and Brazil with the objective of facilitating future collaborations.

CHED 226

Molecules of life: Introducing chemistry into the culture of elementary school education by way of experiential learning using experiments and art projects

William D. Lubell,épartement de chimie, Université de Montréal, Montréal, Québec H3C 3J7, Canada

Recognizing that chemistry has been traditionally poorly represented in the culture of elementary school education, Molecules of Life (MoL: was launched in Canada to expose elementary school students to chemistry by way of experiential learning using experiments and art projects. Currently in its sixth year, MoL recruits university art and science student volunteers, who have teamed up to produce and deliver presentations in English and French at elementary schools in Halifax and Montreal. Over 40 different projects featuring molecules of life have been created and taught by MoL volunteers employing discussion, experiments and art to captivate the interest of the elementary school students. Moreover, to enhance impact, MoL has recently begun to produce educational videos with the debut of "How to teach 3rd graders about chlorophyll". In this entertaining and informative video, two volunteer actors, students from the arts and sciences, Ms. Molecule and Ms. Life discuss and demonstrate the elements necessary for the set-up, performance and interpretation of a MoL class on the green pigment from plants responsible for photosynthesis. Describing how to extract the pigment from spinach and showing how to use the pigment for painting, they cover a variety of subjects from scientific, historical and artistic perspectives. Our presentation will highlight MoL efforts and issues in bringing chemistry into the culture of the elementary school classroom by way of experiential learning.

CHED 227

Integration of faith and chemistry: Mission field “solutions”

Christopher T Jones, of Arts and Sciences, Brewton-Parker College, Mount Vernon, Georgia 30445, United States

A model for presenting the traditional concepts of solution chemistry to undergraduates in the context of water quality on the Christian mission field will be examined. This model can be used to cover the required information in the same amount of class time while making the topic relevant to students at a faith-based institution of higher education. This model can be used to bridge the gap between the academic discipline of chemistry and an institution's mission statement that encourages the integration of faith and learning.

CHED 228

Pharmacy technician curriculum within a high school health science academy: Where's the chemistry?

Sean P. Madden, Technician Program, Greeley District 6 Health Science Academy, Greeley, CO 80631, United States

The ACS Guidelines and Recommendations for the Teaching of High School Chemistry, (2012) acknowledges that high school students of diverse backgrounds may be exposed to the "big ideas" of chemistry in a variety of contexts. This presentation serves as a case study for how such learning takes place within the Greeley District 6 Pharmacy Technician Class, which is one component of the Greeley Central High School Health Science Academy; sponsored by Banner Health Systems and North Colorado Medical Center.

CHED 229

What are POGIL labs and how are they different?

Frank J. Creegan, of Chemistry, Washington College, Chestertown, Maryland 21620, United States

What distinguishes a POGIL laboratory from a traditional laboratory? What is unique about the POGIL laboratory text material? How does POGIL lab work relate to lecture content? How does student laboratory work in a POGIL setting differ from that in conventional approaches? What role does the instructor play in the POGIL laboratory experience? What are the criteria for POGIL lab experiments? Specific POGIL experiments and experiment outcomes will be used to answer these and other questions about using Process-Oriented Guided Inquiry Learning in the chemistry laboratory.

CHED 230

Development and implementation of guided inquiry experiments for physical chemistry

Alexander Grushow1,, Sally Hunnicutt2, Robert Whitnell3.  (1) Department of Chemistry, Biochemistry & Physics, Rider University, Lawrenceville, NJ 08648, United States  (2) Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23238, United States  (3) Department of Chemistry, Guilford College, Greensboro, NC 27410, United States

The NSF-funded POGIL-PCL project implements the principles of Process Oriented Guided Inquiry Learning (POGIL) in order to improve student learning in the physical chemistry laboratory (PCL) course. POGIL principles are being used to develop inquiry-based physical chemistry experiments that emphasize macroscopic and molecular models of chemical phenomena. We will briefly describe physical chemistry experiments that are under development in areas such as chemical kinetics, solvent effects on chemical equilibria, phase transition behavior, thermodynamics, spectroscopy, and computational chemistry. We will also describe the community of instructors who are collaborating on generating and using POGIL-PCL experiments. This presentation will discuss the general structure of a POGIL physical chemistry experiment with specific examples that are currently being tested with students and give an overview of future workshops in which interested physical chemistry laboratory instructors can become involved in the POGIL-PCL project.

CHED 231

Enriching infrared spectroscopy learning through inquiry-based activities

Sarah A Winget,, Ruth E Riter, of Chemistry, Agnes Scott College, Decatur, GA 30030, United States

Problem-based (PB) laboratory experiments linked to process-oriented guided-inquiry learning (POGIL) activities for student learning of Fourier-transform infrared (FTIR) spectroscopy in analytical and physical chemistry are being developed, implemented and evaluated in a project funded by an NSF TUES Type I grant (#1140391). The POGIL activities will focus on student understanding of key IR spectroscopic concepts. The PB laboratory experiments will provide students with hands-on opportunities to explore fundamental techniques and measurements, including attenuated total reflectance (ATR) spectroscopy, as well as investigate advanced topics such as the characterization of surfaces. All activities and laboratory experiments will be peer reviewed and classroom tested through The POGIL Project. These novel resources will be designed as self-contained modules that may be used in any upper-level undergraduate course by any practitioner wishing to use active learning methods to study FTIR spectroscopy and/or fundamental principles illustrated by FTIR spectroscopy.

CHED 232

Making the Science Writing Heuristic work

Dawn Del Carlo, of Chemistry and Biochemistry, University of Northern Iowa, Cedar Falls, IA 50614, United States

Educators often try to implement new methods and approaches into their teaching but, when faced with inevitable challenges, tend to either abandon the new approach or “tweak” it to something more comfortable, but also, not much different from what they were doing before. This presentation will discuss the basic tenets of the Science Writing Heuristic (SWH) that make it what it is (and consequently, should not be “tweaked”), what elements afford a bit more flexibility, and how they fit together. Specific strategies for modifying existing lab experiments, report format, and student tasks while in laboratory will be presented.

CHED 233

POGIL-Science Writing Heuristic (SWH) hybrid experiments for teaching concepts in introductory organic laboratory

R Daniel Libby,, Moravian College, Bethlehem, PA 18018, United States

For the last four years, I have been using hybrid POGIL/SWH experiments in my introductory organic laboratory. My approach helps students learn fundamental concepts, data processing skills and scientific writing skills while they are acquiring laboratory techniques. Each experiment starts with a question and requires students to propose types of laboratory data to answer it; students also submit an electronic pre-lab assignment to assess their understanding of concepts relevant to the question. In a pre-laboratory discussion students develop a general experimental plan. They then receive a workable procedure for collecting the required data. In the laboratory each student individually collects part of the data. Class data are pooled electronically and a post lab discussion helps the students explore various ways to organize and interpret the total data set in preparation for writing a detailed report. The presentation includes my two-semester lab syllabus and a detailed discussion of one specific experiment.

CHED 234

Implementing student roles in the general chemistry laboratory: Student-led instructor-facilitated guided-inquiry based laboratory (SLIFGIL)

Tanya Gupta1,, Thomas J. Greenbowe2, Kathy A. Burke2.  (1) Department of Chemistry, Grand Valley State University, Allendale, MI 49401, United States  (2) Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States

Previous researchers have demonstrated that students who experienced the Science Writing Heuristic (SWH) approach (a type of guided-inquiry based laboratory instruction) performed academically better than students receiving non-SWH or more traditional laboratory instruction. In the present study implementation of the SWH approach is extended further, with students leading the laboratory session, facilitated as needed by their laboratory instructor. Students are assigned various roles as “experts” that are consistent with components of the SWH approach. Roles include beginning questions expert, safety expert, data table expert, claims expert and evidence and analysis expert. Implementation of student roles in accordance with the SWH approach necessitates a learner-centered classroom environment and accountability on the part of the students. This study was based on a mixed-methods research design. Results of the study indicate that students who were involved in group roles consistent with the SLIFGIL teaching approach performed statistically significantly better on hour exams and laboratory practical exams as compared to students in SWH format laboratories that were facilitated solely by an instructor. Among students in the SLIFGIL group approach there was an increased amount of student-student interaction, a higher level of student preparedness, a superior understanding of the SWH format, and an improved general overall understanding of the concept of the laboratory activity. Further, students produced higher quality writing as a result of undertaking student roles.

CHED 235

Use of an SWH experiment as the model for a POGIL classroom activity

Brandon M Fetterly1,, Kathy A Burke2, Thomas J Greenbowe2.  (1) Chemistry, University of Wisconsin-Richland, Richland Center, WI 53581, United States  (2) Chemistry, Iowa State University, Ames, Iowa 50011, United States

The use of models to build student understanding distinguishes a classroom utilizing POGIL from traditional classrooms. In current published activities, models are presented to students through written material or printed figures. In order to better link lab and lecture content, the observations gained in an exploratory laboratory experiment utilizing the Science Writing Heuristic are used to build the model for a POGIL classroom activity in the following session. This methodology will be shown using observations from a qualitative analysis experiment to build a model for an activity on double replacement reactions.

CHED 236

Using the science writing heuristic in an upper-level laboratory

Caryl Fish,, Steven Gravelle.Department of Chemistry, Saint Vincent College, Latrobe, PA 15650, United States

In an upper-level chemistry laboratory that includes project-based laboratories from both instrumental analysis and physical chemistry, we have used the science writing heuristic (SWH) as the guiding principle for both project design and student written reports. Students turn in proposals for each project that address their beginning questions and develop a method to answer those questions. In their reports students must address the beginning questions, make a claim that answers their question, provide evidence from their data that supports the claim, and then interpret their results based on some outside reading. Student learning was evaluated using primary trait analysis, and coding the reading and reflection section of the lab reports for process skills like information processing and critical thinking.

CHED 237

Incorporating the Science Writing Heuristic across the chemistry curriculum

Steven J Gravelle,, Matthew A Fisher.Department of Chemistry, Saint Vincent College, Latrobe, PA 15650, United States

The Science Writing Heuristic (SWH) has been used in many of the chemistry major laboratory courses at Saint Vincent College since 2005. These courses range from freshman-level General Chemistry to our junior-level Advanced Physical Methods. We have incorporated it across a broad range of courses because (1) it is a “writing to learn” strategy that helps our students to focus on the science underlying the laboratories, (2) it provides a more inquiry-based structure in our laboratories and (3) it helps the students develop the habits of mind necessary for developing a successful senior research project. We will provide examples of ways that we emphasize different components of the SWH in the various laboratory courses to help the students evolve in their approach to scientific thinking and problem solving. We will also briefly describe how the use of the SWH has impacted our senior research program.

CHED 238

Arrowpushing in inorganic chemistry: Charting the limits of the approach

Steffen Berg,, Abhik Ghosh, of Chemistry, University of Tromsø, Tromsø, Norway

While a mechanistic approach ("arrowpushing") is universally adopted in introductory organic chemistry, a similar approach is not used for introductory inorganic chemistry. A perusal of introductory inorganic texts currently available on the market revealed a complete lack of mechanistic rationale, as far as descriptive main-group chemistry is concerned. In a recent article (Berg, S.; Ghosh, A. J. Chem. Educ. 2011 , 88, 1663-1666), we argued that there was little justification for this state of affairs to continue. But just how far can an arrowpushing approach be pushed to teach main-group reaction chemistry? The answer, we believe, is 'very far indeed'. We will illustrate our approach by discussing some of the more stoichiometrically complex reactions that one encounters in standard undergraduate inorganic texts.

CHED 239

Incorporating catalysis in the undergraduate inorganic chemistry lecture and laboratory

Bradley M Wile, of Chemistry and Biochemistry, Ohio Northern University, Ada, OH 45810, United States

This talk will describe efforts to incorporate catalytic cycles into the first undergraduate inorganic chemistry course at Ohio Northern University. Activities in the lecture and laboratory portions of this course are integrated, and students are encouraged to explore implications of catalysis in small groups. At the conclusion of each activity, each group communicates their findings, and some generalizations are made as a whole.

CHED 240

Utilizing metallacrowns for a multi-week upper-division inorganic laboratory

Curtis M. Zaleski, of Chemistry, Shippensburg University, Shippensburg, PA 17257, United States

Students engage in a multi-week, upper-division inorganic laboratory that explores four different metallacrown compounds. This report provides experimental details regarding the syntheses and characterization techniques, including cyclic voltammetry, solid state magnetic susceptibility, FT-IR, UV-Vis, and paramagnetically shifted 1H-NMR. In addition, data sets and spectra are provided for the characterization methods. A general course outline is also provided for the different laboratory sessions. The premise of the project is to mimic a research laboratory atmosphere in a controlled teaching environment. The students are expected to explore the primary literature and to develop characterization conditions for their particular metallacrown. The metallacrown laboratory also serves as a capstone to the inorganic course as multiple lecture topics and laboratory techniques are combined in the last weeks of the semester. Furthermore, the topic of metallacrowns allows the instructor to combine a variety of principles from other chemistry disciplines such as organic and analytical chemistry.

CHED 241

Increasing student comprehension in inorganic chemistry through use of online homework

Jason S. Overby, of Chemistry and Biochemistry, College of Charleston, Charleston, SC 29424, United States

While online homework is a well-tested and well-understood technology for prep, intro, general, and organic chemistry courses, its use in upper-level courses like inorganic chemistry is minimal at best. To help with student comprehension and understanding of advanced topics covered in a senior-level inorganic chemistry course, online homework has been employed. An overview of the material and results from its use will be described.

CHED 242

Investigating the effects of online homework on student achievement in chemistry

Diane M Bunce,, Matthew Tomney, Ashlie Wrenne.Chemistry, The Catholic University of America, Washington, DC 20064, United States

Online Homework is used in a variety of chemistry courses. Faculty who have overcome the technological hurdles endorse it because it forces students to keep up with their homework and to receive grades and feedback in a timely manner. Educational theory supports the benefit of immediate feedback in learning. Book publishers have built in the ability to set different parameters to better meet the needs of faculty of both large and small classes. Research reporting on student satisfaction with Online Homework reports student satisfaction with Online Homework, but does Online Homework affect student achievement? This study conducted across three semesters with two different teachers teaching the same course and using Online Homework does not show a definitive advantage for student achievement. What is missing? Is it the experimental design, the specific implementation of the Online Homework or the Online Homework itself? This and other questions will be discussed.

CHED 243

Forays into blended learning with interactive digital content

Bernadette Harkness, of Chemistry, Delta College, University Center, MI 48640, United States

Among the many innovations in teaching chemistry in recent years, technology has played a huge role as many educators embrace the use of tools such as clickers, online homework, animations and videos to name a few, to increase student engagement and to offer diverse learning modes. Some of these tools can be used in both traditional on-campus classes as well as for distance learning classes. This use of technology also extends to online content delivery and is being used more frequently to blend online and on-campus learning experiences. This blended learning approach can offer opportunities for increasing classroom time for more active learning exercises or for decreasing classroom time to shift to a more distance learning format. This discussion will focus on the use of webpage authoring tools that can deliver online content with engaging and interactive experiences for the student to learn and master basic chemistry fundamentals. Student feedback and assessment data of their learning experiences will also be reported to show the effects of online content delivery in both traditional on-campus and hybrid (lecture online/ lab on-campus) introductory chemistry classes.

CHED 244

Targeting higher levels of learning in the general chemistry series by using Marzano's Taxonomy

Santiago A. Toledo1,, Justin M Dubas2.  (1) Department of Chemistry, Texas Lutheran University, Seguin, TX 78155, United States  (2) Department of Economics, Texas Lutheran University, Seguin, TX 78155, United States

This presentation provides a framework to help chemistry students develop higher order thinking skills. Marzano's Taxonomy gives a theoretical framework for learning that can be adapted as a useful model in the chemistry classroom. This adaptation is used to develop student learning outcomes for courses in the general chemistry series with the goal of intentionally targeting higher levels of learning. The taxonomy based learning outcomes are used to design classroom activities as well as formative and summative assessments mapped to specific levels of the cognitive process. With an explicit focus on higher-levels of learning, students are able to ascertain specific strengths and weaknesses they have within a learning outcome in relation to the levels of the cognitive process. Faculty can use the results of these assessments to easily identify problem areas in terms of learning outcomes and progress in a student's cognitive development, allowing a differentiated approach to student learning.

CHED 245

Factors to identity that enhance student learning, success, and retention in general chemistry in an inner city university

Michael J Castaldi1,, Hamid Yazdekhasti1, Christopher Edmin2, Felicia Mensah2, Catalina Adorno1.  (1) Department of Chemistry, St. Peters University, Jersey City, New Jersey 07306, United States  (2) Science Education, Teachers College, New York, New York, United States

The problem of retention and success for introductory physical science courses has been a continued problem for undergraduate science departments. Nowhere has the problem been more an issue than in General Chemistry. As this is often the "gatekeeper" for many of the sciences it is often the make or break for someone choosing to major or to have a career in a science. Over the years there have been many attempts to break this cycle but with very limited success. The literature is full of studies but, the high drop rate after the first and second semesters of general chemistry still continues. With the need to attract and keep science and engineering students we have attempted to track our incoming general chemistry students and try to identify factors that might be relevant to undergraduate success in the physical sciences. We have initiated some new and creative ways which included interviews, student focus groups, attitude surveys, online homework as well as diagnostic pre and post tests. We will present some of our preliminary findings and results.

CHED 246

Creating connections: Introducing scientific literature research in the undergraduate general chemistry laboratory

Margaret Bruehl1,, Denise Pan2, Ignacio Ferrer-Vinent2.  (1) Department of Chemistry, University of Colorado Denver, Denver, CO 80217-3364, United States  (2) Auraria Library, University of Colorado Denver, Denver, CO 80217, United States

The University of Colorado Denver (UCD) Chemistry Department is collaborating with the Auraria Library on a case study to quantify the benefits students receive in their education by using library collections. Over the last three academic years, students enrolled in Honors General Chemistry I and II Laboratory courses have completed units focused on scientific literature. The goal is to introduce students to the rich resource of scientific literature early in their undergraduate studies. A science librarian presents library instruction targeted at topics the students have encountered in previous lab work and lecture material. Then, the post-lab assignment challenges students' comprehension and creativity to use library and non-library resources to explore appropriate topics in the scientific literature, with the ultimate goal of identifying ideas for new general chemistry laboratory experiments. While searching the literature, students record their research process by capturing information on the scientific databases accessed as well as search terms and refinements used, and documenting chosen citations in ACS format. At the end of each semester, this information is gathered, along with assignment and course grade data from each participating student, and is analyzed by the authors of this paper in order to identify misconceptions in student learning, evaluate the effectiveness of library instruction, find insights into teaching information literacy, and estimate the return-on-investment (ROI) of library materials. The results of this case study can shed light on the role of library instruction and teaching information literacy to students early on in their undergraduate science education. Long term, this case study can assist libraries in making informed decisions on where to invest their resource dollars and the effective integration of library and freely available resources.

CHED 247

Infrastructure requirements of the ACS Guidelines

Laura Kosbar1,, Cynthia K. Larive2,  (1) IBM T.J. Watson Research Center, Yorktown Heights, NY 10547, United States  (2) Department of Chemistry, University of California - Riverside, Riverside, CA 92521, United States

The infrastructure requirements of the 2008 Guidelines provide a foundation for program excellence. Faculty and instructional staff are the main drivers of undergraduate programs therefore contact hours are limited to 15 hrs per week, with some flexibility for averaging. A minimum of 4 faculty members are required with at least 3/4ths PhDs. The 2008 Guidelines require that programs maintain a suite of modern instruments (including a functioning NMR) and specialized laboratory apparatus for student use, as well as providing students and faculty access to Chemical Abstracts and at least 14 current journals.

The past five years have witnessed rapid changes in the staffing of many chemistry programs, with increases in the numbers of temporary and non-tenure track instructors. Electronic access to chemical information is changing rapidly and modes of interaction with instrumentation, including remote access, could allow other paradigms for chemistry instruction. Updated guidelines may need to address these changes.

CHED 248

Discussion of infrastructure needed for an approved program

Laura L. Kosbar1, Cynthia K. Larive2,  (1) IBM T. J. Watson Research Center, Yorktown Heights, NY 10547, United States  (2) Department of Chemistry, University of California, Riverside, Riverside, CA 92512, United States

This session will provide an opportunity for the attendees at this symposium to engage in a conversation about infrastructure requirements for approved programs. The discussion will focus on faculty and technology. Topics of the discussion will include appropriate maxima for teaching loads for both tenure-track faculty and other individuals who are involved in course delivery. We are also interested in the balance between faculty and instructional staff in course delivery. We will explore how the revisions to the Guidelines should reflect changes in information resources and their modes of delivery as well as how changes in technology affect the ways in which students work with instrumentation.

CHED 249

Development of student skills and the role of research in the undergraduate curriculum: Implications for the ACS guidelines

Joel I. Shulman1,, Edgar A. Arriaga2,  (1) Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States  (2) Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States

While formal coursework provides students with education in chemical concepts and training in laboratory practices, students need to learn more than course content alone to be effective and productive scientists. They need to master a variety of skills that will allow them to become successful professionals, including problem solving, laboratory safety, use of the chemical literature, oral and written communication, team building, and ethical behavior. These skills can be imparted and assessed throughout the chemistry curriculum. Undergraduate research is an important experience that reinforces development of these skills while at the same time providing students the opportunity to integrate concepts learned in class into the broader context of a research question. The treatment of student-skill development and undergraduate research in the revised ACS Guidelines will be discussed.

CHED 250

Discussion of skills required for a certified major

Edgar A. Arriaga1,, Joel I. Shulman2,  (1) Department of Chemistry, University of Minnesota - Twin Cities, Minneapolis, MN 55455, United States  (2) Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221, United States

The importance of skill development in undergraduate programs is becoming increasingly evident. During this session we will focus on the range of skills certified majors should gain by the time they graduate, how students can obtain these skills, and how the Committee on Professional Training can assess the effectiveness of programs to develop these skills in their students. We will also consider the role of undergraduate research and how it can be used to help develop student skills. This session will consist of both small group discussions as well as discussion in the larger group.

CHED 251

Undergraduate curriculum and the ACS Guidelines

Clark R. Landis1,, Anne B. McCoy2,  (1) Department of Chemistry, University of Wisconsin - Madison, Madison, WI 53706, United States  (2) Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, United States

A central feature of the undergraduate experience is the courses that students are required to take. With the 2008 Guidelines, the course requirements for certified majors were made more flexible. Specifically, students have foundation level experiences in each of the five sub-disciplines of chemistry (analytical, biochemistry, inorganic, organic and physical) as well as four in-depth courses. In addition to the lecture courses, students should have at least 400 hours of laboratory, which covers at least four of the five sub-disciplines of chemistry. Further, approved programs need to teach the foundation courses in the five sub-disciplines, and offer four in-depth courses annually. In this talk, we will review the current requirements, as well as discuss areas where changes may be introduced during the revision of the guidelines that is presently underway. We will also describe various approaches for introducing areas of chemistry that span multiple sub-disciplines or which represent evolving areas in chemistry.

CHED 252

Discussion of the curriculum for the certified major

Clark R. Landis1,, Anne B. McCoy2,  (1) Department of Chemistry, University of Wisconsin - Madison, Madison, WI 53706, United States  (2) Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, United States

During this session we will conduct a discussion of topics related to the curriculum a certified major must complete. In the 2008 Guidelines, considerable flexibility was introduced into the curriculum. Part of the motivation for the flexibility is to allow programs to include subjects that are appropriate for the students they are teaching. There must always be a balance between flexibility and ensuring students have an appropriate exposure to a broad range of topics that don't naturally fall into the five sub-disciplines of analytical, biochemistry, inorganic, organic, and physical chemistry. Such topics include, but are not limited to, green chemistry, polymer chemistry or material science. Much of the discussion will focus on these issues. In addition, the Guidelines currently stipulate that programs must teach foundation courses annually and must teach a minimum number of in-depth courses each year. We will discuss how this requirement affects programs, particularly when small-enrollment courses are involved.

CHED 253

Effect of phytohormones in nutrient uptake by coriander plants in soil-compost system

Taina Rodríguez-Curet1,, Martha López-Moreno2.  (1) Department of Biology, Chemistry and Environmental Sciences, Inter American University of Puerto Rico - San Germán, San Germán, Puerto Rico  (2) Department of Chemistry, University of Puerto Rico, Mayaguez, Puerto Rico

Food shortage is a worldwide problem; to produce foods containing greater amount of nutrients may be a solution. Different soils contain diverse nutrient content. Compost in soil behaves as fertilizer, provides micro and macro-nutrients and increases its retention. Also, it has other properties that contribute significantly to the growth of plants. Phytohormones are chemical substances occurring naturally in plants; they are responsible for regulating the physiological processes of plants. The aim of this research was to enhance the nutrient uptake of Coriandrum sativum (Coriander) in soil-compost systems using phytohormones. Leaves and stems of coriander were analyzed for micro and macro nutrient uptake by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). Results showed that coriander plants grown in soil or soil- compost system treated with phytohormones contained higher amount of nutrients. These results may suggest that phytohormones can increase the nutrient uptake by coriander plants, but additional studies are needed.

CHED 254

Characterization of alternate grains used in the brewing process and analysis of product parameters

Grant D Newton,, Francis M Mann.Department of Chemistry, Winona State University, Winona, Minnesota 55987, United States

In recent months, an interest has arose in the gluten content of beer, both traditional and gluten free. During the first part of my research, a few gluten free beers were tested using an ELIZA (EZ Gluten) test to determine if there was any gluten in the beer. The results showed that the gluten free beers did not contain gluten. Following this analysis, I have analyzed alternate grains, (sorghum, rice, corn, quinoa), as well as barley, to determine if any gluten is extracted during the fermentation process. During the process, standard tests used during the brewing process are used on the alternative grain fermentation to determine if the grains are a plausible alternative to standard grain used. The tests include relative ethanol fermentation, a Brix test to determine sugar content and consumption, and a total protein assay to determine the proteins extracted by the fermentation process.

CHED 255

Determination of metals in pet food

Karolyn Barker,, Donald L Wharry.Department of Chemistry, St. Edwards University, Austin, Texas, United States

A rise in the amount of pet food recalls within the past few years has caused
concern over the health and safety of pets, as well as regulations. Metals that are not listed on labels can have harmful impacts on the animals, especially long-term. Iron, nickel, cadmium, copper, and chromium concentrations were tested through AA spectroscopy. RfD values for humans were used for nickel, cadmium, and chromium because there are not values set for animals. One was over the value for copper of a 33lb dog. Iron averaged 2x too high, nickel averaged about 1x too high, chromium ranged from 2-6x too high, and cadmium averaged about 4x too high. For 9lb cats, copper was about 2x higher than the RfD, 1.5x too high for Iron, 3x for nickel, 3-20x too high for chromium, and 5-8x too high for cadmium. Further research will aim to evaluate more samples and metals.

CHED 256

Correlation of logD(Oct) and chromatographic logk' values for the catechol flavones

Josh D. Hernandez,, Chin Yeow, Katie Loving, Hannah Sigal, Margaret J. Risher, William L. Whaley.Chemistry, Geosciences and Environmental Science, Tarleton State University, Stephenville, Texas 76402, United States

The flavones represent a class of natural products that are contained in fruits and vegetables. These compounds function as anti-oxidants to protect cells from reactive oxygen species (ROS). The ortho-dihydroxy group, also called a catechol group, is one of the structural features of flavones that confer high radical scavenging activity. The presence of a catechol group increases the polarity of flavones and this may affect membrane permeability. The logarithm of the octanol/water partition coefficient, or logP(Oct), is a descriptor that is an index of the hydrophobicity of a molecule. For flavones, it is more appropriate to measure distribution coefficients, or logD(Oct) values, because the hydroxyl groups of several catechol flavones have pKa values less than 9.0. The distribution coefficient was determined using 1-octanol equilibrated with MOPS buffer (pH=7.4) in the aqueous phase. For a group of related compounds, the values of logD(Oct) have often been correlated to the logarithm of the chromatographic retention factors (logk' values) to verify their accuracy. Each catechol flavone including 7,8-dihydroxyflavone (7,8DHF), 6,7-dihydroxyflavone (6,7 DHF), 5,6-dihydroxyflavone (5,6DHF), 2',3'-dihydroxyflavone (2',3'DHF) and 3',4'-dihydroxyflavone (3',4'DHF) were assayed by the “shake-flask” method to determine the value of logD(Oct). The values of LogD(Oct) were correlated with values of Logk' that were determined using an octadecylsilane (C-18) stationary phase and a polar mobile phase. A good correlation with an R2 value of 0.93 was observed. The compound 3,2'-dihydroxyflavone (3,2'DHF) was also included in the study because it has exhibited some of the physical and chemical properties that are typical of true catechol-flavones. Nuclear magnetic resonance spectroscopy was used to demonstrate that this compound can exist in two different conformations that allow it interact with either polar or non-polar solvent molecules. (This research was supported financially by the Welch Foundation Departmental Research Grant Program, the Tarleton Organized Research Program, and the Tarleton REAL Program.)

CHED 257

Quantification of urea in a controlled-release fertilizer

Joshua L Neeper,, Ron E Hemingway, Frederick F Shriner, IV, Blakely M Adair.Department of Chemistry, The Citadel, Charleston, South Carolia 29409, United States

Nitrogen is one of three macronutrients commonly used in plant fertilizer; the other two being phosphorous and potassium. The focus of this experiment was to determine the rate of release of a newly formulated controlled-release solid formulation of nitrogen containing urea fertilizer, after having been exposed to soil over a specified period of time. The fertilizer pellets varied in size and urea content. The desired outcome was a slow and uniform reduction of urea in the fertilizer pellets over time. Multiple concentrations and sizes of fertilizer pellets were analyzed. UV-visible spectrometry was employed to determine the concentrations of nitrogen from urea by comparing its absorbance at 470nm against a set of urea nitrogen standards. The results show that the expected concentrations before the fertilizer was applied to the soil are accurate. The nitrogen concentrations in some post application samples are inconsistent with the preliminary mass difference data.

CHED 258

Antioxidants and polyphenol activity: It's getting hot

Kimberlee Daus, Dviti P Mody, of Chemistry, Belmont University, Nashville, Tennessee 37212, United States

In the past three decades research regarding antioxidant activity has gained attention. Antioxidant, found abundantly in fruits, can reduce oxidative damage that is caused by free radicals. Antioxidants safely interact with free radicals to terminate the chain reaction before vital molecules like DNA are damaged. Polyphenols are a type of antioxidant that have great abundance in our diet and help with prevention of cancer and cardiovascular diseases. The aim of this research is to investigate the effect of heat on the activity of polyphenols in fruits such as blueberries, apples and grapes. The polyphenolic activity of the fruits was tested using the TEAC test and DPPH assay. The anticipated results should indicate an increase in polyphenolic activity of these fruits, and thus, an increase in nutritional value.

CHED 259

Dissolution of cellulose with Fe-containing magnetic ionic liquids

Stephanie A Hall,, Clint W Williford.Department of Chemical Engineering, University of Mississippi, Oxford, Mississippi 38655, United States

The focus of this project is to determine the effectiveness, in the preprocessing of biomass, of a magnetic ionic liquid 1-butyronitrile-3-methylimidazolium tetrachloroferrate (nbmim[FeCl4]) as a catalyst. Lignocellulose is a promising starting material for bioproducts, ranging from biofuels to specialty chemicals; however, lignocellulose is resistant to enzymatic degradation. Various biomass-preprocessing techniques such as mechanical, microbial, and chemical pretreatment are used for increasing the digestibility of biomass to sugars for ethanol production. A variety of ionic liquids have demonstrated the capability to degrade lignocellulose. However, after degradation separation of biomass and ionic liquids has proven to reduce the economic potential of this pretreatment process. The addition of magnetic properties to the ionic liquid can be used to stabilize the ionic liquids and prevent its loss or other unfavorable fluid/fluid interactions in the bioreactor. Therefore, overcoming separation is an important priority for the progress of the lignocellulosic biorefinery concept.

CHED 260


CHED 261

Expressed sequence tag for DNA polymerase alpha

Rebecca Krewer,, Ira Simet.Department of Chemistry and Biochemistry, University of Northern Iowa, Cedar Falls, Iowa 50613, United States

Replicative DNA polymerases have a role in the control of DNA synthesis and are potential targets for stopping unregulated cell growth, such as cancer. DNA polymerase alpha, which assembles RNA primers and initiates replicative synthesis, represents a model enzyme in the study of this control. This enzyme is composed of a priming subunit, a catalytic subunit, and two structural subunits. Several primers developed from known enzyme gene sequences have been used to identify an expressed sequence tag (EST) in the catalytic subunit of the enzyme in embryonic chicken brain. The sequence of the EST matches a published chicken genomic DNA sequence. This EST will be used in real time PCR to help quantitate DNA polymerase alpha catalytic subunit mRNA under various growth conditions.

CHED 262

2-Octadecynoic acid displays antineoplastic activity against neuroblastoma via lactate dehydrogenase release

Gabriel A Cintrón,, Elsie A Orellano, Néstor M Carballeira.Department of Chemistry, University of Puerto Rico Río Piedras Campus, San Juan, Puerto Rico 00931-3346, Puerto Rico

Recently, our research work demonstrated that the 2-octadecynoic acid (2-ODA) displays antineoplastic activity, against the neuroblastoma SH-SY5Y cell line (EC 50 = 26.0 ± 2.0). Moreover, we found that the 2-ODA is an inhibitor of the human topoisomerase IB enzyme, a possible intracellular target for this fatty acid. To further characterize the cell death response by 2-ODA we assessed caspase-3 activation and lactate dehydrogenase (LDH) release. We found that 2-ODA promoted LDH release, which is a cell death mechanism principally associated to necrosis. Thus, 2-ODA promotes cancerous cell death by a death mechanism independent of caspase-3 activation, but dependent of LDH release. For this reason, our results suggest a specific mechanism of action for 2-ODA through cell membrane breakdown. 2-ODA could be the first of many such class of novel acetylenic fatty acids with antineoplastic activity. Our research work highlights a fundamental step forward towards the eradication of cancer.

CHED 263

Comparison of insulin and insulin-like receptors from bean beetles and mammals

Shawn Mercer,, Richard Singiser.Department of Natural Sciences, Clayton State University, Morrow, GA 30260, United States

Previous studies have been completed on bean beetles and morphological changes. These studies identified changes in morphology related to growth on different mediums. Current work is aimed at determining the biochemical effects the insulin-like receptors may cause, leading to morphological changes. Using this knowledge, experiments to isolate the bean beetle insulin-like receptor will be completed. After isolation, comparisons between the insulin-like receptor of bean beetles and the mammalian insulin receptor can be made using ligands specific to both the mammalian insulin receptor and bean beetle insulin-like receptor. Both conserved and divergent residues will be identified in this comparison leading to focal points for further studies. These conservative and divergent areas should help identify regions related to control of the morphological changes observed in bean beetles. In addition, study of these areas in the insulin-like receptor could present knew knowledge about the workings of the mammalian insulin receptor.

CHED 264

Study of secondary structure of cpTat system component, Tha4, by EPR spectroscopy

Karolin Emia Ginting1,, Amanda Storm1, Carole Dabney-Smith1,2.  (1) Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States  (2) Cell, Molecular and Structural Biology Program, Miami University, Oxford, Ohio 45056, United States

Chloroplast Tat (twin arginine translocation) pathway is responsible for transporting fully folded precursor proteins into the thylakoid lumen using only the proton motive force for energy via the assembly and activity of three membrane-bound components: Tha4, Hcf106, and cpTatC. The arrangement of Tha4 in the membrane has significant implications on how it could function during translocation, yet little is still known about its oligomer organization. As a prelude to structural studies of the Tha4 oligomer, we present the secondary structure of Tha4 in the membrane as determined using site-directed spin labeling electron paramagnetic resonance (SDSL EPR) spectroscopy. Single cysteine substitution is introduced in various positions of Tha4 through primer-based mutagenesis and subsequently labeled with a nitroxide spin label. Integration of this protein to synthetic lipid membranes was subjected to power saturation and continuous wave EPR (CW-EPR) experiments. These methods allows us to more accurately map the transmembrane domain of Tha4.

CHED 265

Single base changes in DNA discriminator show large effects on transcription initiation thermodynamics

Stephanie Chong-Macias1,, Emily Ruff2, Noah Bown2, Tom Record2.  (1) Department of Chemistry, University of the Incarnate Word, San Antonio, TX 78209, United States  (2) Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States

Transcription initiation occurs in a several-step mechanism, whereby RNA polymerase (RNAP) recognizes and binds to DNA and forms an opened RNAP-promoter complex (RPo). We aimed at determining which of the interactions occurring between RNAP and DNA promoter affected RPo complex formation the most. DS4 and DS5 variants were studied. They differed in length by two base pairs of a phage promoter λPR (DS4 and DS5: 8 base pairs; λPR: 6 base pairs), and varied in sequence from each other at one base pair position. To determine if such discriminator variations cause any effect on RPo stability, various filter binding dissociations were performed at different temperatures and a permanganate footprinting reaction was performed for both variants. Through these experiments it was seen that the change between λPR and DS4 only affected the lifetime of open complex, while the variations in DS5 also caused large and surprising effect on the system's thermodynamics.

CHED 266

Identification of proteins that interact with the arabidopsis SYN3 cohesin protein

Dirk Auman,, Yuan Li, Kayla Zehr, Christopher Makaroff.Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States

The cohesin protein complex is vital for holding sister chromatids together during cell division. In Arabidopsis thaliana, α-kleisin proteins are the connectors of two structural maintenance proteins in the cohesin complex. The four α-kleisin proteins found to be vital to sister chromatid cohesion in Arabidopsis thaliana are SYN1, SYN2, SYN3, and SYN4. The behavior of SYN3 was examined in previous research, and it was found not to aggregate around chromosomes in the way SYN1, SYN2, and SYN4 do; instead, its predominant localization in the nucleolus lead to the hypothesis that SYN3 is involved in transcriptional regulation. By employing a yeast two-hybrid assay to screen for SYN3-interacting proteins and using subsequent co-immunoprecipitation and western blotting to confirm the potential interactions, SYN3's putative role in transcriptional regulation was investigated. SYN3 was ultimately shown to interact with a number of known transcription factors, suggesting a regulatory function in gene expression for the protein.

CHED 267

Studies towards the development of a colorimetric method for determination of bacterial concentration

Alaina N. Nunn,, Stephanie A Brouet, Tami L. Sivy.Department of Chemistry, Saginaw Valley State University, University Center, MI 48710, United States

The synthesis of a cephalosporin that could lead to the development of a new colorimetric test for bacterial concentration is described. This highly conjugated compound contains a strained four-membered ring, which is readily opened upon attack of β-lactamase, causing the release of the compound's 3-substituent (2-mercaptopyridine-N-oxide). The release of the 3-substituent is important because it forms a violet-colored complex with Fe, allowing for a colorimetric method for determining bacteria concentrations to be developed. Without the β-lactamase produced by bacteria there would be no release of the 3-substituent, and hence, no color change. Therefore, a correlation may be made between the intensity of the violet color and the concentration of bacteria present. The color changes will be followed quantitatively by measuring changes in absorption using UV-VIS, and this data will then be used to form a calibration curve which will show the relationship between bacteria concentration and the color change's absorptions.

CHED 268

Structural studies of CTCF

Lyanne M Gomez-Rodriguez1,, Ronen Marmorstein2, Jasna Maksimoska2.  (1) Department of Chemistry, University of Puerto Rico, San Juan, Puerto Rico 00931, Puerto Rico  (2) Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6059, United States

CCCTC-binding factor (CTCF) is an ubiquitous, 11 zinc finger (ZF) protein that binds to many sites in the genome and is an important regulator of different cellular processes essential for normal cellular development. It is known that CTCF binds to DNA through its 11 ZF binding region, however molecular details and role of individual fingers in that interaction are not known. To reveal the mechanism for DNA binding specificity by CTCF, we aim to determine the crystal structure of relevant CTCF - ZF domain in complex with target DNA sequence. For this, the protein will be expressed in bacterial cells and purified to homogeneity. Purified protein alone and in complex with DNA will be exposed to various crystal screening conditions to obtain crystals. Once we have crystals, x-ray diffraction data will be collected in order to solve the structure of CTCF and CTCF/DNA complex.

CHED 269

Stability of native state beta2-microglobulin

Laylee E. Ghafar,, Stephanie Gould, John M. Richardson.Department of Chemistry, Austin College, Sherman, TX 75090, United States

Β2-microglobulin (β2m) is a small, 99 residue protein, is a major component of the formation of amyloid fibrils in dialysis-related amyloidosis-a disease associated with renal failure and the deposition of insoluble amyloid fibrils in the musculo-skeletal system. This research is focused to understand the mechanism behind the formation of amyloid fibrils, which includes the analysis of the unfolding transition of β2m. To determine the free energy, ΔG, of the native state, the conformational transition was monitored by the use of a chemical denaturant, guanidinium hydrochloride (Gdm-HCl). Unfolding was followed by fluorescence emission of the amino acid tryptophan. Literature reports differences in ΔG values depending upon identity of chemical denaturant used. Differences in the unfolding in different denaturants may indicate a possible mechanism for the identification of the amyloidgenic species. Our preliminary results showed cooperative unfolding using Gdm-HCl, and gave higher ΔG values then those previously published in literature.

CHED 270

How does rev regulate retroviral integration in HIV

Tam Vo,, Nicholas Fitzkee.Department of Chemistry, Mississippi State University, Starkville, MS 39759, United States

The catalytic core domain (CCD) of HIV-1 Integrase can shuttle cDNA from the virus to the host genome. This interaction is strictly controlled by the HIV Rev protein. Rev is required for successful integration, and the CCD-Rev interaction is a potential target for new AIDS treatments. Structural details of this interaction remain unclear; without it, progress in drug development is limited. Recently, a new method has been developed to make both the Rev protein and the CCD more soluble, facilitating characterization by biomolecular NMR spectroscopy. We present a simple method for the expression and purification of the Rev protein. Rev is fused to a Lipoyl domain during expression. This additional domain resolves the solubility issues that plagued prior work. Rev can then be purified by Ni-affinity column chromatography, ion exchange, and gel filtration and characterized spectroscopically. Characterization of the Rev-CCD interaction via NMR titrations will be also be described.

CHED 271

Synthesis of transition state analogs of the AI-1 synthase RhlI

James Annand,, Scott Ulrich.Department of Chemistry, Ithaca College, Ithaca, NY 14850, United States

Quorum sensing is a bacterial communication system that involves the production and detection of small signaling molecules called autoinducers. Bacteria sense autoinducer concentrations to gauge their cell density, and use this information to initiate cell-density dependent transcriptional changes. The main class of autoinducers are the acyl homoserine lactones or AI-1 molecules. They are made by LuxI family of AI-1 synthases and detected by the LuxR family of AI-1 receptors. We aim to design and chemically synthesize transition state analogs of the P. aeruginosa AI-1 synthase, RhlI. These molecules will be useful both as potential inhibitors of RhlI as well as ligand for X-ray crystallography experiments to elucidate the mechanism of RhlI.

CHED 272

tRNA synthetases show “extreme” features in oral pathogens

Eric Trejo1,, Ashley Van-Orden1, Rachel Yomtob2, Vern Winston2, Caryn Evilia1,2.  (1) Department of Chemistry, Idaho State University, Pocatello, ID 83209, United States  (2) Department of Biological Sciences, Idaho State University, Pocatello, ID 83209, United States

tRNA synthetases are essential enzymes that are required for protein synthesis and evolutionary changes should be evident in their protein sequences.Our lab has found that extremophile organisms, like Halobacterium, have peptide insertions that confer increased stability to the tRNA synthetases under extreme conditions. To see if other potentially “extreme” organisms might have the same features, we used protein alignments and computer modeling to find tRNA synthetases that fit a similar pattern. We found a group of pathogenic organisms (Prevotella intermedia, Fusobacterium necrophorum, and Porphyromonas gingivalis) whose cysteinyl and arginyl-tRNA synthetases had peptide insertions around the active site of the enzymes. This leads us to conclude that peptide insertions may be an adaptation to their “extreme” environment. We are currently characterizing these enzymes in an attempt to discover a novel mechanism of inhibition, which may lead us to a novel therapy for this disease.

CHED 273

Elucidating the enzymatic mechanism of epi-isozizaene synthase

Carina Chittim,, Kevin Litwin,, Scott Ulrich.Department of Chemistry, Ithaca College, Ithaca, NY 14850, United States

Terpene cyclases are enzymes that catalyze the formation of terpene natural products from linear isoprenoid pyrophosphates. The cyclases catalyze carbocation formation of these precursors followed by complex carbocation chemistry to generate the terpene hydrocarbon framework. Epi-isozizane synthase, which generates the terpene epi-isozizaene, has a complex carbocation cascade mechanism and has a known three-dimensional structure by X-ray crystallography. However, how it manages the carbocation chemistry en route to the product remains poorly understood. It is the goal of our lab to address the question of how epi-isozizaene synthase funnels the reaction cascade towards its unique product. We seek to synthesize ammonium and sulfonium analogs of the carbocation intermediates and co-crystallize them with the enzyme. These co-crystal structures will collectively shed light on the enzymatic reaction mechanism.

CHED 274

Molecular and cellular characterization of arabidopsis SCC4

Nicole M Fisher,, Jessie L Ellis,, Eric Wynn, Li Yuan, Christopher Makaroff.Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States

Cohesion complexes hold sister chromatids together during mitosis and meiosis and play a role in DNA repair and transcription. Cohesin binding is dependent upon the SCC2/ SCC4 adherin complex. Previous studies have shown that inactivation of SCC2 or SCC4 in yeast results in lethality. In humans, SCC2/SCC4 mutations that alter the expression and/or activity of the proteins result in complex developmental abnormalities. In this study, the role of SCC4 in the model plant Arabidopsis is being determined. We have shown that inactivation of SCC4 results in embryo lethality. To better understand the role of SCC4, particularly during meiosis and mitosis, transgenic plants in which SCC4 levels are reduced by RNA interference are being generated. Specifically, three lines of plants will express SCC4 RNAi constructs from the constitutive 35S, inducible PX7, and meiosis-specific DMC1 promoters. The effect of SCC4 knockdown on meiosis, mitosis, gamete development, and embryogenesis will be analyzed.

CHED 275

Identifying the interacting partner protiens of cohesin SYN3

Spenser M Pruett,, Kayla R Zehr, Li Yuan, Christopher A Makaroff.Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States

Cohesins are critical for holding a pair of sister chromatids together before segregation during cell division, as well as a variety of other processes. The core cohesin complex consists of 4 proteins: SMC1, SMC3, SCC3, and an ɑ-kleisin. In Arabidopsis thaliana, the 4 ɑ-kleisin proteins are SYN1, SYN2, SYN3, and SYN4. SYN3 was found to be enriched in the nucleolus and is crucial for gametophyte growth. Recent studies have also shown that SYN3 cohesins in animal cells may have regulatory roles in transcription. Utilizing the Matchmaker Gold Yeast Two-Hybrid Assay, SYN3 was tested against a protein library to screen for potential interacting partners. Over 60 proteins were determined to be candidates for SYN3's interactome. Among these partners were a number of chloroplast-localized proteins including FTSZ-1: the Arabidopsis homolog of the bacterial Z-ring protein. These interactions are interesting because SYN3 has never been shown to have a role in the chloroplast.

CHED 276

Structural characterization of antierior gradient 2 protein and its role in pancreatic cancer

Amielia G Adams,, Shuisong Ni, Michael A. Kennedy.Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States

The protein Anterior gradient 2 (Agr2) is highly expressed in pancreatic ductal adenocarcinoma (PDAC), and plays a role in the spread of pancreatic cancer cells. While Agr2's structure and molecular level role in PDAC remains unknown, the structure of its homologue Agr3 was recently deposited into the PDB bank. The primary goal of this study is to better understand the structure of Agr2 through x-ray crystallography and NMR spectroscopy. To prepare the protein for structural studies, Agr2 was cloned without its 20 N-terminal amino acid signal peptide (Agr2 d20) and without an additional N-terminal 30 amino acids because of low sequence complexity and predicted structural disorder (Agr2 d50). Using bioinformatics, site-directed mutagenesis was also performed to reduce predicted surface entropy. Crystal trials and preliminary HSQC 15N labeled NMR spectra of Agr2 d20 were unsuccessful and indicated the protein formed a dimer in solution. Research with Agr2 d50 will be presented.

CHED 277

Effects of DNA sequence and topology on the binding of heterocyclic diamidine anti-parasitic agents to DNA examined by restriction enzyme activity assays

Cassandra J. Winkle1,, Stefanie Suarez1, David W. Boykin2, W. David Wilson2, Stephen A. Winkle1.  (1) Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States  (2) Department of Chemistry, Georgia State University, Atlanta, Georgia 30302, United States

Heterocyclic diamidines have been shown to have anti-parasitic properties. Previous studies have suggested that these compounds may exhibit sequence selectivity. To further elucidate the effect of DNA sequence and topology on the binding properties of heterocyclic diamidines, restriction enzyme activity assays were performed with a mix of supercoiled and relaxed circular phiX174RF DNAs and the compounds DB75, DB293, and DB818. Drug to base pair ratios ranged from 0.2 to 7.8 drug/base pair. The results indicate that altering drug structure leads to sequence and topological specificity in the binding. Drug effects were shown to vary depending on whether the substrate DNA was relaxed or supercoiled. With DB818, cleavage by Pst I (CTGCAG) showed partial enhancement with relaxed DNA and partial inhibition with supercoiled DNA. Together, these results further delineate the role of drug structure in the sequence and topological selectivity in the binding of heterocyclic diamidines to DNA.

CHED 278

Retromutagenesis: A novel approach to drug resistance in microorganisms

Michael J. Cargill,, Alicia M. James,, Tina T. Saxowsky.Department of Chemistry, Pacific Lutheran University, Tacoma, WA 98447, United States

In non-dividing cells, such as those subject to drug pressure, the influence of persistent DNA damage on transcription could affect cellular outcomes. Base damage can be bypassed by RNA polymerase, resulting in a pool of mutant mRNAs through transcriptional mutagenesis (TM), and potentially a population of mutant proteins that could alter the phenotype of the cell. We hypothesize that TM could be an important first step in acquiring drug resistance, as the mutant protein could allow cells to resume DNA replication and convert this damage to a permanent advantageous mutation, a process we call retromutagenesis. Using Saccharomyces cerevisiae as a model organism, we have established an experimental system to elucidate this process. Furthermore, we have begun to explore the effects of increasing steady state levels of DNA damage by either compromising repair pathways or inducing additional damage with UV-A irradiation.

CHED 279

Three hair mutations, frizzy (fr), frizzy-like (frzl), and retarded hair growth (rhg), disrupt distinct genes on mouse chromosome 7

Samantha R Hughes,, Thomas R. King.Department of Biomolecular Sciences, Central Connecticut State University, New Britain, CT 06050, United States

The frizzy (fr) mutation has previously been assigned to the Prss8 gene on mouse Chromosome 7. The retarded hair growth (rhg) and frizzy-like (frzl) mutations also generate hair defects and map to the same region as fr, but whether they are alleles of Prss8 or mutations in distinct genes is not known.To discover the genetic relationship among these mutations, I have crossed all pair-wise combinations of these variant mice and have shown that all three mutations complement, and therefore must lie in distinct genes. To identify alternative gene candidates by a positional approach, I have mapped rhg between markers that flank fewer than 25 genes. One of the genes in this interval, Fgfr2, is known to be required for normal hair development. But, since mice carrying both Fgfr2Δ and rhg or Fgfr2Δ and frzl are normal, I conclude that neither of these mutations is a defect in Fgfr2.

CHED 280

Taking back control: Active engagement and enhanced student learning in a guided inquiry biochemistry laboratory course

Jamila Lee,, Nakeya Hudgens,, Candace Timpte, Gillian Rudd.School of Science & Technology, Georgia Gwinnett College, Lawrenceville, GA 30043, United States

This project-based laboratory will become a part of the GGC curriculum as it improves student interest and skills by updating and upgrading the biochemistry laboratory. Students will experience the isolation and purification of cytochrome c in an environment where learning is experiential and steeped in investigation. New learning materials and applications have been developed for the biochemistry laboratory course that include: (i) the preliminary preparation of cytochrome c from a source; (ii) its consequential separation from other proteins using liquid chromatography; (iii) investigating protein assays and applying a standard curve, with construction of a protein purification table; and (iv) estimating the molecular weight of cytochrome c by SDS-PAGE. Pre, post and attitudinal studies will contribute to SoTL. This project will enhance the reality of - and student perception of - how biochemistry is done in the real world.

CHED 281

Antimicrobial cyclic peptoids inducing transmembrane pore formation in Staphylococcus aureus

Peter T Smith,, Mia Huang, Kent Kirshenbaum.Department of Chemistry, New York University, New York, NY 10003, United States

Antimicrobial peptides (AMPs) are a large class of defense molecules in multicellular organisms that exhibit broad and potent activity. We investigated the use of N-substituted glycine oligomers, peptoids, as AMP mimics with similar low concentration antimicrobial activities. The mechanism of action of AMPs varies, but many penetrate bacterial cell membranes leading to leakage and death. Our antimicrobial cyclic peptoids demonstrate a similar pore-formation mechanism against methicillin-resistant Staphylococcus aureus. We observed that the minimum inhibitory concentrations of the peptoids increased with the addition of polyethylene glycol to the cell suspensions, which protected from a loss of osmotic balance. This decrease in antimicrobial activity was more significant with larger osmoprotectants indicating that peptoids formed pores with initial diameters greater than 3.8 nm. Scanning electron microscopy was used to analyze cell membrane damage after 24 hours of peptoid treatment. These images revealed extensive membrane deformities and pores reaching over 200 nm in diameter.

CHED 282

Chemical methods for the detection of cysteine sulfenic acid in biological systems

Travis J Brachtenbach,, Justin M Chalker.Department of Chemistry and Biochemistry, The University of Tulsa, Tulsa, Oklahoma 74104, United States

Regulation of reactive oxygen species is an essential function in cellular health. Disruption in cellular redox regulation is a hallmark of atherosclerosis, cancer, neurodegenerative disease, and aging. Therefore, it is critical to monitor the proteins that maintain redox homeostasis. One such protein residue implicated in cellular redox maintenance is cysteine sulfenic acid. Yet, despite its putative role as a messenger in redox regulation, very few methods exist for its real-time analysis. Of the chemical probes used to detect cysteine sulfenic acid, dimedone is the most widely used reagent. In this report, we disclose an examination of dimedone selectivity and introduce alternative probes for the bioorthogonal detection of cysteine sulfenic acid. Applications in the analysis of oxidative stress are discussed.

CHED 283

Immunotoxic effects of undecafluoro-2-methyl-3-oxahexanoic acid in mouse models

Blake R Rushing1,2,, Jamie DeWitt1.  (1) Department of Pharmacology & Toxicology, Brody School of Medicine at East Carolina University, Greenville, NC 27834, United States  (2) Department of Chemistry, Catawba College, Salisbury, NC 28144, United States

Perfluorinated compounds (PFC) are organic compounds where C-H bonds have been replaced with C-F bonds. A new PFC named undecafluoro-2-methyl-3-oxahexanoic acid (U2M3-OHxA) is a potentially less toxic replacement for current PFCs. Immunotoxicity was tested using C57BL/6 mice that were exposed to 0, 1, 10, and 100 mg/kg of U2M3-OHxA by gavage for 28 days. Body and organ weights were recorded and spleens were used for immunophenotyping. Mice were immunized with sheep red blood cells on day 24 and ELISAs were used to measure the IgM antibody responses. Results showed a loss in body weight for females in the 100 mg/kg group, increased liver weight for 10 and 100 mg/kg doses, increased thymus weight for the 100 mg/kg males, decreased splenic weight for 100 mg/kg females, a decrease in the CD45 (B cell) splenic lymphocytes for males in the 1 and 100 mg/kg dose groups, and no changes in IgM responses.

CHED 284

Antibiotic delivery from electrospun non-woven mats

Caitlin E. Pegg,, Amberleana D. Sweeney, Ruya R. Ozer, Justin M. Chalker.Department of Chemistry and Biochemistry, The University of Tulsa, Tulsa, Oklahoma 74104, United States

Antiobiotics and other pharmaceuticals containing a basic site can be easily conjugated to alginic acid through an acid-base reaction. The resulting polymer can then be used to prepare non-woven mats by electrospinning with a copolymer such as PVA. Presented here is an examination of antibiotic release from these materials by a simple ion exchange pathway and its effectiveness in inhibiting bacterial growth. Applications to wound treatment and pain management are also discussed.

CHED 285

Drug release from electrospun nanofibers by ion exchange: A kinetic analysis

Amberleana D. Sweeney,, Caitlin E. Pegg, Ruya R. Ozer, Justin M. Chalker.Department of Chemistry and Biochemistry, The University of Tulsa, Tulsa, Oklahoma 74104, United States

Basic drugs and drug-like compounds were loaded onto alginic acid through an acid-base reaction. The resulting polymer solution was electrospun with a PVA carrier polymer to provide non-woven mats useful for biomedical applications. Presented here is a kinetic analysis of drug release through an ion exchange mechanism. Application to wound healing is also discussed.

CHED 286

Modified porphyrins for photodynamic therapy of triple-negative breast cancer

Taylor Neeley, nee49224@OBU.EDU, Jospeh E. Bradshaw, Timothy E. Hayes.Department of Chemistry, Ouachita Baptist University, Arkadelphia, AR 71998, United States

Photodynamic therapy (PDT) is a cancer treatment that kills cells using light, but there is a need for improved PDT drugs. An ideal PDT drug exhibits high toxicity at low concentrations in the light while showing low toxicity in the dark. It must be soluble in water but must also demonstrate lipid solubility to cross the cell membrane. Seven new porphyrin derivatives were compared to Foscan as photosensitizers on triple-negative breast cancer cells. All were highly effective below 10 μM but none as low as Foscan, a drug in Stage II clinical trials. All exhibited less dark toxicity than Foscan. The distribution coefficient (logD) and cell uptake were measured for each derivative. No correlation was observed between logD, uptake and the light and dark toxicities. Several of these compounds may be candidates for PDT drugs since they are effective at low concentration but show reduced dark toxicity compared to Foscan.

CHED 287

Synthesis of new RNA bases

Pandora E White1,, Stephen Woski2.  (1) Department of Chemistry and Physics, Alcorn State University, Alcorn State, Mississippi 39096, United States  (2) Department of Chemistry, University of Alabama, Tuscaloosa, AL 35487, United States

Although there has been tons of work done on DNA nucleosides, very little work has been done on RNA nucleosides. The purpose of this experiment was to synthesize a RNA nucleoside with a carbazole base. The results of the experiments are indicative that β-1-(9-carbazolyl)-ribofuranose has been synthesized.

CHED 288

Effects of sodium fluoride binding on the electrochemical properties of heme proteins

Margaret H Roeder,, Danielle N Houchins, Emily J Amendola, Jacquelyn D Castorino, Andrea L Fritz, Carmen X Guzman, Jose F Cerda.Department of Chemistry, Saint Joseph's University, Philadelphia, PA 19131, United States

Heme proteins have a wide range of functions. The reactivity of the heme iron is important in the function of the protein as well as the interaction between the heme cofactor and the surrounding protein. In our research we use fluoride binding to the heme iron to understand the behavior of a heme protein in the oxidized state. We have studied heme proteins such as myoglobin (Mb), hemoglobin (Hb), and horse radish peroxidase (HRP), all of which contain an important distal histidine which plays a specific role in each of these proteins. UV/Vis spectroelectrochemical experiments performed on Mb at various pH show evidence of the protonation of the distal histidine in the heme pocket of the protein with a pKa of 5.7. Moreover, pH dependence of fluoride binding to Mb, Hb, and HRP demonstrate ionization of the distal histidine in Mb and Hb, but not in HRP.

CHED 289

jhp1130 from ​H. pylori​ J99 is a HAD phosphatase

Aubree Albert,, Anne Roberts.Chemistry, Western Connecticut State University, Danbury, CT 06810, United States

Helicobacter pylori is a gram-negative bacterium that colonizes the human stomach and causes gastric ulcers. Although the H. pylori genome has been sequenced, the functions of many of H. pylori's genes are not yet known. The gene jhp1130 has been identified as a member of the HaloAcid Dehalogenase (HAD) superfamily. The presence of three conserved sequence motifs indicates that the jhp1130 protein likely functions as a small molecule phosphatase. We have cloned, expressed, and purified the protein and have tested its activity against a variety of small molecule phosphorylated substrates. The goal of this research is to determine the metal ion dependence, pH dependence, and the true in vivo substrate and metabolic function of the jhp1130 enzyme.

CHED 290

What makes Lyme disease tick? Characterization of an essential global regulator in Borrelia burgdorferi

Elisabeth A Geyer,, Sarah E Evans.Department of Chemistry and Biochemistry, Canisius College, Buffalo, NY 14208, United States

Caused by the bacteria Borrelia burgdorferi, Lyme disease is the fastest growing and most common tick-borne illness in the United States. Vital to the survival of B. burgdorferi in ticks and vertebrates, Borrelia oxidative stress regulator, BosR, is a regulatory transcription factor that functions to activate and repress nearly 80 genes, including genes for DNA protection from damage during starvation or oxidative stress and control over the expression of outer membrane proteins. To-date, little has been discovered about the important role and types of metal ions that are thought to function in the regulatory pathway of BosR. In this work, focus is placed on the preparation, purification and characterization of the protein, as well as initial analysis of BosR by metal binding titrations with UV-Visible spectroscopy. Electromobility shift assays and fluorescence anisotropy assays are also analyzed to investigate DNA binding properties and possible classification of a Bos box.

CHED 291

Metabolic regulation of terpenoid biosynthesis in rhodospirillum rubrum

Brittany Hemelgarn,, Francis Mann.Department of Chemistry, Winona State University, Winona, MN 55987, United States

Rhodospirillum rubrum is a bacterium that has the metabolic versatility to produce energy through four different pathways: fermentation, photosynthesis, nitrogen-fixation and cellular respiration.R. rubrum can synthesize terpenoids that are utilized in energy production and other cellular functions. Different terpenoids are produced depending on what energy the environment provides which indicates that the biosynthetic gene expression differs in different metabolic conditions. Only four non-carotenoid synthase terpenoid biosynthetic genes exist in the R. rubrum genome. Our goal is to study the function and expression of these genes that are involved with the biosynthesis of terpenoids. Understanding the metabolic process of R. rubrum will assist in improving the efficiency of modern-day cyanobacteria and lower the cost of engineered molecules.

CHED 292

Determination of lachesin as a cell surface receptor protein for flock house virus using gateway cloning in Saccharomyce cerevisiae

Jason Blanks,, Amy Odegard.Department of Chemistry, University of Puget Sound, Tacoma, WA 98406, United States

The simplicity of the Flock House virus (FHV) capsid and genome, along with the wealth of available structural information, make FHV an excellent model system for studying viral infection. Lachesin, a receptor protein in Drosophila, has been proposed as the receptor protein required for FHV to infect Drosophila. Still, no conclusive evidence demonstrating FHV binging to lachesin has been presented. In my research, I will use Gateway cloning to demonstrate that a) lachesin does bind FHV and b) lachesin is necessary for FHV infection. Once the receptor protein for FHV is determined, the interactions between FHV and the receptor can be characterized. This will lead to a better understanding of how FHV and other non-enveloped viruses, that cause serious human disease, infect host cells.

CHED 293

Evidence for the role of a novel histone mark in hippocampal neurogenesis

Anna Weinstein1,2,, Miriam E.R. Baker2, Christina M. Hughes3, David Allis3, Bruce S. McEwen2, Richard G. Hunter2.  (1) Stern College for Women, Yeshiva University, New York, NY 10016, United States  (2) Laboratory of Neuroendocrinology, The Rockefeller University, New York, NY 10065, United States  (3) Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10065, United States

Epigenetics is the study of processes that regulate gene expression without altering the actual DNA sequence. Entailed in such processes are various modifications, which impact the genome while preserving nucleotide sequence. Since epigenetic information is often contingent on something as transient as stress, it is said to be susceptible to environmental conditions, making it an important link in broadening our understanding of how the environment impacts physiological function. Studies have shown that stress decreases neurogenesis in the hippocampal region. In order to examine the effects of chronic stress on the putative mitotic histone mark H3 Serine 57 phos (H3S57p), we performed a series of Light Immunocytochemistry (ICC) protocols on hippocampal sections from wild type and stressed mice. The results so far indicated a lower level of the H3S57p mark in the stressed hippocampal sections, indicating the possibility that it is indeed a mitotic marker affected by chronic restraint stress.

CHED 294

Comparison of breast cancer and osteosarcoma secretomes and lysates using LC-MS/MS

Crystal L Daniels1,2,, Lewis K Pannell2.  (1) Spring Hill College, Mobile, AL 36608, United States  (2) Mitchell Cancer Institute, University of South Alabama, Mobile, Al 36604, United States

A study of the secreted proteins, the secretome, can provide insight into what proteins are functioning in the microenvironment of a cell. Secretome studies have the potential to identify more specific biomarkers than that of serum protein studies, due to the proximity of the sample. Secreted proteins are present in relatively low abundances and are easily masked by cytosolic and serum proteins. Secretome isolation is vital for using the secretome as a source for biomarker discovery. Comparison of secretomes to lysates helps to assess the effectiveness of the collection method at limiting protein contamination. MBA-MD-231Her2 secretome analyses revealed that approximately 56% of the proteins identified were secreted via the non-classical or classical method. Comparatively, 52% of proteins were identified as being secreted by the U2OS cell line. The method used was effective in isolating the secreted proteins and limiting the amount of intracellular and serum protein contamination.

CHED 295

Species and growth optimization of algal biofuel feedstocks

Brynn Umbach,, Erin Gehlhausen, Charles R. Sweet.Department of Chemistry, United States Naval Academy, Annapolis, MD 21402, United States

To develop algal feedstocks with enhanced biofuels potential, we examined the lipid content of extremophilic algae, including novel strains isolated by winter bioprospecting of the Chesapeake Bay. To assess the potential of these algae, we examined them in comparison to the model organism Chlorella. The algal fatty acid profiles, characterized from hydrophobic Bligh-Dyer extracts by FAME (fatty acid methyl ester) GC-MS, show similarities to other algae but also significant differences which may result in favorable fuel characteristics. These differences include an unusual acyl population in the acidothermophile Galdieria sulphuraria, which contains unsaturated and polyunsaturated 20-carbon fatty acids. In addition we have compared the lipid content of these organisms under a variety of growth conditions and lipid isolation techniques, and have also used MALDI-TOF mass spectrometry to examine the total lipid composition of these algae and gain a more comprehensive understanding of their lipid content.

CHED 296

Analysis of volatile organic compounds in the desert shrub Larrea tridentata (creosote bush)

Luis Alcala,, Mary A. Kopecki-Fjetland.Department of Chemistry, St. Edward's University, Austin, TX 78610, United States

Larrea tridentata, creosote bush, is a desert shrub found in dry, arid regions of North America, and the most common desert shrub in the Southwest. This drought resistant woody perennial becomes part of the main source of food for mammalian herbivores during the dry season. The leaves and berries of L. tridentata produce and emit phytogenic volatile organic compounds (PVOC) which may have an effect on the grazing patterns of desert herbivore populations. This research aims to analyze the exact PVOC profile of L. tridentata. To date identified PVOCs include limonene, camphor, alpha-cedrene, AR-curcumene and (E)-nerolidol. Current research is focusing on identifying additional PVOCs contained in L. tridentata using sold-phase microextraction (SPME), gas chromatography-mass spectrometry, and retention indices.

CHED 297

Black band disease (BBD): Pigment characterization and reactive oxygen species (ROS) production and evolution assay development

Kymberlee A Osborne1,, Kathleen Rein1, Miroslav Gantar2, Martin Quirke1, Ian Campa3, Laurie Richardson2.  (1) Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States  (2) Department of Biology, Florida International University, Miami, Florida 33199, United States  (3) Department of Chemistry, Columbia University, New York, New York 10027, United States

Reefs are integral to world economies contributing to food sources and tourism of coastal communities, serving as nurseries and habitats for marine life, and as a source of oceanic photosynthetic activity. Black band disease (BBD) is a cyanobacterial dominated polymicrobal disease, killing framework building coral. This investigation focused on characterizing major pigments of some BBD cyanobacteria, including identifying and quantifying pigments contributing to the dark, or black, appearance of BBD. BBD cyanobacterial pigments identified were compared with that found in non-BBD cyanobacterial strains. Additionally, we investigate the production of reactive oxygen species (ROS) by BBD cyanobacteria. Pigment analysis points to chlorophyll a, pheopytin a, phycocyanin, and phycoerythrin. Since some photosensitize, cells exposed to solar irradiation should produce and excrete ROS. Initial ROS analysis indicates that cellular ROS production and evolution occurs at a higher rate in cyanobacterial cells that have been subjected to solar irradiation relative to dark controls.

CHED 298

Detection of caspase 3 activity in Chinese hamster ovarian cells after treatmeant with Morinda citrifolia (Noni) extract

Nicole M. Yordán-López,, Lizette Santos-Santori.Department of Chemistry, Pontifical Catholic University of Puerto Rico, Ponce, Puerto Rico 00717, Puerto Rico

Apoptosis is a genetically controlled process by which a cell dies naturally. It is initiated through activation of effector Caspases 3/7. Morinda citrifolia is used as a dietetic supplement because of its antioxidant, anti-inflammatory and hepatoprotective properties. Noni shell extracts, aqueous and organic, and pulp extract were prepared. CHO cells were cultured. After treatment with the plant's extracts for a 96-hour period, a colorimetric substrate was applied and incubated for four hours at 37ºC. Absorbance measurements were determined. Preliminary results were 0.00050 pmol/µL for pulp, 0.00480 pmol/µL aqueous extract, and 0.0100 pmol/µL for organic extract. Results suggest organic extract from Noni shell had and inductive effect on Caspase 3 activity. Other assays will be conducted to verify these results and establish specific conclusions.

CHED 299

DNA phosphate crowding correlates with protein cationic side chain density and helical curvature in protein/DNA crystal structures

Bryce Grant, Jayme Arameda, JARANEDA1@CUB.UCA.EDU, Madison Throneberry, MTHRONEBERRY1@CUB.UCA.EDU, Elizabeth Dourlain, Lori Isom.Department of Chemistry, University of Central Arkansas, Conway, AR 72035, United States

DNA flexibility is crucial in many biological functions including protein/DNA recognition, gene transcription, and DNA packaging inside the cell. This project investigated the indirect readout relationship between cation-induced phosphate collapse and DNA bending. Phosphate crowding around high density cationic protein residues in protein/DNA complexes was considered. In this project, crystal structures of protein/DNA complexes with resolution of 2.5Å or higher were selected from the PDB. Structures containing DNA breaks and modified bases were excluded. Each structure matching the criteria was then analyzed and assigned two crowding functions for each phosphate oxygen: one quantifying each phosphate's crowding with respect to other phosphates and one quantifying the cation density. The correlation between phosphate crowding and cation density was calculated for each structure and compared to the type of DNA distortion present in the complex.

CHED 300

Deletion of the yhfR gene in Bacillus subtilis and its effects on isoprene and methylbutanol production

Tyler S Beyett,, Tami L Sivy.Department of Chemistry, Saginaw Valley State University, University Center, MI 48710, United States

Isoprenoids are produced via the mevalonic acid (MVA) and methylerythritol phosphate (MEP) pathways and are among the most valuable secondary metabolites. Isoprenoids with medicinal value have proven extremely difficult to synthesize and microbial production has been complicated due to cell death as a result of the buildup of toxic precursors in engineered cells. Bacillus subtilis exhibits a greater tolerance towards these toxic precursors than E. coli, possibly due to the presence of the yhfR gene, whose enzymatic product is thought to be responsible the detoxification of pathway intermediates. We replaced the yhfR gene with a spectinomycin resistance cassette, confirmed by qPCR and sequencing, and have analyzed methylbutanol and isoprene production in engineered and wild-type cells. Our research aims to determine whether the enzyme coded for by yhfR plays a role in the conversion of toxic precursors to volatile compounds that can be released into the environment.

CHED 301

Comparison of coralsnake venom components between individuals

Sloane Zimmerman,, Randall A. Kopper.Department of Chemistry, Hendrix College, Conway, AR 72032, United States

Snakes utilize their venom, a mixture of multiple proteins and enzymes, for protection and prey acquisition. One of the most toxic enzymes found in coralsnakevenom is phospholipase A2. In order to investigate the variation in venom composition between individual coralsnakes, venom samples from 13 coralsnakes were analyzed for total protein concentration, their electrophoretic protein profile, and their specific phospholipase A2 enzyme activity. Most previous studies of venom components have been performed using pooled samples comprised of venom from multiple individuals. While using pooled venom provides a larger volume of sample to work with, it masks individual variances. This analysis of venom from 13 coralsnakes demonstrates the differences between individuals of this species. Preliminary results indicate a significant inverse relationship between venom volume and total protein concentration. Although the electrophoretic profiles appear similar, the specific enzyme activities vary dramatically.

CHED 302

Metal ion cofactor requirements for phospholipase A2

Jessica Hook,, Randall A. Kopper.Department of Chemistry, Hendrix College, Conway, AR 72032, United States

Phospholipase A2 is an enzyme that hydrolyzes glycerophospholipids, cleaving free fatty acids from the second carbon on the glycerol molecule. Phospholipase is the main contributor to the neurotoxicity of snake venoms, such as coralsnake venom. In its native form, the phospholipase A2 holoenzyme contains calcium as the divalent metal ion cofactor. In this study, the endogenous calcium ion was removed and other divalent metals were tested as possible replacements for calcium. Various metals were tested for their ability to function as a replacement cofactor to activate the enzyme and for their binding affinity in comparison to calcium. The chelating agent EDTA was used to sequester the calcium from phospholipase A2, allowing their replacement with other divalent metals. The results of the study will reveal whether metals other than calcium can active the enzyme, and through binding competition studies indicate the relative binding affinity of the enzyme for various metal ions.

CHED 303

Adsorption of snake venom proteins by activated charcoal

Olivia R. Urbanowicz,, Randall A. Kopper.Department of Chemistry, Hendrix College, Conway, AR 72032, United States

Over 7,000 people receive venomous snakebites in the United States each year; one in five of those are from rattlesnakes. The Diamond-Backed Rattlesnake (C. atrox) venom contains hydrolytic enzymes including proteases and phospholipase A2 that produce severe symptoms such as necrosis and paralysis and may be fatal if not treated quickly. Activated charcoal is currently the most common emergency treatment for ingested poisons. This study investigates the use of activated charcoal for the adsorption of rattlesnake venom proteins to reduce hydrolytic enzyme activity. Venom samples were incubated with increasing amounts of activated charcoal and then centrifuged to remove the charcoal. The resulting solutions were analyzed by gel electrophoresis, total protein determination and enzyme activity assay. The results will determine the efficacy of using activated charcoal as a potential treatment option for snakebites before emergency medical care is available.

CHED 304

Visualizing the effects of mutations in Scytovirin

Charity Haggenmaker,, Robert L. McFeeters.Department of Chemistry, University of Alabama in Huntsville, Huntsville, Alabama 35899, United States

The carbohydrate binding protein Scytovirin acts as an antiviral entry inhibitor. Structural engineering has been used to improve Scytovirin's ability to protect against the HIV-1 infection. 15N-HSQC spectra for Scytovirin and eleven mutant forms were analyzed. The changes in chemical shift caused by mutating one amino acid were mapped onto the structure. Resonances were assigned by inspection and categorized by the magnitude of the chemical shift change. It was determined that mutations in various regions were more likely to affect the protein core than others. Overall, Scytovirin is structurally resistant to amino acid changes, opening the possibility of structural engineering to reduce cost and increase efficacy.

CHED 305

Putative Rhodospirillum rubrum squalene hopene cyclase (A0062) characterization

Kevin L Vickerman,, Francis M Mann.Department of Chemistry, Winona State University, Winona, Minnesota 55987, United States

Rhodospirillum rubrum terpene synthase (Rru_A0062) has an unclear function and activity. Commonly present in bacteria, squalene cyclase converts squalene a triterpene into a hopanoid. Isoagathenediol a cyclized diterpene component in R. rubrum membrane is potentially converted from the same synthase. The lack of analysis of the putative Rhodospirlillum rubrum squalene hopene cyclase (RrSHC) in Rhodospirillum rubrum ATCC 11170 is the reason for our examination of the bioactivity. RrSHC putative dual function as a diterpene and triterpene synthase has not been previously demonstrated. For our examination we utilized cloning and expression RrSHC in Escherichia coli. The activity of RrSHC was approached with crude lysed cells analyzed with GC-MS to track product formation in the presence of either geranylgeranyl pyrophosphate or squalene. A more detailed analysis was attempted on the purified protein. In this analysis, we cloned, expressed, purified, and determined enzymatic parameters of the putative squalene hopene cyclase from Rhodospirillum rubrum.

CHED 306

Studies of mTOR and its substrates in Kirsten virus-transformed murine fibroblasts

Carolina Mendoza,, Kerry Bruns.Department of Chemistry and Biochemistry, Southwestern University, Georgetown, Texas 78627, United States

The mTOR signal transduction pathway in Kristen virus-transformed murine embryonic fibroblast (KBalb) was studied. Regulatory proteins and phosphoproteins associated with this pathway were identified in different cell fractions and compared to the levels detected in the parental cell line (Balb 3T3). In KBalb cells, mTOR and its regulatory proteins (Rictor, Raptor, and GβL) appeared to be present at higher levels than Balb 3T3 cells. These regulatory proteins are important in mTOR's interaction with downstream targets. Sites on mTOR phosphorylated by Akt also appeared to be different between the two cell lines. Rictor-mTOR complex phosphorylates Akt at Serine 473, which is necessary for the phosphorylation of Akt at Threonine 308 by PDK1 and its full activation. The increased levels of Rictor and mTOR proteins and the increased phosphorylation of Akt at Serine 473 and Threonine 308 support this idea that mTOR is more active in K-ras transformed cells.

CHED 307

Molecular mechanisms underlying the function of the cancer-associated protein, NURP1: A computational biochemistry study

Raul Urrutia1, Gabriel Velez1,2,, Marisa Lin1, Gwen Lomberk1, Jose Luis Neira3, Juan Iovanna4.  (1) Translational Epigenomics Program, Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota 55902, United States  (2) Department of Chemistry, Winona State University, Winona, Minnesota 55987, United States  (3) Cell and Molecular Biology Institute Miguel Hernández, Elche University, Alicante, Spain  (4) Cancer Research Center of Marseille, Institute Paoli-Calmettes, Aix-Marseille University, Marseille, France

NURP1 is protein that plays critical roles in cancer development, progression, and resistance to therapy. Its mechanism of action is postulated to rely on its ability to undergo cytoplasmic-to-nuclear translocation, bind DNA and regulate gene expression. NURP1 binds to DNA in vitro and regulates gene expression networks in vivo. This data has guided efforts to solve the structure of DNA-bound NURP1 in order to develop models to guide the design of drug inhibitors. Previous studies have suggested that NURP1 may be a member of the High Mobility Group of chromatin proteins, but have not provided a model of the NURP1-DNA complex. Here we report the first structural models for both the large and small form of NURP1. Our results show that NURP1s share characteristics yet are distinct from their closely related homolog. These models should be taken into consideration when designing small drugs aimed at controlling the function of NURP1s.

CHED 308

Effect of Morinda citrifolia on the erythromicyn-N-demethylase and cytochrome P450 activity

Maria del Mar Morales1,, Lizette Santos-Santori2.  (1) Deparment of General Science, Pontifical Catholic University of Puerto Rico, Ponce, Puerto Rico 00717, Puerto Rico  (2) Deparment of Chemistry, Pontifical Catholic University of Puerto Rico, Ponce, Puerto Rico 00717, Puerto Rico

Morinda Citrifolia also known as Noni has a long history of use as a medicinal plant because of its antioxidant, anti-inflamatory and hepatoprotective properties. To determine Noni effect in Cytochrome P450 isoenzymes, aqueous and organic extractions from the seeds and the skin were prepared. Extracts were analyzed by HPLC. CHO cells were treated for 48 hours. Microsomes were prepared. Protein and erythromicyn-N-demethylase assays were perfomed. Enzyme activity was determined to establish the effect of Noni in the system. Results showed a low concentration of protein in the experimental groups: 0.0306µg/ml (pulp), 0.0306µg/ml (aquous skin extract) and 0.0305 µg/ml (organic skin extract). Results from the erythromicyn-N- demethylase assay showed no activity. Results suggest a decrease in activity.

CHED 309

Structural and functional determination of the polysaccharide deacetylase BC0361

Elitsa I Stoyanova,, Kathryn E Cole.Department of Chemistry and Biochemistry, Ithaca College, Ithaca, New York 14850, United States

The gene bc0361 encodes for a polysaccharide deacetylase, which is part of the carbohydrate esterase family 4 (CE 4). All members of this family share a conserved (α/β)8 barrel fold and a divalent metal ion (most commonly zinc) associated with the active site. This particular enzyme helps bacterial cells become “invisible” by removing the acetyl groups from membrane sugars, which are recognized by the host immune macrophages. Inhibition of this enzyme would disable the defensive mechanisms of the bacteria, which is a possible route for antibiotic drug development. Crystals of the native protein have been obtained, and crystallization of enzyme-inhibitor complexes is currently in progress.

CHED 310

Structural elucidation of histone deactylase 8 with "linkerless" hydroxamic acid inhibitors

Rochelle J. Frankson,, Kathryn Cole.Department of Chemistry and Biochemistry, Ithaca College, Ithaca, NY 14850, United States

Histone deacetylases (HDACs) catalyze the deacetylation of both histone and non-histone proteins. The catalysis of this reaction is critical to many cellular processes such as cell differentiation, senescence, and apoptosis. As such, aberrant HDAC activity is linked to the proliferation of certain diseases such as cancer, validating the use of histone deacetylase enzymes as targets for drug design. Two HDAC inhibitors, suberoylanilide hydroxamic acid (SAHA), and Romidepsin have already been approved for use as cancer chemotherapy agents while several others are under clinical trial. Numerous small molecules have been developed to inhibit HDAC8. Included in this array are 'linkerless' hydroxamic acids that present potencies on the micromolar scale (IC50: 0.3 mM – 66.0 mM). Here, we report the findings of the enzyme-inhibitor structural investigation of six of these hydroxamic acid inhibitors.

CHED 311

Small molecules as potential regulators of quorum sensing

Nicholas Dragotakes,, Emily Garcia Sega.Department of Chemistry, Ithaca College, Ithaca, New York 14850, United States

Quorum sensing (QS) is a population-density dependent form of inter-cellular bacterial communication. Pseudomonas aeruginosa uses QS to coordinate pathogenic aggression against hosts whose immune systems have already been compromised. The natural acyl homoserine lactone (AHL) autoinducer of P. aeruginosa binds to the LasR receptor, activating transcription of virulence genes. Variations within the acyl chain of AHL autoinducers has been extensively researched. Recently, a triphenyl scaffold, which is structurally unrelated to the natural AHL autoinducer, has shown binding capability to LasR. We sought to design new QS regulators which incorporate modifications of both the triphenyl and acyl substituted scaffolds. The synthesis of these compounds takes advantage of a modular synthetic route and aims to further explore the interactions within the LasR ligand binding domain. Synthesized compounds are then analyzed for QS regulation in a LasR GFP reporter assay.

CHED 312

Identifying proteins that bind to UBE2Q2 and exosome component 7

Crista E. Riggs1,, Kimberly Hammock2, David F. Crawford2.  (1) Department of Chemistry, Ouachita Baptist University, Arkadelphia, AR 71998, United States  (2) Department of Pediatric Hematology and Oncology, University of Oklahoma School of Medicine, Oklahoma City, OK 73104, United States

Proteins that regulate mitotic checkpoint function are highly important in cancer research. Mitotic checkpoints are essential to normal cell cycle regulation, and they allow cells to correct threats to genomic integrity in order to decrease the risk of developing malignancies. UBE2Q2 is an ubiquitin-conjugating enzyme that is thought to antagonize an early mitotic checkpoint in HeLa cells. It is predicted that UBE2Q2 over-expression promotes the development of malignancies. When the expression of UBE2Q2 is inhibited, cells become more sensitive to treatment with chemotherapy agents and become suspended in prometaphase, causing apoptosis to occur. Previous studies concluded that another protein, Exosome Component 7 (ExoC7), interacts with UBE2Q2. Both epitope-tagged UBE2Q2 and ExoC7 were expressed and affinity purified, and putative UBE2Q2- and ExoC7-binding proteins were found. These proteins could be essential to developing new cancer therapy drugs and useful for better understanding the role of mitotic checkpoint function in cancer.

CHED 313

Effect of chironja on cytochrome P450 system of CHO cells

Natalia S Fernández Dávila1,, Lizette Santos2.  (1) Department of Biology, Pontifical Catholic University of Puerto Rico, Ponce, Puerto Rico 00717, Puerto Rico  (2) Department of Chemistry, Pontifical Catholic University of Puerto Rico, Ponce, Puerto Rico 00717, Puerto Rico

Previous investigations agree that different isoenzymes from the Cytochrome P450 System can be affected by a variety of compounds present in grapefruit. 'Chironja', being a hybrid between orange and grapefruit, can probably interact with the Cytochrome P450 System. Extractions from the fruit and the skin were performed. The extracts were analyzed by HPLC and CHO cells were treated for 48 hours with the chironjas' extracts. Microsomes for each group were prepared. Protein and erythromycin N-demethylase assays were performed. Protein concentration and ERDN activity were higher in the sample treated with the aqueous extract with values of 0.0401µg/ml and 3.399nmol/min/mg respectively. Further studies are being conducted in order to establish the effect of the different Chironja's extracts on the isoenzymes.

CHED 314

Exploring cutting edge biotechnology: A cloning blueprint of serine carboxypeptidase II

Perouza Parsamian,, Mary A. Kopecki-Fjetland.Department of Chemistry, St. Edward's University, Austin, TX 78704, United States

Serine Carboxypeptidase II (SCP) is a proteolytic enzyme that cleaves the C-terminal residue of polypeptides and is primarily found in species of yeast, more specifically Sacchromyces cerevisiae. SCP contains a catalytic triad consisting of histidine, aspartate, and serine. A similar enzyme, Serine Endopeptidase, cleaves within the polypeptide through a catalytic triad analogous to that of SCP. An association to both structures of enzymes and an alteration to their functions suggest an example of convergent evolution. To determine this evolutionary phenomenon between two catalytic enzymes, kinetic studies need to be conducted. SCP from S. cerevisiae was amplified and ligated into the pGEM-T nonexpression vector. SCP was then reisolated and ligated into the pET-32C vector. Currently potential clones are being analyzed for the presence of the SCP gene using restriction endonucleases and sequencing. Future work includes purification of the fusion protein followed by kinetic studies.

CHED 315

Evaluation of the role of disulfide crosslinkages in lysyl oxidase via site-directed mutagenesis

Megan A. Smith,, Karlo M. Lopez.Department of Chemistry, California State University, Bakersfield, Bakersfield, CA 93311, United States

Lysyl oxidase is a copper-dependent amine oxidase that plays an important role in catalyzing the oxidation of amino groups in the proteins, collagen and elastin. The catalyzed process results in aldehyde molecules, which is essential in the production of the crosslinkages in these proteins. There are few studies involving the use of native lysyl oxidase from bovina aorta, which provides structural properties, specifically the connectivity of the five-disulfide linkages. The main focus of this study is to investigate the role each disulfide bond has on lysyl oxidase. A LOX mutant, C238S, was generated via PCR mutagenesis program. Overexpression of this mutant yielded 16.01mg of enzyme per liter of media. Total copper incorporation is currently being calculated. There was no catalytic activity for this mutant when compared to the wildtype. A redox cycling assay was performed, which confirms that a quinone is present even when one disulfide linkage was removed.

CHED 316

Overexpression and characterization of NusA tagged lysyl oxidase

Madison A Smith,, Karlo M. Lopez.Department of Chemistry, California State University, Bakersfield, Bakersfield, CA 93311, United States

Lysyl oxidase is a copper-dependent enzyme that plays an important role in the cross linkages on elastin and collagen in connective tissues and other biological systems. The crystal structure of LOX has never been observed mainly due to the low solubility of the enzyme and the high levels of urea required to solubilize the enzyme. Crystallography cannot be accomplished if urea is present because the concentration of urea is much greater than that of the enzyme. To increase the solubility of LOX without the use of urea, the enzyme was co-expressed with a NusA solubility tag and purified using an aqueous buffer with the absence of urea. Overexpression of this enzyme with the solubility tag yielded 2.7mg of protein per liter of media. Total copper incorporation was calculated to be 68%. Average specific catalytic activity was calculated to be 0.1065 units/mg of enzyme.

CHED 317

Model for small heat shock protein inhibition of polyglutamine aggregation

Carley Little,, Eamonn Healy.Department of Chemistry and Biochemistry, St. Edward's University, Austin, TX 78704, United States

The polyglutamine (polyQ) repeat disease family is a CAG trinucleotide repeat expansion in the protein-coding region that results in expression of an expanded polyQ domain. Huntington's disease and the spinocerebellar ataxias (SCAs) are within this family, where polyQ expansion leads to the formation of fibrillar protein aggregates, causing neuronal cell death. With a threshold exceeding 52 glutamines, ataxin-3, the causative agent of SCA3, triggers formation of intranuclear aggregates. αB-crystallin is a small heat shock protein that suppresses SCA3 toxicity, likely by forming a transient aB-crystallin/ataxin-3 complex. After performing extensive simulations of the interaction of human αB-crystallin and ataxin-3, we predicted an energy-preferred complex; the bioactive peptides FSVN and HEER were identified through analyzing solvent-accessible backbone hydrogen bonds. Using AutoDock to run docking simulations, it was found that FSVN and HEER complexed with the ataxin-3 much like the human αB-crystallin/ataxin-3 complex, implicating the formation of a weak yet effective transient complex.

CHED 318

Heme loss in myoglobin and hemoglobin in the presence of fluoride

Danielle N Houchins,, Brady O Werkheiser,, Margaret H Roeder, Katherine C McGovern, Victoria C Angelucci, Jose F Cerda.Department of Chemistry, Saint Joseph's University, Philadelphia, PA 19131, United States

Myoglobin (Mb) and hemoglobin (Hb) have very similar roles in that both proteins bind oxygen. The heme-bound oxygen is stabilized through hydrogen bonding from the distal protonated histidine. We have recently used fluoride ion in our research to understand the role of the distal histidine in the ferric state of heme proteins. Our study at various pH shows that the heme-bound protein to heme loss transitions in ferric Mb and Hb occur at a pKa of 4.5. However, in the presence of fluoride ion, the heme loss transitions in both of these proteins are shifted to a pKa of 4.2. This shows that the heme-bound fluoride stabilizes the ferric state by being a better hydrogen acceptor than the water ligand.

CHED 319


CHED 320

Staphylococcus aureus putative GcpMB protease can cleave specific host tissues and proteins

Gabriel Spencer1,, Marsalis Brown1, Brianna Moncur1, Conwin Vanterpool1, Kenneth LaiHing2, Elaine Vanterpool1.  (1) Department of Biological Sciences, Oakwood University, Huntsville, Alabama 35896, United States  (2) Department of Chemistry, Oakwood University, Huntsville, Alabama 35896, United States

Staphylococcus aureus infections have been a growing concern in the medical community. Some strains of S. aureus are becoming resistant to treatment resulting in fatalities. Thus, it is imperative that we identify the mechanisms utilized by S. aureus to induce host damage. In this study, we have identified, cloned, and expressed a putative Gcp protease of S. aureus. We hypothesize that GcpMB may be associated with virulence of S. aureus. Purified rGcpMB was incubated with homogenized Fisher 344 rat cardiac, gingival and brain tissues. In addition, rGcpMB was incubated with collagen, elastin and asioalofetuin. rGcpMB is shown to selectively degrade host gingival epithelium and cardiac tissues. rGcpMB also degrades/cleaves collagen. Asialofetuin and brain tissue samples were not degraded or cleaved by rGcpMB. In conclusion, data from our lab suggests that this putative protease may be associated with virulence of the organism by selectively degrading host proteins.

CHED 321

Putative GcpMB can interact with virulence factors of Staphylococcus aureus

Ashlea Hendrickson1,, Gabriel Spencer1, Marsalis Brown1, Brianna Moncur1, Kenneth LaiHing2, Elaine Vanterpool1.  (1) Department of Biological Sciences, Oakwood University, Huntsville, Alabama 35896, United States  (2) Department of Chemistry, Oakwood University, Huntsville, Alabama 35896, United States

Methicillin-Resistant Staphylococcus aureus (MRSA) infections have been incurable by many antibiotics. It is imperative that we elucidate the virulence mechanisms of S. aureus. The virulence factors are capable of causing damage to the host. Other factors such as chaperones may be needed to assist in host invasion. Previously, we hypothesize that the putative protease GcpMB may be involved in virulence. The purpose of this study is to identify the mechanisms of GcpMB and their possible associations with the virulence factors of S. aureus. Protein interaction studies and immunoblot analysis show that rGcpMB physically interacts with the serine protease/chaperone HtrA and cysteine protease ScpA of S. aureus. This suggests that GcpMB may share a common pathway with the virulence factors of S. aureus. In conclusion, GcpMB may be involved in the production, processing or maturation of important S. aureus virulence factors.

CHED 322

Effect of TCDD on gene expression of estrogen synthesis enzyme aromatase using real time qPCR

Elizabeth F Ebensperger,, Gregory T Marks.Department of Chemistry and Biochemistry, Carroll University, Waukesha, WI 53186-5518, United States

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a manmade environmental contaminant that is produced during the synthesis of chlorophenols, which are used in herbicides and fungicides. TCDD is an endocrine disruptor that can affect the reproductive system and has been reported to have both estrogenic and anti-estrogenic effects. Estrogens are important hormones that are responsible for sexual development in females and are members of the steroid hormones family. Recent studies show that TCDD's effects start in the ovary, reducing fertility, impairing ovulation, and causing anatomical defects that are not yet fully understood. Female human granulosa cells dosed with TCDD were studied using real time quantitative polymerase chain reaction (RT-qPCR) to determine if levels of aromatase expression, an enzyme key to the estrogen synthesis pathway, relative to the housekeeping gene ribosomal protein L13 (RPL13) were affected and are contributing to the disruption of the female human reproductive system.

CHED 323

Effects of ajulemic acid on VEGF production: Relevance to angiogenic potential in Ewing's sarcoma

Ryan K. James1,, Elizabeth Blankenship1, Amy Eubanks1, Rob J. Griffin2, Lori L. Hensley1.  (1) Department of BIology, Ouachita Baptist University, Arkadelphia, AR 71998, United States  (2) Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States

Ewing's Sarcoma is an aggressive pediatric bone cancer common in teenagers and young adults. It is potentially the most lethal of all bone tumors with a 30% survival rate. Ajulemic Acid (AJA) offers a potential solution to this problem. Our data show this compound successfully kills Ewing's sarcoma cells as well as several other pediatric tumor cell lines in vitro, and we have seen complete tumor regression in approximately 33% of our treated mice. Our data demonstrate that ajulemic acid inhibits the migration of tumor cells and endothelial cells, the cells that line blood vessels and direct their growth. Our aim for this study is to determine the mechanism through which AJA inhibits angiogenesis by looking specifically at its effects on Vascular Endothelial Growth Factor (VEGF) levels. VEGF is a protein secreted by cells to promote angiogenesis, our hypothesis was VEGF is to be inhibited by AJA.

CHED 324

Increasing the permeability of Burkholderia cenocepacia by inserting targeted genomic mutations

Tyler Y Miyawaki,, Kimberly M Specht.Department of Chemistry and Biochemistry, Denison University, Granville, OH 43023, United States

Burkholderia cenocepacia is a multi-drug resistant, opportunistic pathogen infecting those with Cystic Fibrosis and immunocompromised individuals. The membrane is fairly impermeable partially due to a barrier formed by a lipopolysaccharide (LPS) layer on the outer-membrane, localized by the protein BCAL0894. In order to increase the permeability of the outer-membrane, our lab is investigating several different BCAL0894 gene mutations while decreasing the expression of wild-type protein, with the goal of decreasing the overall activity of BCAL0894. Decreased activity of BCAL0894 should localize less LPS in the outer-membrane, creating a more permeable membrane for antibiotic susceptibility. We are now engineering B. cenocepacia strains that each carry a different BCAL0894 gene mutation inserted into the genome utilizing homologous recombination to test for increased permeability.

CHED 325

Gene knockout of an outer membrane protein in Burkholderia cenocepacia

Linda M Weber,, Kimberly M Specht.Department of Chemistry and Biochemistry, Denison University, Granville, OH 43023, United States

Burkholderia cenocepacia is a bacterial strain responsible for causing infections in the lungs of cystic fibrosis patients. This Gram-negative strain is multi-drug resistant with a highly impermeable outer membrane. The impermeability of Gram-negative bacteria is due in part to a high concentration of lipopolysaccharide (LPS) molecules in the outer membrane. Based on sequence homology with similar genes in E. coli, the BCAL0894 gene is expected to play a part in the mechanism responsible for inserting LPS into the outer membrane of B. cenocepacia. Current studies are working towards a gene knockout of BCAL0894, which will determine if the protein is essential for B. cenocepacia viability.

CHED 326

Assessing the effects of spermine on the binding strength of the nucleic acid complexes between polydA+2polyU

Mark Harris, Anne E Serrao, of Biochemistry, Washington & Jefferson College, Washington, PA 15301, United States

In addition to the standard double helix formed by Watson-Crick base-pairs, Hoogsteen base-pairing allows a third strand of DNA or RNA to bind to produce triple helices from different DNA/RNA combinations. Stabilization of nucleic acid triple helices has the potential to be used in the control of gene expression by affecting protein synthesis. This study analyzes the effects of spermine, a polyvalent cation, on the binding strength of the helical complexes formed in a system of two equivalents of polyuridylic acid and one equivalent of polydeoxyadenylic acid. Melting curves show a general trend of increasing stability with increasing spermine concentration. Mixing curves are generated to determine if triple helices had formed or if only double helices were present.

CHED 327

Reversal of RNA toxicity in myotonic dystrophy type 1 using antisense oligonucleotides

Jamie L Platz1,, Rebecca Moore3,2, David Brook2, Christopher Hayes3.  (1) Department of Chemistry & Biochemistry, Carroll University, Waukesha, Wisconsin 53186, United States  (2) Department of Genetics, University of Nottingham, Nottingham, United Kingdom  (3) Department of Chemistry, University of Nottingham, Nottingham, United Kingdom

Myotonic dystrophy type 1 (DM1) is a genetic disease caused by a triplet CTG expanded repeat in the DMPK gene, which codes for DM protein kinase. The CTG repeat causes an RNA gain-of-function, sequestering muscleblind-like (MBNL) proteins which results in missplicing and pathogenesis. In this study, antisense oligonucleotide (ASO) therapy is employed to block the repeat expansion and reverse RNA toxicity. We used ASO gapmers containing DNA and 2'OMe modified bases for optimal binding affinity and potential RNase H induction. Using DM1 cells to screen ASOs, we have identified a 5-12-4 gapmer that reduces RNA foci in situ. However, immunofluorescence analysis shows no reduction in MBNL protein foci, revealing that RNase H is not effectively cleaving the DNA:RNA hybrids, and that sequestered MBNL protein remains nonfunctional. Therefore, additional nucleotide functionality will need to be further investigated; however our research serves as an important gateway for further ASO therapy in DM1.

CHED 328

Purification of avian riboflavin binding protein for a senior level biochemistry lab

Samantha Saville,, Christina Miller.Department of Chemistry, Computer Science, and Mathmatics, Adams State University, Alamosa, Colorado 81101, United States

Experiments done to improve the isolation of avian riboflavin binding protein from chicken egg yolk will be discussed. The protein was purified by salting out, dialysis, and ion exchange chromatography. Characterization of the protein was performed using SDS-PAGE to determine molecular weight, the Lowery assay to determine protein concentration and a riboflavin-binding assay. The aim of this set of experiments is to develop a new senior level biochemistry lab.

CHED 329

Control of protein translational rates by mTOR in v-ras transformed mouse fibroblasts

Hayley B. Hamilton,, Kerry Bruns.Department of Chemistry and Biochemistry, Southwestern University, Georgetown, Texas 78627-0770, United States

Malignantly transformed cells exhibit an abnormal rate of growth relative to normal cells, requiring a higher rate of protein biosynthesis. To study differences in regulation of protein biosynthesis between normal and transformed cells, KBalb cells (Kirsten sarcoma virus transformed embryonic mouse fibroblasts) and their parental cell line, Balb 3T3 cells, were used as models. Translational regulation requires eukaryotic initiation factors, inhibitory binding proteins of initiation factors, and p70 S6 kinase, all of which are substrates of mTOR. Experimental results suggest that changes in the phosphorylation state of substrates of mTOR1 may have effects on the rate of protein biosynthesis in transformed cells.

CHED 330

Identification of a quinone intermediate in the biogenesis pathway of lysyl tyrosyl quinone

Parveen Hussain,, Karlo M. Lopez.Department of Chemistry, California State University, Bakersfield, Bakersfield, CA 93311, United States

The mechanism for the biogenesis of the lysyl tyrosyl quinone cofactor in lysyl oxidase has not been fully characterized. Two mechanistic pathways have been proposed leading to the formation of this cofactor.

Spectrophotometric and redox cycling studies of the K320R mutant of lysyl oxidase (which prevents LTQ formation) have revealed that a quinone is present in the mutant form of the enzyme. Based on these data, mechanistic pathway 1 is proposed as the biogenesis pathway leading to LTQ.

CHED 331

DNA-binding studies of Pax3-FOXO1 through site-directed mutagenesis

Endia Blunt1,, Madhusoodanan Mottamal1,2, Chantelle Collins1, Kelly Johanson1.  (1) Department of Chemistry, Xavier University of Louisiana, New Orleans, Louisiana 70126, United States  (2) RCMI-Molecular Structure and Modeling Core, Xavier University of Louisiana, New Orleans, Louisiana 70126, United States

Alveolar Rhabdomyosarcoma (ARMS) is a malignant, skeletal muscle tumor that occurs primarily in older children and young adults. ARMS is frequently caused by the transcription factor, Pax3-FOXO1, which retains the full Pax3 DNA-binding domain and a truncated FOXO1 DNA-binding domain. While the Pax3 domain has been thought to direct DNA binding, the ability of the truncated FOXO1 domain has never been directly tested. The overall goal of this project is to characterize the activity of the truncated FOXO1 DNA-binding domain. In the full FOXO1 DNA-binding domain, Arg225 and Ser235 are known to be important for maintaining DNA contacts, and these residues are predicted to be necessary in the truncated system. Here, we present our studies on the affinity of Pax3-FOXO1 for Pax3 and FOXO1 recognition sequences in vitro as well as the effect of Arg225 and Ser235 site-directed mutagenesis on the affinity for these sequences.

CHED 332

Measuring the rates of nitric oxide release from heme proteins

Shelby D Arleth,, Miranda L Gathright,, Truc T T Nguyen,, Stephen E Valacer,, Colin R Andrew.Department of Chemistry & Biochemistry, Eastern Oregon University, La Grande, OR 97850, United States

Reactivity of nitric oxide (NO) with iron-containing centers of heme proteins occurs in a variety of physiological processes, including heme-based NO signaling (e.g. soluble guanylate cyclase) and NO detoxification (e.g. NO reductases). The kinetic stability of heme-nitrosyl complexes is reflected in the rate constant for heme-NO release, koff(NO). Here we report different experimental strategies for measuring koff(NO) for a selection of heme proteins, including cytochrome c′ which exhibits a novel heme-NO binding location on the proximal heme face. The influence of heme Fe coordination number and heme protein environment on the kinetics of heme-NO release is discussed.

CHED 333

Using HS SPME and GC-MS to identify microbial volatile organic compounds in fungal strains isolated from Atriplex canescens

Elizabeth Hernandez-Jaimes,, Mary Kopecki-Fjetland.Department of Chemistry, St. Edward's University, Austin, TX 78704, United States

Fourwing saltbush, Atriplex canescens, is an important food source for herbivores in the desert southwest. It produces plant volatile organic compounds (PVOCs) that could possibly serve as the source of attraction for herbivores. Initial studies revealed a symbiotic relationship between A. canescens and various fungal strains including Alternaria, Cladosporium, Phoma, and Nigrosporium. This research aims to isolate and identify microbial volatile organic compounds (MVOCs) released during the growth of each fungal strain using head space solid phase microextraction (HS SPME) and GC-MS. Alternaria versicolor is being used as a model system. HS SPME exposure times and temperatures are being varied to optimize MVOC isolation. Future studies include comparison of the A. canescens PVOC profile with that of the fungal MVOC profiles in order to determine if herbivores are attracted to the plant or to the fungus.

CHED 334

Cryopreservation of unicellular algae

Allyson McDonald,, Bahinah Callahan, Damaris Delgadillo, Betsy Leverett.Department of Chemistry, University of the Incarnate Word, San Antonio, TX 78248, United States

As a means of establishing optimal cryopreservation conditions for commonly used laboratory species of unicellular algae, the freezing tolerance of some representative species has been investigated. Algae were cultivated under constant growing conditions, and subjected to freezing in the presence of a cryoprotective agent, either dimethylsulfoxide (DMSO) or glycerol. The freezing procedures included either a two-step procedure or a controlled cooling method, and viability analysis of previously frozen algae included growth rate, oxygen production, and chlorophyll analysis.

CHED 335

Loss of sigmoidality in fibrin clot formation in the presence of inhibitors acet-LSPR-amide or acet-ISPR-amide

Jessica S Viscomi,, Brandon T Brown Sr., Toni A Trumbo.Department of Chemistry and Biochemistry, Bloomsburg University of Pennsylvania, Bloomsburg, PA 17815, United States

A fibrinopeptide assay was used to compare the rates of uninhibited clot formation and clot formation containing acet-ISPR-amide or acet-LSPR-amide. For LSPR, clot formation was followed by spectroscopic methods. Not only was clot formation inhibited, sigmoidality was lost in the presence of the inhibitor. For ISPR, the velocity of FpA and FpB release was measured using quench methods and HPLC analysis. Michaelis-Menten plots of for FpA release velocity with respect to fibrinogen concentration showed significant inhibition of clot formation with physiological concentrations of fibrinogen. By contrast, plots for FpB release velocity with respect to fibrinogen concentration showed no inhibition of FpB release. The inhibition of FpA and not FpB release suggests that cooperativity is lost during clot formation with the addition of ISPR.

CHED 336

Determination of Vmax and Km for a membrane protease from the periodontal pathogen, Tannerella forsythia, in solutions between pH 6.0 and 8.0

Amy Rost,, Cole Hartfield,, Joseph Paganoni,, Beth A Harville.Department of Chemistry, Drury University, Springfield, Missouri 65802, United States

Tannerella forsythia is an anaerobic bacterium that is associated with severe periodontal disease. T. forsythia produces a membrane bound protease that cleaves both gelatin and collagen. To better understand the ideal conditions for enzyme activity the protease was purified then incubated with highly fluorescein-labeled gelatin in buffers ranging from pH 6.0 to pH 8.0. Enzymatic cleavage of the highly fluorescein-labeled gelatin resulted in relief of fluorescent quenching which was monitored using a Luminescence Spectrophotometer. Increase in fluorescence due to enzymatic cleavage was used to determine Vmax and Km for the enzyme in the different pH buffering systems.

CHED 337

Effects of resveratrol on ultraviolet light-induced skin cell death

George D. Grady,, Kimberly George.Department of Chemistry, Marietta College, Marietta, Ohio 45750, United States

Antioxidants, such as Resveratrol, are suspected to have anti-cancer and anti-tumor effects. Most cases of skin cancer are caused by overexposure to ultraviolet light irradiation. Results from trypan blue cell viability assays, clonogenic cell proliferation assays, western blots of apoptotic PARP protein cleavage, and FLICA assays for apoptotic caspase cascade activation indicate that resveratrol treatment of both normal human HaCaT skin cells and human cancerous melanoma M624 skin cells causes a dose-dependent increase in cell viability. Results also indicate that resveratrol treatment combined with 50 mJ/cm2 ultraviolet B irradiation causes a resveratrol dose dependent decrease in cell viability of both normal HaCaT skin cells and melanoma M624 skin cells. Results from these studies are indicative of the type of cell death occurring: apoptosis, healthy cell death, or necrosis, unhealthy cell death.

CHED 338

Engineering c-type heme in a cyanobacterial hemoglobin

Lukas Gilevicius2,, Matthew R Preimesberger1, Belinda Wenke1, Juliette T. J. Lecomte1.  (1) Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States  (2) Loyola University New Orleans, New Orleans, Louisiana 70118, United States

Among other cyanobacteria, Synechocystis sp. PCC 6803 produces a globin called cyanoglobin or GlbN. What is unique about GlbN is that it is capable of undergoing a post-translational modification (PTM), which covalently links a vinyl group of the heme to a noncoordinating histidine. A similar PTM can be found in c-type cytochromes where both the 2- and 4-vinyl groups undergo addition by cysteines, anchoring ferrous heme to protein through thioether linkages. In this study, the ability for GlbN to form dual histidine linkages analogous to cytochrome c was investigated as well as the resulting effects on protein properties and heme chemistry. The composite optical and NMR data acquired from this project indicated that we succeeded in engineering double His-heme linkages. Preliminary work indicates that the modified protein is more thermally stable, but there are still other properties left to investigate for future work.

CHED 339

Arabidopsis MMD-like genes and their roles in chromosome biology during male reproduction

Megan M Shroder,, Kuntal De, Christopher A Makaroff.Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States

We previously reported the analysis of the Arabidopsis Male Meiocyte Death1 (MMD1) mutant, which exhibits cytoplasmic shrinkage and chromatin fragmentation, leading to male meiocyte apoptosis. MMD1 is expressed during meiosis and encodes a Plant Homeo Domain (PHD) protein. Arabidopsis contains three other MMD1-like proteins, MS1, which is essential for tapetal cell development and MMDL1 and MMDL2, which are expressed at elevated levels in the endosperm and sperm cells, respectively. Genetic analyses were conducted to determine the roles of MMDL1 and MMDL2. Plants homozygous for single mutations in MMDL1 and MMDL2 appear normal, while homozygous mutations in both genes are lethal. Interestingly, while mmdl1-/-mmdl2+/- plants are viable, but display a seed abortion phenotype, mmdl1+/-mmdl2-/- plants are not able to be isolated. The results of more detailed cellular and molecular analyses including the analysis of pollen, female gametophyte, and embryo development will be presented.

CHED 340

Progress towards synthesis of novel RNA phosphoramidite monomer protecting groups

Seth Jones,, Kenda Syler,, Rachael Kew, Vincent Dunlap.Department of Chemistry, Henderson State University, Arkadelphia, Arkansas 71999, United States

With the explosion of new research in the field of RNA, a significant demand for synthesis of oligoribonucleotides has materialized thus allowing the phosphoramidite method to become a very valuable tool in biochemical research. As a result, the demand for synthesis of phosphoramidite monomers has increased. However, there is a lack of selectivity between the 2'- and 3'-hydroxyl groups in RNA for phosphite addition, resulting in a reduction in efficiency of synthesis. Silyl protecting groups have been developed to improve selectivity for the 2'-hydroxyl; but, in order to obtain the greatest utility, yields of the monomer still need to be improved. In order to improve these yields, we have developed structural analogs of the 5'-hydroxyl protecting group dimethoxytrityl (DMT) which contain linker arms aimed at improving selectivity for 3'-hydroxyl phosphitylation. Synthetic methods for assembly of the protecting groups as well as additional developments are presented.

CHED 341

Molecular substrate interactions of lysine deacetylases

Lavoryette S Cannon2,, Jayla D Jones2, Ashley N Matthew1, Asia N Matthew1, Richard G Painter1, Terry J Watt1.  (1) Department of Chemistry, Xavier University of Louisiana, New Orleans, LA 70125, United States  (2) Department of Biology, Xavier University of Louisiana, New Orleans, LA 70125, United States

Lysine deacetylases (KDACs) play critical roles in cell cycle progression, transcriptional regulation, and developmental events, including cardiovascular development and disease and muscular development. In effort to discover what KDAC residues are critical for the activity and stability of the protein, three KDACs were expressed, purified, and found to be active in assays measuring the deacetylation activity. Site-directed mutagenesis was used to introduce an active site histidine to tyrosine mutation in KDAC4 and KDAC7, and as well as combinations with cysteine to alanine mutations in KDAC4. The histidine to tyrosine mutation in both enzymes was determined to be more active by approximately 1000-fold compared to the wild-type enzymes in a commercial assay, whereas the cysteine to alanine mutations reduced activity and stability. Implications for the role of specific residues are discussed.

CHED 342

Analyzing the antimcrobial properties of bacteriostatic copolymer, vinylbenzyl-thymine and vinylbenzyl triethylammonium chloride via 96-well assay

Maureen Corrielus,, Brittany Caruso, Richard Gurney, Jennifer Roecklein-Canfield.Department of Chemistry & Physics, Simmons College, Boston, MA 02115, United States

We present here our work on developing a long-lasting bacteriostatic copolymer, vinylbenzyl-Thymine and vinylbenzyl triethylammonium Chloride (VBT-VBA), which can be applied to surfaces in hospitals. Bacterial infections acquired during patient stay in the hospital have been a long-standing problem. Recent studies have shown the antibacterial action of substituted VBT-VBA polymers against E.coli. We are examining the effect on growth these polymers have against 6 other pathogenic bacteria commonly acquired in hospitals. We will also be developing new methodology to perform these antibactierial assays at high-throughput using a 96 well plate assay, utilizing the recently purchased ViaFlow robotic liquid handler. The outcome of this work may lead to the development of a commercial product that will dramatically decrease the number of bacterial infections that patients receive from hospitals.

CHED 343

Determination of the binding constant when glycitein is complexed with rat estrogen receptor beta

Chealse M Stokes,, Greg Marks.Department of Chemistry, Carroll University, Waukesha, Wisconsin 53186, United States

Estrogen functions by binding to receptors that control gene transcription, leading to the creation of proteins that regulate several functions within an organism. The hormone/receptor binding event can be blocked by the binding of molecules that are structurally similar to estrogen, causing various developmental issues, specifically causing damage to the ovarian follicles. There is a gap current literature that would offer a solution as to how conformational changes in proteins can be caused by the binding of incorrect ligands, triggering the proteins to function differently. Glycitein, a phytoestrogen found in soy, is used to characterize the effects of phytoestrogens on cell signaling with estrogen receptor beta (ERβ), using rats as a model system. The ligand binding domain (LBD) of rat ERβ was subcloned using PCR. Escherichia coli is ideal for bacterially expressing rERβ LBD. Isothermal calorimtry can be used to determine the binding affinity for estrogen and glycitein.

CHED 344

Photophysical evaluation of 5-aryl pyrimidines

Jake Firmender,, Brandon Litwin, Nicholas J. Greco.Department of Chemistry, Western Connecticut State University, Danbury, CT 06810, United States

Deoxyribonucleic acid (DNA) is an essential biomolecule whose properties have been of scientific significance since its discovery. Experimentation with DNA has focused on modifications made to the sugar, backbone or nucleobases of native nucleosides. Through studying the modified nucleotides a greater understanding of their properties and overall stability can be reached. Our research is focused on a series of 5-aryl nucleosides, whose photophysical properties will be investigated. The absorption and emission properties of these modified nucleosides will be used to determine the location of the modified nucleotides within the DNA duplex.

CHED 345

Effect of 7-hydroxyflavone and fluconazole on the CYP450-2C9 mediated metabolism of ibuprofen

Emily M Lauterbach,, Daryle Fish.Department of Chemistry, Saint Vincent College, Latrobe, PA 15650, United States

The overall goal of this research is to determine the effects of fluconazole and 7-hydroxyflavone on the cytochrome P450-2C9 mediated metabolism of ibuprofen. The fluconazole and 7-hydroxyflavone will both be administered individually to the ibuprofen and cytochrome complex. Ibuprofen is a non-steroidal anti-inflammatory drug that is commonly used for pain reduction and inflammatory diseases. 7-hydroxyflavone is a flavonoid, which is a class of dietary phytochemicals, which is a chemical compound that occurs naturally in plants. 7-hydroxyflavone has a known interaction with the CYP450-2C9 enzyme. Fluconazole is often used to treat fungal infections and meningitis caused by fungus. This drug is also known to have an interaction with the CYP450-2C9. Throughout this research, the final products will be analyzed by the High Performance Liquid Chromatograph. The drugs ibuprofen, fluconazole, and 7-hydroxyflavone will all be metabolized in order to produce the metabolites associated with each of them.

CHED 346

Extraction and identification of Bifidobacterium animalis from commercially available yogurt using polymerase chain reaction

BreAnne DeMarco,, Diana Hoover.Division of Natural and Health Sciences, Seton Hill University, Greensburg, PA 15601, United States

Increasing concerns about food safety has lead to an increase in the importance of methods to identify food components. In yogurt with live cultures, it is possible to find several types of bacteria. One popular commercial brand claims to use a specific strand of Bifidobacterium animalis, which is a strain of Gram positive bacteria. The purpose of this experiment was to extract DNA from the bacteria in this brand of yogurt and attempt to identify it as DN-173010 strain I-2494, a particular strain of Bifidobacterium animalis, subspecies lactis. As a control, DNA extracted from yogurt was compared with human and Micrococcus luteus DNA. The DNA from each sample was extracted using a QuiAmp kit and amplified with PCR using known primers for the specific B. animalis strain. The amplified DNA was separated and visualized using gel electrophoresis. Future work could include comparisons of the bacteria in different brands of yogurt.

CHED 347

Structural and thermodynamic studies of a DNA i-motif

Alexander Buxton,, Mikael McKim, Richard D Sheardy.Department of Chemistry and Biochemistry, Texas Woman's University, Denton, TX 76204, United States

Telomeres are protein DNA complexes found at the ends of eukaryotic chromosomes. The human telomere sequence has a G-rich strand, (TTAGGG), complemented to a C-rich strand, (CCCTAA). Previous studies of the G-rich strand indicate that this sequence folds into a distinct conformation, designated as a G quadruplex, where the GGG bases form G-tetrads while the TTA segments are found in loops joining the tetrads. C-rich DNA has also been shown to form an unusual structure, under slightly acidic conditions, designated as the i-motif. For this aspect of the project, we are investigating the structure and stability of the conformation formed from (CCCTAA)4 in the presence of either Na+ or K+ at pH values ranging from 5.0 to 7.5. We will present circular dichroism (CD) spectroscopic determinations to demonstrate the pH induced formation of the i-motif for this sequence. In addition, we will report results of the effect of a crowding agent (PEG) on the single strand to i-motif equilibrium.

CHED 348

Search for the catalytic subunit of DNA polymerase α in ​Thermomyces lanuginosus

Sonia T. Han,, Chelsea E. Meier,, Ira M. Simet.Department of Chemistry and Biochemistry, University of Northern Iowa, Cedar Falls, Iowa 50614, United States

DNA polymerases are the enzymes responsible for replicating DNA, with DNA polymerase α's (DNAPα) initiating the replication process in eukaryotes. Unfortunately, many DNA polymerases are not very stable, making study of these enzymes difficult. Thermomyces lanuginosus (TL) is a thermophilic fungus, so its DNA polymerases are expected to be heartier and to have a higher temperature tolerance; for this reason, TL has become a target for study. Experiments designed to determine the gene sequence of the catalytic subunit of DNAPα have been undertaken using large scale culture of TL. This sequence appears to be partly conserved among eukaryotes, though little research has been done on fungi apart from Saccharomyces cerevisiae. Using primers based on known sequences from a handful of other fungi, a possible expressed sequence tag (EST) has been identified. This EST will be sequenced and then used to quantitate DNAPα catalytic subunit mRNA in TL.

CHED 349

Analysis of the mutagenic and biophysical characteristics of nanoparticles in common consumer products

Nicholas Eberhart,, Sean Divoky,, Virginia Smith.Department of Chemistry, United States Naval Academy, Annapolis, Maryland 21401, United States

Nanoparticles are used in a wide range of applications throughout the world, including many common consumer products. Metal-oxide nanoparticles such as ZnO and various forms of TiO2 are especially useful. Despite the popularity of nanoparticles, however, relatively little research has been done on the unintended effects nanoparticles might have on the human body. We have used classical microbiological techniques and modern spectroscopic methods to determine the possible mutagenic and biophysical effects of metal oxide nanoparticles on living organisms and membrane bilayers. The Ames Test and bacterial growth assays were used to determine the mutagenicity of several metal-oxide nanoparticles. By incorporating spin-labeled and fluorescently-tagged phospholipids into unilamellar liposomes, we investigated the effects of these same nanoparticles using fluorescence emission and electron paramagnetic resonance spectroscopy. The combined results of these experiments provide information on both the physiological effects and possible mechanisms of action of nanoparticles on living systems.

CHED 350


CHED 351

Expression and identification of GPR133, a human orphan G-protein coupled receptor

Cassandra L. Sidone,, Caleb S. Lougheed, Dale S. DiSalvo, Thomas Frielle.Department of Chemistry, Shippensburg University, Shippensburg, PA 17257, United States

Sixty percent of all human G protein-coupled receptors (GPCRs), including GPR133, do not have an identified agonist, so are termed “orphan receptors.” The primary structure of GPR133 is similar to four previously identified D. discoideum GPCRs whose agonist, extracellular cAMP, initiates chemotaxis and cellular development suggesting that the agonist of GPR133 may also be cAMP. To ensure high expression levels, a mammalian expression vector was constructed that included the sequence encoding the N-terminal 20 amino acids of bovine rhodopsin inserted after the signal peptide sequence of GPR133. After transfection of COS-7 cells, the ability of extracellular cAMP to increase intracellular cAMP in a GPR133-dependent fashion was assessed using a fluorescence resonance energy transfer assay.

CHED 352

Characterizing the antibacterial activity of a VBT/VBA copolymer against common nosocomial gram-negative bacteria: Applications for new surface coating

Cynthia Reynolds,, Brittany Caruso, Richard Gurney, Jennifer Roecklein-Canfield.Department of Chemistry, Simmons College, Boston, MA 02115, United States

Hospital acquired infections have become a growing problem due to the proliferation of bacteria on surfaces and the overuse use antimicrobial products, leading to bacterial resistance. We discuss here a polymer of Vinylbenzyl Thymine (VBT) and Vinylbenzyl Triethyl Ammonium (VBA), which was synthesized and analyzed for antibacterial properties using qualitative and quantitative bacterial assays. Preliminary findings suggest concentrations as low as 1% polymer solution are antibacterial. The VBT/VBA polymer shows promising antibacterial results based on the decrease in the number of colony-forming units of E.coli in the presence of the polymer. We report here the time course of antibacterial activity of the VBT/VBA polymer against 6 nosocomial bacteria strains and new methodology for cross-linking and adherence of the polymer to laminate surfaces.

CHED 353

Cloning, expression, and purification of the pyruvate dehydrogenase complex subunits E1α, E1β, E2, and E3 from the pdhABCD operon of Bacillus subtilis

Laura A Bowman2,, Geoff Briggs1, Kent Molter2, Panos Soultanas1.  (1) Centre for Biomolecular Sciences, University of Nottingham, Nottingham, Nottinghamshire NG7 2RD, United Kingdom  (2) Department of Chemistry, Carroll University, Waukesha, WI 53186, United States

Pyruvate dehydrogenase (PDH) is a four-enzyme complex which is employed in the lower half of glycolysis and is also suspected of regulating lagging strand synthesis of DNA. It is unknown which of the PDH subunits interact with subunits of DNA helicase to regulate synthesis. Environmental factors were previously assumed to regulate DNA replication, but there may instead be a complex regulatory system that directly links enzymes in glycolysis and DNA replication. In this research the four subunits of the PDH enzyme (E1a, E1b, E2, and E3) were obtained by cloning the PDH gene from Bacillus subtilis, expressing the protein, and purifying via fast protein liquid chromatography. Interactions between PDH subunits and enzymes in DNA helicase responsible for lagging strand synthesis were tested using analytical gel filtration. Improved methods of purifying the PDH subunits using readily available materials were also explored.

CHED 354

Deciphering the breast cancer histone code

Lisa M. Orr1,, Linley Moreland2, Nathan Avaritt2, Alan J. Tackett2.  (1) Department of Chemistry, University of Arkansas at Little Rock, Little Rock, Arkansas 72204, United States  (2) Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, United States

Chromatin, a complex of DNA wrapped around a core of histone proteins, greatly reduces the size of DNA. Processes like replication and transcription are dependent upon chromatin density because tightly packaged DNA cannot be accessed by proteins involved in these activities. Histone post-translational modifications (PTMs) can alter chromatin density enabling or inhibiting replication and transcription. Alterations in levels of transcriptional activating and inactivating PTMs have been associated with progression of numerous cancers. A recent study has shown that expression of estrogen receptor in breast cancer is regulated by epigenetic aberrations. Described here is a mass spectrometric approach for correlating PTM status with hormone responsiveness in two breast cancer cell lines. It is hypothesized that differences in histone modifications exist between cancer cell lines derived from ER+ and ER- breast tumors. Identification of differences in PTMs between the tumor types may provide insights into new treatments that target histone-modifying enzymes.

CHED 355

Solvent-dependent structure of the endogenous opioid peptide β-neoendorphin

Jasmine Hill,, Khushikumari Patel, Brittany Morgan, Nsoki Phambu.Department of chemistry, Tennessee State University, Nashville, Tennessee 37209, United States

Structural changes for the endogenous opioid peptide β-neoendorphin (β-NE) in various solvents were investigated using infrared, NMR, ThT-fluorescence and Dynamic light scattering (DLS) techniques. The peptide structure was studied in aqueous solution, sodium dodecylsulfate (SDS), trifluoroethanol (TFE), and in the presence of the anionic model membrane dipalmitoylglycerophosphoglycerol (DPPG). FTIR with second derivative resolution and curve-fitting methods indicates that β-NE adopts a major β-sheet structure in water and SDS micelles. A substantial reduction of the β-sheet structure is observed in TFE, with an increase in a-helix structure. DLS experiments reveal that β-NE increases the size of DPPG aggregates. ThT-fluorescence results indicate that β-NE adopts a beta-sheet structure while interacting with DPPG in water, in agreement with the FTIR results. The interaction of β-NE with DPPG in TFE are also discussed. Proton NMR spectra shows that the N atom of the amide group of β-NE is involved in the interaction with DPPG.

CHED 356

Quantification of CDP-choline in tissues and body fluids using LC/SRM/MS and stable isotope dilution

Ashley Freeze1,, Joshua Cummings1,, Shucha Zhang2, Walter B Friday2.  (1) Department of Chemistry, Catawba College, Salisbury, NC 28144, United States  (2) Department of Metabolomics, University of North Carolina at Chapel Hill, Nutrition Research Institute, Kannapolis, NC 28081, United States

CDP-choline, also known as cytidine 5'-diphosphocholine or citicoline, is the active form of choline that is important for normal membrane function, acetylcholine synthesis, lipid transport, and methyl metabolism. CDP-choline supplements are available in the market to promote brain function. Once absorbed, CDP-choline is widely distributed throughout the body, crosses the blood-brain barrier and reaches the central nervous system, where it is incorporated into the membrane and microsomal phospholipid fraction. Despite its importance, only a limited number of assays are available in literature and have not been extensively applied to biological samples due to undesirable sensitivity and selectivity. In this study, a new liquid chromatography-selective reaction monitoring-mass spectrometry (LC/SRM/MS)-based assay is described for quantification of CDP-choline. The assay is evaluated by parameters such as precision, accuracy, linear dynamic range, limit of detection and limit of quantification. The concentrations of CDP-choline in various samples such as tissues, plasma and urine are determined.

CHED 357

Influence of a coiled-coil isoleucine zipper on the trimerization and endosomolytic activity of the E5-TAT-mCherry protein

Valerie Nickel1,, Ting-Yi Wang2, Jean-Philippe Pellois2.  (1) Department of Chemistry, Ouachita Baptist University, Arkadelphia, AR 71998, United States  (2) Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, United States

The E5-TAT-mCherry protein is designed to initiate cellular uptake through endocytosis and react to the acidification of the endosomes by causing membrane lysis and cytosolic delivery. The cell penetrating peptide TAT from the HIV transcription activator binds to the cellular membrane and triggers endocytosis. E5 is a derivative of the fusogenic peptide HA2 from the influenza hemagglutinin protein and reacts to the acidification of the endosomal lumen by inserting into the membrane and increasing permeability. Cytosolic delivery has been achieved using E5-TAT-mCherry, although efficiency still remains low. A pH-sensitive isoleucine zipper (IZdep) has been incorporated into the protein in order to increase its endosomolytic activity. Under acidic conditions IZdep forms a triple stranded coiled coil but remains as a monomer under neutral conditions. Preliminary results suggest that IZdep is creating a mixture of oligomerization states and that TAT is interacting with charged residues on IZdep, decreasing membrane binding efficiency.

CHED 358

Purification of α-Amylase from human saliva from diverse populations

Paul Cornelius,, Diana Hoover.Division of Natural and Health Sciences, Seton Hill University, Greensburg, PA 15601, United States

The scientific community has examined the effects smoking has on males and females at length. But what effects does smoking and gender have on the digestion of starch in the mouth? The purpose of this study was to determine if a relationship existed between smoking habits and gender, in terms of the activity of α-amylase. α-Amylase, an enzyme located in human saliva that functions in the digestion of starch, was isolated from several human saliva samples and analyzed using starch and iodine reagent. Twenty samples were collected from participants aged 18-24 years, who had not consumed food in the past hour. The results will be useful in determining if enzymatic activity of α-amylase is hindered based on smoking habits or gender, providing a foundation for future experimentation into how these variables affect DNA coding for this enzyme.

CHED 359

Characterization of cationic DNA transfection agents binding to supramolecular G-DNA

Zachariah Henseler,, Thomas Marsh, Lisa Prevette.Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105, United States

Guanine-rich nucleic acids self-assemble into a polymorphic family of quadruple helical structures known as G-DNA. Its common structural motif is a coplanar tetrad of guanine bases that, when stacked, have the capacity to coordinate some cations. Sequences capable of adopting a G-DNA structure are found throughout the genomes and their biological functions are linked to genome stability, regulation of gene expression and cellular senescence. This work describes interactions of cationic polymers used as DNA transfection agents with a supramolecular G-DNA known as a G-wire. Polyethyleneimine (PEI), TAT peptide and PAMAM dendrimer show high affinity for G-wires self-assembled in the presence of Na+, K+ and NH4+ when measured by Isothermal Titration Calorimetry (ITC). Dynamic light scattering (DLS) revealed the emergence of polydisperse aggregates form at charge ratios greater than 1(+:-) ranging in diameter (100-1000 nm). The analyses of binding interactions indicate that G-DNA remains intact, supporting results from ITC and DLS.

CHED 360

Cyclocreatine:membrane interactions studied by differential scanning calorimetry and fluorescence emission spectroscopy

Joshua Sohn,, Allison Maher,, Virginia F Smith.Chemistry, United States Naval Academy, Annapolis, MD 21412, United States

Cyclocreatine (CCr) and its phosphorylated derivative, PCCr, have been shown to have medically important properties in the heart and nervous system, but their interactions with cell membranes are not well understood. We used liposomes formed from cardiac and brain tissue lipid extracts to model the cell membranes in order to study the membrane interactions with CCr and PCCr. We used differential scanning calorimetry to obtain Tm values and changes in enthalpy associated with the addition of the creatine analogs. Using phospholipids with either DANSYL-labeled headgroups or NBD-labeled acyl chains we were able to monitor CCr and PCCr interactions with the membrane bilayer. By varying the temperature we were able to evaluate the effect on membrane thermal stability. By using polar and total lipid extracts we were able to evaluate how creatine analogs interact with membrane components of different polarity. The combined results provide a fuller picture of creatine-membrane interactions.

CHED 361

Isolation and determination of the DNA gene sequence of actin for the slime mold Stemonitis flavogenita

Brett A. Williams,, Jeannie T. B. Collins.Department of Chemistry, University of Southern Indiana, Evansville, IN 47712, United States

The slime mold Stemonitis flavogenita was studied to determine the gene sequence for actin. Actin, a cytoskeletal protein, is highly conserved among eukaryotes; however, the actin sequence for this species is unknown. DNA and RNA were isolated from the aphanoplasmodial and coralloid stages of this organism. Known actin gene sequences were aligned and compared in order to determine the best primer sequences for PCR. After preparing cDNA samples from the RNA isolations through reverse transcription, the DNA and cDNA samples were amplified using PCR under various conditions. The amplified samples were analyzed using agarose gel electrophoresis. It was determined that samples that were amplified at temperatures near 37°C produced the largest bands, although they were not the strongest bands. The target DNA size is 1130 bases, and a couple of samples are larger than this. Additional isolations will be performed and analyzed and the results will be presented.

CHED 362

Synthesis of naphthyridine/azaquinoline analogs for the disruption of TNR expansions in the base excision repair mechanism

Jay D. Pike, Nicole Sassu,, Luke Sejkora,, Eileen Colliton, of Chemistry & Biochemistry, Providence College, Providence, RI 02918, United States

Several neurological disorders result from the expansion of (CAG)n/(CTG)n trinucleotide repeat (TNR) microsatellite sequences in the human genome. As part of the expansion process, the formation of non-B DNA hairpin conformations has been proposed in the base excision repair mechanism, within which an oxidized guanine residue is excised by 7,8-dihydro-8-oxoguanine glycosylase and repaired by β-polymerase. At this stage, DNA slippage can occur, forming hairpin conformations and leading to the addition of extra bases in the sequence. We propose that developing small molecules that have high binding affinity to the CAG/CTG sequence can be used to “clamp” the DNA duplex, preventing such slippage. We have constructed a model DNA system with a (CAG)20/(CTG)20 unit in a 100-mer duplex, with an abasic site at the first 5'-CAG repeat site. This work focuses on the design and synthesis of naphthyridine/azaquinoline analogs and their potential to inhibit TNR expansion during the repair process.

CHED 363

Resveratrol and resveratrol derivatives as class IA PI3K inhibitors

Cassandra N Petty,, Eamonn F Healy, Peter King.Department of Biochemistry, St. Edwards University, Austin, TX 78704, United States

Atherosclerosis is an accumulation of fatty deposits that can form plaque and block the flow of blood. The hallmark of early atheroma is the appearance of foamy macrophages which secrete cytokines, chemokine's, and reactive oxygen species. Resveratrol is found in the skin of grapes and is an effective inhibitor of the COX reaction scheme, known activator of the inflammatory response. We measured the effects of resveratrol on phagocytosis, reactive oxygen species production, foamy cell formation, and cytokine production, and found that resveratrol effectively inhibited production on all accounts. This work also verifies α-PI3Kinase as a key target for inhibition by resveratrol. Using Accelrys Discovery Studio and a crystal structure of α-PI3K obtained from PDB we are able to demonstrate that reveratrol and certain resveratrol derivatives exhibit high binding affinities to PI3-Kinase. We found cyclopropyl-diacetyl resveratrol to have the highest binding efficiency due to its orientation in the binding pocket.

CHED 364

Effect of spent media isolated from Lactobacillus plantarum WCFS1 on biofilm formation by Staphylococcus aureus

Taylor B. Stanford1,, Huanli Liu2, Mark E. Hart2.  (1) Department of Chemistry, Ouachita Baptist University, Arkadelphia, AR 71998, United States  (2) U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR 72079, United States

Staphylococcus aureus is a gram-positive, facultative anaerobic bacterium that causes the life threatening disease called Toxic Shock Syndrome (TSS), which became prevalent in the late 70s in menstruating women using highly absorbent tampons (2). The incident of TSS was reduced significantly when the product was removed from the market; however, recent surveys indicate that TSS is on the rise again (1). Lactobacillus species are a predominant member of the vaginal microflora and are known to afford a level of protection to invading bacterial pathogens. An in vitro biofilm microtiter plate assay was used to examine the effect of L. plantarum WCFS1 spent media on biofilm formation by a toxic shock syndrome toxin-1 producing strain of S. aureus in various types of media under different pH conditions. We concluded biofilm formation increased in a modified genital tract secretion media, which mimics the vaginal environment, under neutral pH conditions.

CHED 365


CHED 366

Determination of sodium fluoride and sodium monofluorophosphate in samples using quantitative 19F-NMR

Alysha Alaimo,, Diana Hoover.Division of Natural and Health Sciences, Seton Hill University, Greensburg, PA 15601, United States

Teeth are protected by a hard enamel layer. By using fluorine-containing toothpaste the possibility of tooth decay will decrease, however, overdose of fluorine may induce dental fluorosis, which is a defect in tooth enamel caused by excessive fluoride intake. Studies show that many children ingest more fluoride from toothpaste than is recommended as a total daily intake, which poses several health concerns. Therefore, quantitative determination of fluorine in toothpaste is necessary for health purposes. For this study, 19F-NMR was used to determine the concentration of fluorodizers (sodium fluoride and sodium monofluorophosphate) in toothpaste, but this technique can also be useful for determining the amount of fluoride in other compounds such as drinking water. With the 19F-NMR spectra the fluoride content and the speciation information of the fluoride in each compound can be determined.

CHED 367

Retinoids modulate cellular adhesion and proliferation in the human K562 cell line

Amanda M Hanson,, Jenni Goodwin, Melissa D Kelley.Department of Chemistry, University of Central Arkansas, Conway, AR 72035, United States

Retinoids are essential for such critical life processes as cellular adhesion and proliferation. All-trans-retinoic acid (t-RA) and 9-cis-retinoic acid (9-cis-RA) serve as ligands for retinoic acid and retinoid X receptors and can form heterodimeric partners with peroxisome proliferators-activated receptor gamma (PPARgamma). Proliferation and cellular adhesion assays were performed with K562 cells treated with troglitazone, t-RA, 9-cis-RA or troglitazone and t-RA or 9-cis-RA. Cellular adhesion assays were conducted on three substrates: fibronectin, FN-120, or FN-40. Our data suggest that, in the presence of troglitazone, cells treated with t-RA or 9-cis-RA increase cellular adhesion to both fibronectin and FN-120. Additionally, K562 cells treated with t-RA or 9-cis-RA and troglitazone decrease cellular proliferation compared to cells treated with t-RA or 9-cis-RA alone. We examined t-RA and 9-cis-RA metabolism in the presence or absence of troglitazone using liquid-liquid extraction and reverse-phase HPLC. Troglitazone appears to increase retinoid availability and modulates cellular proliferation and adhesion.

CHED 368

Investigating the role of non-coding RNAs in pericentric heterochromatin formation

Justin M Smith1,2,, Whitney L Johnson1, William T Yewdell1, Aaron F Straight1.  (1) Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305, United States  (2) Department of Chemistry, Catawba College, Salisbury, NC 28144, United States

Proper chromosome segregation is necessary during mitosis and meiosis in order to accurately segregate a cell's genome. One domain important to this process is the pericentric heterochromatin which surrounds the core centromere on chromosomes and ensures equal segregation of the genome. Previous research has shown that centromeric RNA plays a role in the formation of the pericentric heterochromatin in Schizosaccharomyces pombe. However, it is not clear if recruitment of pericentric proteins is dependent on centromeric RNA in human cells. To test the effect of disrupting centromeric RNA in vivo, we generated fusion protein constructs consisting of a pericentric localizing protein, green fluorescence protein (GFP) and RNase. We analyzed the expression of fusion proteins by Western blot, and confirmed their RNase activity. Finally, we tested the effect of expressing these fusion proteins in cells by analyzing fixed cells via immunofluorescence microscopy.

CHED 369


CHED 370

Generating new protein models for thiolate-ligated heme ligand switch proteins using cytochrome c

Lindsey M. Ludwig,, Melisa M. Cherney.Department of Chemistry and Biochemistry, University of Northern Iowa, Cedar Falls, IA 50614, United States

Thiolate-ligated heme proteins contain a heme cofactor that is bound to a cysteine residue. Included in this group are six-coordinate heme proteins which are regulated by a ligand switch from the cysteine thiolate ligand to a neutral ligand upon reduction of the heme iron. The exact mechanism of this switch is unknown. The purpose of this research is to create a model protein using cytochrome c, a robust and incredibly well-characterized protein which contains a built-in ligand switch (the alkaline conformational transition). In this study we have generated a series of yeast iso-1-cytochrome c variants which contain a Met80 to Cys mutation that creates a thiolate-ligated ferric heme. These variants contain mutations which introduce potential histidine ligands for the switch, eliminate native histidine residues, and/or stabilize the overall protein structure. The results of these studies and their relevance to other heme-thiolate proteins will be discussed.

CHED 371

Quantification of blood plasma ghrelin levels in aggressive and depressive CF-1 male mice Mus musculus

Clint Badger1,, Boyce Jubilan2, Julie Aaron1.  (1) Department of Natural Science, DeSales University, Center Valley, PA 18034, United States  (2) Department of Social Sciences, DeSales University, Center Valley, PA 18034, United States

Ghrelin is a peptide hormone secreted by the stomach in mammals. Ghrelin has been linked to increase the food intake of high fat foods while also being a potential stimulator of growth hormone from the anterior pituitary gland. Elevated levels of ghrelin have been identified in depressed humans, however quantitative studies of ghrelin levels in the blood stream in highly depressed and aggressive mammals have not been completed. In this study ghrelin levels are monitored in CF-1 laboratory mice, Mus musculus, prior to and after socialization by a chronic social defeat stress protocol, resulting in aggressive and depressive groups. It is hypothesized that aggressive mice will have lower ghrelin concentrations and depressive mice will have higher ghrelin concentrations. Blood plasma ghrelin levels are analyzed using a mouse ghrelin specific ELISA assay from EMD Millipore.

CHED 372

Properties of a new series of acetyl-ethyl-pyrazine thiosemicarbazones (ACEP-TSC's) and their copper(II) complexes

Alexandra Arriaga,, Carrie Thompson, Kathleen Mansur, Edward C Lisic.Department of Chemistry, Tennessee Technological University, Cookeville, TN 38505, United States

Thiosemicarbazone compounds are a class of multidentate ligands that contain potential binding sites for a wide variety of metal ions such as iron and copper. This work will present the synthesis of a series of new, never before synthesized, 2-acetyl-3-ethylpyrazine thiosemicarbazone compounds (AEPZ-TSC's). These new compounds are potential anti-cancer agents, as they most likely interfere with ribonucleotide reductase, an iron-containing enzyme used by cells to produce DNA. They are structurally similar to Triapine, which has undergone Phase 2 clinical trials. The work includes the structural characterization of the new compounds by 1H NMR spectroscopy. The purpose of this project was to synthesize, characterize, and determine the minimum inhibitory concentration (MIC) of this series of compounds for four bacteria (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa), two yeast (Candida albicans and Saccharomyces cerevisiae), and a mold (Aspergillus niger) to determine the indication of biological activity and anti-proliferation capacity.

CHED 373

Pyruvaldehyde bis-thiosemicarbazone ligands and metal complexes

Amanda Koch,, Christine N Beck, Kathleen Mansur, Edward C Lisic.Department of Chemistry, Tennessee Technological University, Cookeville, TN 38505, United States

Pyruvaldehyde was reacted with seven different thiosemicarbazide compounds to give a series of seven pyruvaldehyde bis-thiosemicarbazone compounds. These complicated compounds were characterized by 1H NMR. The compounds produced are: pyruvaldehyde bis-thiosemicarbazone, pyruvaldehyde bis-methylthiosemicarbazone, pyruvaldehyde bis-ethylthiosemicarbazone, pyruvaldehyde bis-tertbutylthiosemicarbazone, pyruvaldehyde bis-benzilthiosemicarbazone, pyruvaldehyde bis-phenylthiosemicarbazone, and pyruvaldehyde bis-dimethylthiosemicarbazone. These compounds were reacted with various metals to form metal complexes and then tested to prove or disprove biological benefits. The antimicrobial activity of these synthesized pyruvaldehyde thiosemicarbazones and the metal complexes of these compounds will be tested by determining the minimum inhibitory concentrations against four bacteria (Bacillus subtilis, Saphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa), two yeast (Canida albicans and Sacchromyces cervisiae), and two molds (Aspergillus niger).

CHED 374

Synthesis and characterization of new copper (II)quinoline-2-carboxaldehyde thiosemicarbazone compounds

Lizzie L Monroe,, Carrie Thompson, Kathleen Mansur, Edward C Lisic.Department of Chemistry, Tennessee Technological University, Cookeville, TN 38505, United States

This research involved the synthesis of new quinoline-2-carboxaldehyde thiosemicarbazone compounds (QCA-TSC), characterized through 1H NMR, for the purpose of forming complexes with transition metals. Those compounds were reacted with Cu(II). We present here the synthesis of new Cu(II) quinoline-2-carboxaldehyde thiosemicarbazone (Cu-QCA-TSC)compounds. Various entries on thiosemicarbazones in the literature indicate a potential use in biological and biomedical applications.

CHED 375

Investigations of PurP proteins from Methanocaldococcus jannaschii and Thermococcus kodakarensis

Noah R. Aguayo,, Catherine A. Sarisky.Department of Chemistry, Roanoke College, Salem, Virginia 24153, United States

Our lab studies purine biosynthetic pathways in Archaea. PurP enzymes catalyze the ATP- and formate-dependent conversion of 5-aminoimadazole-4-carboxamide-1-β-D-ribofuranosyl 5'-monophosphate (ZMP) to 5-formaminoimidazole-4-carboxamide-1-β-D-ribofuranosyl 5'-monophosphate (FAICAR). The genes from the organisms Methanocaldococcus jannaschii (MJ0136) and Thermococcus kodakarensis (TK0196 and TK0203) were cloned into pMAL-c5E vector. Previously we have investigated in vitro activity of these predicted PurP enzymes. Neither Thermococcus kodakarensis protein showed activity in vitro. As an alternate approach, we are testing a complementation system using purine auxotrophic E. coli cells. It was found that the cells with the MJ0136-containing vector exhibit prototrophy. Complementation results for TK0196 and TK0203 will be discussed.

CHED 376

Identification of alternative pathways to prenyl diphosphates involved in cell wall assembly in Mycobacterium tuberculosis

Courtney Nygaard,, Francis M Mann.Department of Chemistry, Winona State University, Winona, Minnesota 55987, United States

Mycobacterium tuberculosis (Mtb) has six genes, Rv0562, Rv0989c, Rv1086, Rv2361c, Rv3383c, Rv3398, that encode for related enzymes. These enzymes produce various prenyl diphosphates (PDP), which are different sizes and stereochemistry. The products of these enzymes facilitate the production of cell wall components and PDPs assist in the transfer of polysaccharides into the cell wall. The proteins encoded by Rv0989c, Rv1086, and Rv2361c, make products that elongate to form decaprenyl phosphate, which is the natural pathway and product in Mtb; however, there are alternative pathways indicating that Mtb can survive by assembling its cell wall with different products. This experiment identifies alternative natural pathways, which could identify enzymatic antibiotic targets. Escherichia coli is utilized to express the Mtb genes in non-native sequences and assess the production of novel PDPs. The products were harvested from lysed cells and analyzed via GC-MS and TLC against a background E. coli metabolism.

CHED 377

Effect of tris buffer on calf intestinal alkaline phosphatase

Ajibola B Bakare,, Eva Csuhai, Kayarash Karimian, University, Lexington, Kentucky 40508, United States

Enzymes are highly selective biological molecules that speed up the rate of metabolic reaction. Living organisms usually maintain a relatively constant internal environment that keeps enzymes active, and deviation from norm would denature enzymes. This is true for most enzymes; however, calf intestinal alkaline phosphatase deviates from this norm. Our previous experiment showed that calf intestinal alkaline phosphatase was activated by trifloroethanol in carbonate buffer at pH 10 and temperatures 45°C, 65 °C. In our study, we tested the effect of Tris buffer at pH of 8 and 9, and at temperatures 25 °C, 45 °C and 65 °C on calf intestinal alkaline phosphatase. Para-Nitophenylphosphate was used as a substrate for the alkaline phosphatase in this experiment, after which the absorption and concentration of the reaction were recorded using spectrophotometer.

CHED 378

Gallic acid, an inducer of apoptosis to human oral carcinoma HSC-2 cells, as mediated through oxidative stress

Esther F. Robin,, Jordana R. Wietschner,, Jeffrey H. Weisburg, Harriet L. Zuckerbraun, Alyssa G. Schuck, Harvey Babich.Department of Biology, Stern College for Women, New York, NY 10016, United States

Gallic acid is preferentially cytotoxic to cancer cells, and acts as a prooxidant to induce cell death via apoptosis. This research demonstrates a cause-and-effect relationship between production of hydrogen peroxide by gallic acid and its subsequent induction of apoptosis to human oral carcinoma HSC-2 cells. FOX assay shows that gallic acid is a strong generator of H2O2. Depletion of intracellular reduced glutathione (GSH,) was observed in HSC-2 cells exposed to increasing levels of gallic acid. Also, the decrease in intracellular GSH in HSC-2 cells treated with gallic acid was reduced by coexposure with CoCl2. Flow cytometric analyses of HSC-2 cells showed that with increased gallic acid concentration, viable cells decreased while apoptotic and dead cells increased. In the presence of Co2+, the cells were essentially rescued from apoptotic death. The mechanism of apoptotic cell death in HSC-2 cells exposed to gallic acid is via the induction of oxidative stress.

CHED 379

Functional dissection of BRCA1 A complex proteins, Abraxas, and BRCC36

Génesis Millán-Serrano1,, Andrew Castillo2, Paul Atanu2, Bin Wang2.  (1) Department of Natural Science, University of Puerto Rico - Aguadilla, Aguadilla, PR 00604-6150, Puerto Rico  (2) Department of Genetics, University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States

Genome integrity is essential for the survival of the cells; therefore the ability to respond to DNA damage is critical. Breast cancer-1 (BRCA1) participates in the DNA damage response and co-localizes with Abraxas and BRCC36, as it forms a multi-protein BRCA1 A-complex. The mechanism by which BRCA1 A-complex proteins functions remains elusive. Abraxas serves as an adapter protein in the complex. BRCC36 contains deubiquitination activity and has recently been observed to multimerize with itself. To further understand the role of BRCA1 A-complex proteins, we aim to dissect these genes functions through the generation of multiple mutants and their expression in cells for functional analysis. Abraxas cDNA mutants were able to detect transient expression in mouse embryonic fibroblasts cells. Dissected BRCC36 clones show that the multimerization domain is located between the MPN domain and Coiled-Coil domain. Further analysis will be performed to comprehend the organization and function of the complex.

CHED 380

NMR study of the thermal denaturation of TIAM PDZ domains

Reena Dev,, David C. Speckhard.Department of Molecular and Life Sciences, Loras College, Dubuque, IA - Iowa 52001, United States

T- cell lymphoma invasion and metastasis 1 and 2 (TIAM1 and TIAM2) proteins are guanine nucleotide exchange factors that specifically activate GTPase Rac and are implicated in the regulation of biological functions. TIAM1 and TIAM2 are composed of different interacting PDZ domains and thus in QM (quadruple mutant) TIAM1, the four residues crucial for the differences in binding specificity for partner peptides were replaced with the corresponding TIAM2 residues and the specificity became more like TIAM2 PDZ domain. Additionally, TIAM1 and TIAM2 domains also display differences in stabilities. TIAM1 can be stored for long period of time while QM and TIAM2 cannot. We have been able to demonstrate differential stabilities of N15 HSQC amide signals in spectra of QM PDZ taken at 25 °C and 45 °C We will report the thermal titration of these groups in the presence/absence of binding partner, and will report how altering the key residues impacts stability.

CHED 381

CYP2E1 overexpression induces mitochondrial biogenesis in HepG2 cells

Logan Rice,, Andres Caro.Department of Chemistry, Hendrix College, Conway, Arkansas 72032, United States

HepG2 cells overexpressing cytochrome P450 2E1 (CYP2E1) were generated by transfection with a pCI expression vector containing the human CYP2E1 cDNA, and selected with the use of geneticin. Overexpression of CYP2E1 was confirmed at the RNA level by reverse-transcriptase PCR, at the protein level by western blot, and at the enzymatic activity level by 7-methoxy-4-trifluorocoumarin O-demethylation. Control HepG2 cells were transfected with the empty pCI plasmid. The content of mitochondrial DNA in CYP2E1-overexpressing HepG2 cells (determined by real-time PCR and expressed relative to nuclear DNA content), was two-fold higher than that of control HepG2 cells. In parallel, the level of reactive oxygen species expressed as dichlorodihydrofluorescein oxidation rate and determined by flow cytometry increased two-fold with respect to control HepG2 cells. These results support a working hypothesis where CYP2E1 overexpression induces mitochondrial DNA synthesis, probably by increasing oxidative stress levels.

CHED 382

Effect of ethanol on mitochondrial DNA in HepG2 cells

Spencer Sanson,, Andres Caro.Department of Chemistry, Hendrix College, Conway, Arkansas 72032, United States

Ethanol metabolism in hepatocytes induces oxidative stress; in turn, oxidants can damage and deplete mitochondrial DNA. The effect of ethanol on mitochondrial DNA (mtDNA) content and oxidative stress of hepatocytes was explored using a human hepatoma cell line (HepG2 cells). Ethanol did not induce significant cell death in HepG2 cells at concentrations of up to 100 mM. Ethanol produced a dose-dependent increase in the level of cellular oxidants, evaluated by dichlorodihydrofluorescein oxidation and determined by flow cytometry. The content of mDNA was determined by real-time PCR and expressed relative to the nuclear DNA content. At 100 mM, ethanol produced a 30% decrease in mtDNA content with respect to untreated cells. These results support a working hypothesis where ethanol produces partial depletion of mtDNA, probably by increasing oxidative stress levels.

CHED 383

Docosahexaenoic acid induces mitochondrial biogenesis in HepG2 cells

Johnny Tran,, Andres Caro.Department of Chemistry, Hendrix College, Conway, Arkansas 72032, United States

Docosahexaenoic acid (DHA) is a polyunsaturated fatty acid abundant in fish oil, which is very sensitive to oxidation; in turn, lipid-derived oxidants can damage and deplete mitochondrial DNA. Mitochondrial biogenesis is a compensatory mechanism which is activated by many cells under oxidative stress to maintain mitochondrial DNA (mtDNA) levels. The effects of DHA on mitochondrial biogenesis in hepatocytes were explored using a human hepatoma cell line (HepG2 cells). At 20 uM, DHA produced a two-fold increase in mtDNA content with respect to untreated cells. Mitochondrial transcription factor A (TFAM) is a key component of the mtDNA biosynthesis pathway. DHA at 20 uM produced a 60% increase in TFAM mRNA, and a 40% increase in TFAM protein levels. Pre-incubation with trolox, an amphipathic antioxidant, prevented the increase in mtDNA caused by DHA. These results support a working hypothesis where DHA increases mtDNA biosynthesis by inducing TFAM expression, probably via oxidative stress.

CHED 384

Use of bioinformatics tools to investigate molybdate ABC transporters in Thiomicrospira crunogena

Emily Santellan,, Teresita Munguia.Department of Mathematics and Science, Our Lady of the Lake University, San Antonio, Texas 78207, United States

Thiomicrospira crunogena is a chemolithoautotroph that lives in deep sea vents in the Atlantic and Pacific oceans. T. crunogena uses reduced sulfur compounds as a fuel source for carbon fixation and has developed multiple adaptations to obtain inorganic molecules to sustain life in deep sea vents. Transporters play important roles in the uptake and export of substrates across the cellular membrane to maintain homeostasis within the organism. The use of bioinformatics tools was used to annotate the molybdate ABC transporter system. Bioinformatic tools help to determine putative structure and location of mod A, mod B, mod C genes on the cellular membrane. Molybdate ABC transporters in T. crunogena do not contain a fourth protein that helps in the transportation of substrates through the cell membrane. Understanding the structure of ATP-Binding Cassette Transporters is important to understanding the movement of substrates and how the substrate is distributed within the cell.

CHED 385

Docosahexaenoic acid induces glutathione synthesis in HepG2 cells

Etienne Nzabarushimana,, Andres Caro.Department of Chemistry, Hendrix College, Conway, Arkansas 72032, United States

Docosahexaenoic acid (DHA) is a polyunsaturated fatty acid abundant in fish oil, which is very sensitive to oxidation; in turn, lipid-derived oxidants can activate redox-sensitive transcription factors to produce a compensatory induction of antioxidant enzymes. The effects of DHA on antioxidant defenses of hepatocytes were explored using a human hepatoma cell line (HepG2 cells). At 20 uM, DHA produced a 3-fold increase in the content of glutathione, the most abundant water-soluble antioxidant, with respect to untreated cells. DHA produced a 60% increase in the mRNA levels of gamma-glutamylcysteine synthetase (GCS), whose protein product catalyzes the rate-limiting step of glutathione biosynthesis. Knockdown of Nrf-2 (a key redox-sensitive transcription factor, which binds to the gamma-GCS promoter) with siRNAs, blocked the effect of DHA on glutathione content. These results support a working hypothesis where DHA increases glutathione synthesis by inducing gamma-GCS expression, probably via Nrf-2.

CHED 386

FT flowering gene examination in Cannabis sativa

Sarah A Anderson1,2,, George Weiblen2, David Speckhard1.  (1) Department of Biochemistry, Loras College, Dubuque, Iowa 52001, United States  (2) Department of Plant Biology, University of Minnesota, Saint Paul, Minnesota 55108, United States

Often plants are used either for their flowers or the fruit that is produced from the flowers; however, the plant must receive triggers for flowering to occur. Many of the exact triggers that cause specific plants to switch from their vegetative states into flowering states have not yet been discovered. The flowering of Cannabis sativa was examined through the isolation of its FT gene. FT has previously shown to be significant in the conversion from vegetative to flowering in model plants. The FT gene in Cannabis was identified, sequenced, and compared to published FT sequences of various other plants to form a phylogenic tree. In Cannabis specifically, active ingredients are found in the flowers; to be able to control when the plant flowers gives control over the production of the active ingredients. Since flowering in Cannabis has not previously been explored, this study was a starting point for future research.

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CHED 388

Evaluation of the azinomycin gene cluster

Chardai Grays2,, Dinesh Simkhada1, Coran M. H. Watanabe1.  (1) Department of Chemistry, Texas A&M University, College Station, Texas 77840, United States  (2) Department of Chemistry, Dillard University, New Orleans, LA 70122, United States

Azinomycins have putative resistance proteins, HRP1 and HRP2, found in the azinomycin biosynthetic gene cluster. These proteins appear to be selective toward azinomycin B (AzB) and demonstrate a protective effect against azinomycin's cytotoxic effect. Understanding the resistance mechanism will aid in the development of AzB as a potent chemotherapeutic agent. AziA2 is also found within azinomycin biosynthetic gene cluster. It has been shown to contribute to the assembly of the skeletal backbone of AzB. A typical non-ribosomal peptide synthase module consists of an A-PcP-C module. However, AziA2 consists of a C-PcP-C module with two active condensation domains. Knockout of the module yielded no AzB production and domain analysis of the PcP-C module led to the discovery of a new metabolite. Collection/isolation of the metabolite, using an HPLC instrument, can lead to future studies dealing with characterization of this metabolite giving insight into the activation and role of the condensation domains.

CHED 389

Design of robust LuxS activity assay protocol and synthesis of known inhibitor for inhibition assays

David J Silpa,, Keeshia Wang, Megan E. Bolitho.Department of Chemistry, University of San Francisco, San Francisco, California 94117, United States

Quorum sensing (QS) is a biochemical process used by many bacterial species to communicate via small-molecule "auto-inducers." QS Systems 1 and 2 are used to communicate within and across species, respectively. QS-2 has been shown to regulate virulence expression in many pathogens and is thus a drug-development target; LuxS, an enzyme integral to QS-2 has been identified as a target for inhibition. An Ellman's assay is employed to spectrophotometrically observe LuxS activity and has herein been rigorously optimized. This assay will be used to quantify LuxS inhibition by small molecules, including a benchmark inhibitor reported in literature for which syntheses are attempted.

CHED 390

Identification of licorice root components for prostate cancer therapeutics using triple quadrupole GC-MS

Evan S DuBose1,, Marisela D Mancia1, Michelle E Reid1, James A Campbell2, Kimberly M Jackson1.  (1) Department of Chemistry, Spelman College, Atlanta, GA 30314, United States  (2) Chemical and Biological Signature Sciences, Pacific Northwest National Laboratory, Richland, WA 99352, United States

Licorice root (Glycyrrhiza glabra), an herbal Chinese medicine, has shown medicinal uses in therapeutics and cancer prevention. Dibenzoylmethane (DBM), a small β-diketone, has been reported to be a minor constituent of licorice and a known deregulator of human prostate cancer cell cycle. Characterization of the phytochemical profiles of licorice root forms including commercially available DBM will advance our search in identifying novel reagents for prostate cancer therapeutics. Gas chromatography- triple quadrupole-mass spectrometry analysis was used for detecting DBM in licorice root extracts. DBM and all licorice forms exhibited a component at a retention time of 14.5 minutes. The major fragment ions detected were m/z 77, 105, 147, 223 and 224 at the identified retention time. Selected reaction monitoring (SRM) confirmed DBM as a minor constituent of G. glabra. This study provides a GC-MS/SRM method which helps in the identification of small trace compounds and minor components in complex biological matrices.

CHED 391

Site-directed mutagensis and spectroscopic studies of the oxygen sensing heme-PAS FixL protein

Avery Vilbert,, EuTchen Ang,, Mark Reynolds.Chemistry, Saint Joseph's University, Philadelphia, PA 19131, United States

The oxygen sensing FixL protein from Sinorhizobium meliloti regulates nitrogen fixation in the hypoxic root nodules of alfalfa plants. FixL is part of the heme-PAS and two-component histidine kinase families of biological sensors. We have examined the role of conserved Fa-helix residues in the heme domain of SmFixL* using site-directed mutagenesis and various spectroscopies. The Fa-helix variant proteins R200(A, E, Q, H), Y197A and D195A were expressed at reasonable levels and purified to homogeneity, but the R200I and Y201A variants did not express in observable quantities. Spectroscopic studies (UV-vis, CD and resonance Raman) and kinase activity assays of these Fa-helix SmFixL* variant proteins indicate that R200 and Y197 are likely important in oxygen sensing at the heme site and signal transduction to the kinase domain. These studies may help elucidate a detailed mechanism for the gas sensing heme-PAS proteins and other two-component histidine-kinase sensors in nature.

CHED 392

Save your Bible the organic way

Soham Mody,, Rachel Rigsby.Department of Chemistry and Physics, Belmont University, Nashville, Tennessee 37212, United States

Modern scientists are rigorously trying to mimic nature to solve problems with reduced toxicity and in less harmful ways. The object of the following research assignment was to use an organic substance like cinnamon oil (cinnamaldehyde), found naturally in the bark of the cinnamon tree, to fight common household pest such as mold to save our books. Cinnamon oil is industrially used as chewing gum flavoring and agriculturally as a plant pesticide against fungal growth. Previous research has shown that cinnamaldehyde acts as a non-competitive inhibitor of an essential cell wall component of yeast cell and prevents fungal growth. The aim of this research is to understand this process better and come up with a benign way to make paper antifungal.

CHED 393

Translesion synthesis of Y-family polymerase Dpo4

David Wilson,, Melissa Brulotte, Sam Lone.Department of Chemistry, Bridgewater State University, Bridgewater, Massachusetts 02325, United States

It is well understood that mutations in critical genes are responsible for a variety of diseases including cancer. Chemical carcinogens can lead to mutations by attaching to the DNA bases and interfering with the normal replication process. Replication through these DNA lesions is performed by a novel class of DNA polymerases identified as translesion synthesis (TLS) polymerases. To better understand how these DNA polymerases are able to replicate across DNA lesions, we are determining the structure and function of archaeal TLS polymerase Dpo4 bound to free radical lesion 8-oxo-7,8-dihydroadenosine (8-oxo-A). Single nucleotide template-primer extension analysis reveals that Dpo4 inserts the correct nucleotide dTTP across from 8-oxo-A lesion. We have successfully crystallized Dpo4/8-oxo-A complexes and currently, we are working on crystal optimization, cryoprotection, and diffraction data collection.

CHED 394

YfdW and YfdU are required for oxalate-induced acid tolerance in Escherichia coli

Karen E Ezelle,, John M McAfee,, Cory G Toyota.Millsaps College, Jackson, MS 39210, United States

E. coli has several mechanisms for surviving low pH stress. We report that oxalic acid, a small chain organic acid (SCOA), induces a moderate acid-tolerance response (ATR) under two conditions. Cells adapted at pH 5.5 with 50 mM oxalate and subsequently challenged in minimal medium at pH 3.0 demonstrate increased surivival. In addition, there is also a significant protective effect when cells are challenged in the presence of 25 mM oxalate at pH 3.0. We report that the enzymes YfdW, a formyl-CoA transferase, and YfdU, an oxalyl-CoA decarboxylase, are required for the adaptation effect, but are not necessary for the protective effect during challenge alone. The mechanism is not yet understood, but we demonstrate this oxalate-dependent ATR is not affected by Ca2+ depletion.

CHED 395

Investigation of the capsule polysaccharide expression pathway of Vibrio vulnificus

Joseph M Hazel,, Anahita Z Mostafavi,, Margaret A Chahoud,, Jerry M Troutman.Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC 28223, United States

Vibrio vulnificus is a gram-negative bacterium found in raw shellfish that causes more seafood-borne fatalities in the US than any other bacterium, and virulence has been linked to capsule expression. The capsule of strain M06-24 is a repeating tetrasaccharide composed of three α-N-acetyl-quinovosamine (QuiNAc) residues and one α-N-acetyl-galactosamine uronic acid (GalNAcA) residue, yet the role of individual enzymes in the expression pathway is not yet understood. The operon responsible for capsule production is believed to contain twelve genes. These genes are hypothesized to encode seven sugar modifying enzymes and the four glycosyltransferases. The proteins encoded by these genes have been isolated and purified. My work focuses on the functional identification of the proteins involved in capsule production. The pathway of enzymes responsible for the production of GalNAcA has been identified. In addition, the roles of several enzymes involved in the production of QuiNAc have been elucidated.

CHED 396

Antioxidant activities of quercetin and novel flavonoid derivatives

Scott E York,, Willibroad Miamo, Chavonda J Mills.Department of Chemistry,Physics & Astronomy, Georgia College & State University, Milledgeville, Georgia 31061, United States

Cyclooxygenase is responsible for the oxidation of arachidonic acid into prostaglandins, which are used in various functions within the body including common processes such as GI maintenance. One isoform of Cyclooxygenase, Cyclooxygenase-2 (COX-2), is specifically credited with the role of causing inflammation, and is often overexpressed within cancerous tumors.Thus, studies suggest that inhibition of COX-2 could be used to treat and prevent cancer. It is also proposed that due to the selective nature of this isoform, the inhibition of COX-2 can occur without the harmful effects of COX-1 inhibition. Aurones, a subclass of flavonoids, express COX-2 inhibitory activity by serving as scavengers of free radicals. Specifically, the flavonoid derivative, quercetin is being examined for its antioxidant activity with specific attention towards the presence of hydroxyl groups. Using DPPH as a free radical producer, quercetin, its methylated counterpart, and novel aurone derivatives were investigated for their free radical scavenging activities.

CHED 397

Oxalate-dependent acid tolerance response in Escherichia coli

Maryam N Qureshi,, Cory G Toyota.Department of Chemistry and Biochemistry, Millsaps College, Jackson, MS 39042, United States

E. coli has evolved several mechanisms for surviving low pH stress. We report that oxalic acid, a small chain organic acid (SCOA), induces a moderate acid-tolerance response (ATR) in two ways. Adaptation at pH 5.5 with 50 mM oxalate and inclusion of 25 mM oxalate in the pH 3.0 minimal challenge medium separately conferred protection: 67 ± 7% and 87 ± 17% survival after 2 hours, respectively. Combination of oxalate-adaptation and oxalate supplementation in the challenge medium resulted in increased survival over adaptation or oxalate in the challenge medium alone. Cells show significant protection after 15 min exposure to 50 mM potassium oxalate. This oxalate-dependent ATR is strongest at pH 3.0, but there is also significant, but reduced protection at pH 2.5. We theorize that this oxalate ATR could enhance the pathogenesis of virulent E. coli consumed with oxalate-containing foods like spinach.

CHED 398

Accurate measurement of protein concentrations in snake venoms using ovalbumin as a standard protein in the linearized Bradford assay

Christian E Herrera,, John J Osterhout.Chemistry and Biochemistry, Angelo State University, San Angelo, Texas 76909, United States

Accurate measurement of protein concentrations in mixtures, such as snake venom, is difficult due to the unknown extinction coefficients of a mixture and different responses to protein assays (such as the Bradford assay). The use of extinction coefficients would not be possible even if the extinction coefficients of all the individual proteins were known. Here we show that North American, Asian and African snake venoms all demonstrate approximately the same response to the linearized Bradford assay on a dry weight basis. The response of ovalbumin to the linearized Bradford assay is approximately the same as the snake venoms and different from that of other common proteins standards, such as bovine serum albumin or β-lactaglobulin. The concentration of ovalbumin can be determined spectrophotometrically, giving accurate and reproducible preparation of standard curves. The combination of the linearized Bradford and ovalbumin standards promisses a reproducible and universal assay for snake venoms.

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CHED 400

Oxalic acid and Escherichia coli

Kristin M Salmon,, Cory G Toyota, College, Jackson, MS 39210, United States

Small chain organic acids (SCOA), like acetate and benzoate, have long been used as preservatives because of their bacteriostatic properties. Interestingly, these same acids also induce protective effects in Escherichia coli cells that are subsequently challenged under low pH conditions. Here we report that increasing concentrations of oxalate (1 – 250 mM) have a bacteriostatic effect on cells grown in complex medium (pH 5.5). However, exposure to oxalate also induces an acid tolerance response (ATR) that protects stationary phase E. coli for several hours at pH 3.0. Unlike acetate and benzoate, this protective effect does not appear to be under the control of the sigma factor RpoS, also known as the master regulator of stress in E. coli. Our deletion mutant data indicate that this oxalate-dependent ATR is linked to phoQ, part of the two component PhoPQ signal transduction system, and gadE a central regulator of acid resistance in E. coli.

CHED 401

Structural and functional studies of the Y-family DNA polymerase Pol κ

Natasha Mariano1,, Jason Walsh2, Ramya Parasuram2, Mary Jo Ondrechen2, Penny Beuning2, Samer Lone1.  (1) Department of Chemical Sciences, Bridgewater State University, Bridgewater, Massachusetts 02325, United States  (2) Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, United States

Our cells are continuously attacked by chemical agents, which can lead to the formation of DNA lesions. The integrity of our DNA is vital for human survival; otherwise, we risk mutations leading to disease. Recently, the Y-family polymerases were discovered to perform replication through DNA lesions. Biochemical and structural analysis reveals that unlike the replicative polymerases, the Y-family DNA polymerases are able to accommodate the distortions presented by the lesions. Each of the Y-family DNA polymerases has unique structural components enabling them to accommodate the variety of DNA distortions created by the lesions. The N-clasp region of DNA Polκ has been described to be essential for this polymerase's ability to extend mismatched DNA. To further elucidate the importance of the N-clasp of Polκ, we used POOL and THEMATICS to predict residues essential for activity. We will present the role of the N-clasp domain in the bypass of DNA mismatches.

CHED 402

Development of a fluorescence-based assay for RNA-ligand discovery

Shapnil Bhuiyan,, Danielle N Dremann, Alain Bertous, Moninderpal Kaur, Christine S Chow.Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States

Helix 69, or H69, of the ribosome plays a key role in initiation and termination of translation. Small-molecule binding to this region could lead to inhibition of protein synthesis, an essential process throughout phylogeny. The H69 region of bacteria has been shown to bind certain peptides selectively, which may lead to new antimicrobials. The goal of this study is to identify compounds that bind to H69 by developing and using an optimized fluorescence-based assay. The assay uses TentaGel beads with bound synthetic peptides, biotinylated H69, and streptavidin-tagged quantum dots (Qdots). The interaction of H69 with the immobilized peptide is indicated through Qdot emission, which is visualized under a fluorescence microscope. The relative fluorescence value is quantified using Adobe software. In the future, the assay will be used to identify new binding ligands for H69.

CHED 403


CHED 404

Synthesis and evaluation of the glutathione-3-methyleneoxindole conjugate as a potential inhibitor of human glyoxalase I

Valerie A. Ivancic,, Edward J. Brush.Department of Chemistry, Bridgewater State University, Bridgewater, MA 02325, United States

The glyoxalase enzyme system is highly conserved among all organisms and plays a key role in detoxifying the cytotoxic metabolite methylglyoxal into lactic acid. Glyoxalase I (GxI) is considered an anticancer target because inhibiting the enzyme will result in a localized buildup of methylglyoxal, which can potentially induce cell death in those targeted cells. This research focused on an evaluation of the conjugate between glutathione (GSH) and 3-methyleneoxindole (GSMOI) as a potential inhibitor of human GxI. GSMOI were synthesized and characterized, and subsequently tested as a competitive inhibitor for both yeast and human GxI. In contrast to previous research on GSH conjugates, this work suggests that GSMOI inhibits yeast GxI through mixed inhibition instead of pure competitive. It was also found that GSMOI is an inhibitor of human GxI, and preliminary results suggest irreversible time-dependent inactivation is occurring.

CHED 405

Stoichiometric analysis of metalloproteins by simultaneous particle-induced X-ray emission spectroscopy and nuclear reaction analysis

Megan M. Sibley2,, Andrew J. McCubbin1, Paul A. DeYoung1, Graham F. Peaslee1.  (1) Departments of Chemistry and Physics, Hope College, Holland, MI 49424, United States  (2) Department of Chemistry, Clemson University, Clemson, SC 29708, United States

Particle-Induced X-ray Emission Spectroscopy (PIXE) and Nuclear Reaction Analysis (NRA) are two highly sensitive ion beam analytical techniques which probe the elemental constitution and areal density, respectively, of a sample. Using a 1.7 MV tandem electrostatic particle accelerator, these methods have been utilized simultaneously to determine the identity and stoichiometry of metal atoms within protein samples of known metal content; results indicate the technique is a useful tool which can be accurately extended to proteins of hitherto unknown metal stoichiometry. The nondestructive technique, originally developed for dried protein spots on a thin support, has been extended for metalloproteins suspended in polyacrylamide gel. This allows use of the technique in biochemical applications in which proteins are separated by polyacrylamide gel electrophoresis (PAGE). Various methods of sample preparation and gel drying have been considered. Additionally, such factors as the thickness, constitution, and possible contaminants of the gel have been investigated.

CHED 406

Alkaline phosphatase activation in the presence of trifluoroethanol solution in pH 10 carbonate vs. Tris buffer

Sam Petter,, Kayarash Karimian, Eva Csuhai.Department of Natural Sciences and Mathematics, Transylvania University, Lexington, KY 40508, United States

Enzymes typically get inactivated when presented with even minute amounts of organic solvents. However, there are a few enzymes where this is does not seem to be the case. In our study, we examined the enzyme known as alkaline phosphatase, obtained from calf intestines. This enzyme seems to be actually activated by 2,2,2-trifluoroethanol in the presence of pH 10 carbonate buffer. The focus of this experiment is to determine the dependence of enzyme activity changes on temperature during the activation of the enzyme with the carbonate buffer (pH 10) and the various amounts of trifluoroethanol. The temperatures tested were 45 °C, 65 °C, and 85 °C. The experiment was then extended by utilizing carbonate and Tris buffers, at a pH of 9, and examining their effects. We report on the buffer dependence of the activation of alkaline phosphatase in trifluoroethanol.

CHED 407

Algorithm based mutagenesis analysis of the human DNA polymerase kappa N-clasp domain

Jeremy C Maré1,, Jason M Walsh2, Ramya Parasuram2, Mary Jo Ondrechen2, Penny J Beuning2, Samer Lone1.  (1) Department of Chemical Sciences, Bridgewater State University, Bridgewater, MA 02325, United States  (2) Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, United States

The environmental carcinogen benzo[α]pyrene 7,8-diol-9,10-epoxide (BPDE) has been reported to be a major constituent in cigarette smoke and a major carcinogen responsible for lung cancer. DNA damaged by BPDE cannot be replicated by classical DNA polymerases. However, human DNA pol kappa (polκ) has been shown to perform a special type of DNA synthesis known as translesion synthesis; allowing for polκ to replicate across DNA damaged by BPDE. To obtain a deeper understanding of polκ's role in benzo[a]pyrene bypass, we have used the computational methods THEMATICS and POOL to select for residues responsible for enzymatic activity. Of significant interest is the N-clasp domain of polk, which has been shown to be essential for this polymerase's bypass ability. We have created several variants within the N-clasp domain and we are currently examining how these changes affect the ability of polk to perform bypass across DNA that has been site-specifically modified with benzo[α]pyrene.

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CHED 409

Investigation into the functionality of the E. coli sliding clamp and polymerase IV

James McIsaac1,, Philip Nevin2, Penny Beuning2, Sam Lone1.  (1) Department of Chemistry, Bridgewater State University, Bridgewater, MA, United States  (2) Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, United States

Understanding the mysteries of the molecular world is of paramount importance where it concerns the protein machinery that maintains and protects the functions of life. This project was designed to pierce the veil of this unseen world and uncover answers about the functionality of polymerase IV and the sliding clamp sub-unit of the Beta clamp. Polymerase IV is a bacterial enzyme involved in translesion synthesis. In order to understand what occurs when primer extension fails, unwanted cystines were removed and an Alexa fluorophors will be attached to detect conformational changes using single-molecule FRET. The sliding clamp works with other proteins in order to maintain their proximity to DNA and increase processivity. Mutations have been created by rearranging the position of domains within the clamp to determine the significance of a nearly identical geometry between the domains. Protein function will be evaluated using methods such as in vitro replication assays.

CHED 410

Inhibition of SbnH and select NIS synthetase enzymes in the siderophore biosynthetic pathways of Staphylococcus aureus

Allyson A Cox,, Brittany S Soto, Ian P Kelly, David J. A. Schedler, William Kittleman.Department of Chemistry and Physics, Birmingham-Southern College, Birmingham, Alabama 35254, United States

Staphylococcus aureus is one of the leading causes of hospital-acquired infections. It is also notorious for developing resistance to known antibiotics. The purpose of this research is to develop new therapeutic agents that inhibit, or eliminate, the growth of S. aureus by targeting the biosynthesis of the essential, iron-scavenging siderophores staphyloferrin A and staphyloferrin B. Transition state/multi-substrate inhibitors of the citrate-activating NIS synthetase enzymes SfnaB, SfnaD and SbnE have been designed along with a fluorinated substrate analogue of the PLP-dependent decarboxylase SbnH. SfnaB and SfnaD synthetases are located in the staphyloferrin A pathway, while SbnE and SbnH catalyze the first and second reactions, respectively, of staphyloferrin B biosynthesis. Cloning of all four enzymes has been carried out along with pilot expression and purification experiments. Synthesis of the fluorinated SbnH analogue and the enzymatic production of the SbnH substrate are underway.

CHED 411

Role for the tumor suppressor p27kip1 in cancer cell metabolism

Tyler A. Matheny,, Steven Kennedy, Robert J. Sheaff.Department of Chemistry and Biochemistry, The University of Tulsa, Tulsa, OK 74104, United States

Inappropriate proliferation of cancer cells requires the utilization of nutrients to synthesize the biomolecules needed for production of new cells. . The Warburg effect describes tumor dependency on aerobic glycolysis rather than the electron transport chain to generate sufficient ATP and shunt carbons into production of biomolecules needed for proliferation. While angiogenesis provides the tumor with a means of obtaining the high levels of required glucose, it occurs rather late in cancer progression. Thus, cancer cells might utilize other methods and metabolic pathways to obtain nutrients during pre-angiogenic tumor progression. P27kip1 is thought to function as a tumor suppressor protein via inhibition of cell cycle progression. However, a comparison of metabolic pathways in p27 +/+ and p27-/- mouse fibroblasts suggests cells lacking p27 can utilize nutrient sources other than glucose. This may provide cancers with decreased p27 protein with a selective growth advantage during the early stages of tumorigenesis.

CHED 412

Cancer cell cannibalism

Philip J Gasser,, Stephen Kennedy, Robert J Sheaff.Department of Chemistry and Biochemistry, The University of Tulsa, Tulsa, Oklahoma 74104, United States

Cancer cells must obtain sufficient nutrients for cell duplication. Late-stage tumors promote angiogenesis to obtain high levels of glucose, but early stage transformed cells cannot. To investigate how initial stage cancer cells obtain nutrients, tumor formation was recapitulated in culture using transformed H293s. These cells initially grow as a single layer of adherent cells, but once space is no longer available will grow on top of one another, forming a mass of cells (or foci) analogous to a tumor. When non confluent cells were refed with media lacking growth factors, foci formation was induced. An analysis of cell viability within the foci suggested cells attached to the plate were preferentially dying, which suggests cells within the foci mass are cannibalizing attached cells to promote tumor formation. This ability to obtain nutrients from other cells could be important for early tumor progression, and may represent a novel target for therapeutic intervention.

CHED 413

Identifying biological targets of the novel naphthoquinone adduct 12,13dihydro-N-methyl-6,11,13-trioxo-5H-benzo[4,5]cyclohepta[1,2-b]naphthalen-5,12-imine

Timothy E Nissen,, Stephen Kennedy, Robert J Sheaff.Department of Chemistry and Biochemistry, University of Tulsa, Tulsa, OK 74104, United States

The naphthoquinone adduct 12,13dihydro-N-methyl-6,11,13-trioxo-5H-benzo[4,5]cyclohepta[1,2-b]naphthalen-5,12-imine (hereafter called TU100) has been identified as a cytotoxic agent against various cancer cell lines. It can function as a topoisomerase inhibitor, but it is unclear whether this activity is responsible for its effects on cell viability. TU100 can also inhibit luciferase, a class of oxidative enzyme involved in bioluminescence. In this regard it is similar to resveratrol, a well known component of red wine associated with longevity and anti-cancer effects. To identify other potential biological targets of TU100, tissue culture cells were treated with TU100 and effects on other oxygenases like monoamine oxygenase and resveratrol targets such as Sirtuin 1 were analyzed.

CHED 414

Cloning, overexpression, and purification of octopine dehydrogenase from Argopecten irradians

Timothy Clark1,, Jennifer Miller2, Alexis Ceasrine2, William Jordan2, Maureen Krause2, Scott Lefurgy1,  (1) Department of Chemistry, Hofstra University, Hempstead, NY 11549, United States  (2) Department of Biology, Hofstra University, Hempstead, NY 11549, United States

Octopine dehydrogenase (ODH) catalyzes the final step of glucose fermentation in the bay scallop Argopecten irradians, producing octopine and NAD+ from pyruvate, arginine and NADH. Three stably maintained alleles of the ODH gene were identified in Argopecten populations in coastal areas of Long Island, on the basis of differential protein electrophoretic mobility. The alleles differ by one to three amino acid substitutions outside the active site. To determine the functional differences between them, the three alleles were subcloned into a bacterial expression vector, expressed in Escherichia coli as fusion proteins with an N-terminal affinity tag and purified by column chromatography. The affinity tag was removed by site-specific proteolysis and subsequent chromatography, yielding 10-15 mg of native enzyme per liter of culture. Preliminary data suggest that the three enzyme variants differ in their amino acid substrate preference.

CHED 415

Substrate selectivity of octopine dehydrogenase from Argopecten irradians

Jessica Spinelli,, Beena Biju, Nicholas Condiles, Scott Lefurgy, of Chemistry, Hofstra University, Hempstead, NY 11549, United States

Opine dehydrogenases comprise a family of enzymes that catalyze the final step of anaerobic glucose fermentation in marine invertebrates. This step includes the NADH to NAD+ recycling typically carried out by lactate dehydrogenase. These enzymes also catalyze formation of a carbon-nitrogen bond between pyruvate and an alpha-amino acid specific to that family member. The product is a single diastereomer with two chiral centers that is structurally similar to some clinically effective angiotensin converting enzyme (ACE) inhibitors. The bay scallop Argopecten irradians employs octopine dehydrogenase (ODH), a family member that is usually specific for arginine. To assess its selectivity for amino acids, recombinantly expressed and purified ODH was tested in vitro against a panel of amino acids. Unlike the previously studied ODH homologue in a related scallop, the Argopecten enzyme shows a relaxed amino acid selectivity that is sensitive to the assay mixture composition.

CHED 416

Glycosylation of cysteine-containing ankyrin repeat proteins: New multivalent ligands for wheat germ agglutinin

Lindsay Euers,, Michael Rodriguez, Jessica Hollenbeck.Department of Chemistry, Trinity University, San Antonio, TX 78212, United States

Multivalent interactions are characterized by the simultaneous binding of multiple ligands to one or more target receptors and can occur through such binding modes as chelation, clustering, and statistical rebinding. We have shown previously that glycosylated ankyrin repeat (AR) proteins can be used to cluster multiple copies of the carbohydrate-binding protein concanavalin A. To demonstrate that the same scaffold can be used to chelate multiple binding sites on an oligomeric receptor, we have targeted an alternate carbohydrate-binding protein, wheat germ agglutinin (WGA). WGA forms a stable homodimer with pairs of binding sites for N-acetyl glucosamine (GlcNAc) separated by 14 Å. The distance between adjacent repeats in the crystal structure of the AR domain is ~10 Å, thus glycosylated AR proteins with >2 repeats should span multiple binding sites. GlcNAc derivatives were synthesized and conjugated to pendant thiols on the AR scaffold, generating a new class of multivalent ligands for WGA.

CHED 417

Characterization and inhibition studies of the ornithine racemase involved in staphyloferrin A biosynthesis in Staphylococcus aureus

Jean D Rugamba,, Ian P Kelly, David J. A. Schedler, William Kittleman.Department of Chemistry and Physics, Birmingham-Southern College, Birmingham, Alabama 35254, United States

Staphylococcus aureus is a gram-positive bacterium responsible for numerous infections including those of the skin, heart, and soft tissue. It is one of the leading causes of hospital-acquired infections and in extreme cases can lead to death. Due to its continued development of resistance to current antibiotics there is an urgent need for new drugs to battle this pathogenic bacteria. The purpose of this research is to develop new therapeutic agents that inhibit the biosynthesis of staphyloferrin A (SfnA), an iron-binding siderophore produced by S. aureus. This research characterizes and carries out mechanistic inhibition studies of the ornithine racemase, SfnaC, located in the staphyloferrin A biosynthetic pathway. Results of characterization studies include cloning, overexpression and purification of recombinant SfnaC, results of in vitro activity assays, UV-vis spectral characterization of bound pyridoxal 5'-phosphate (PLP), and initiation of the synthesis of two mechanistic-based inhibitors, an ornithine phosphonate and a fluoroornithine analogue.

CHED 418

Inhibiting NF-κB: Peptides designed as biomimetics for the treatment of epilepsy

Candace Brooke Wood,, Tabitha N Williford, Amanda L Stewart.Department of Chemistry, Georgia Southern University, Statesboro, Georgia 30460, United States

Nuclear Factor-kappa B (NF-κB) is a transcription factor involved in many physiological processes including many neurological diseases. NF-κB regulates the expression of various proteins by binding specific κB DNA sites. One such protein expressed is the brain derived neurotrophic factor (BDNF). Overexpression of BDNF is associated with seizure activity. Some research suggests that the relationship between NF-κB and BDNF may be a key point of regulation within this signaling pathway. Peptides will be designed and synthesized to mimic the binding site of the NF-κB protein. Peptides that bind the κB DNA sequence tightly will be incorporated in inhibition studies to determine their ability to prevent recognition of κB DNA. Using fluorescence binding studies, the peptide binding affinities for the DNA κB sequence can be determined. The results will have implications for epilepsy as well as other neurological disorders.

CHED 419

Investigation of chemotaxis protein-protein interactions in Epulopiscium sp. type B using a yeast two hybrid system

Brie Levesque,, Andrew Piefer.Department of Chemistry, Hartwick College, Oneonta, NY 13820, United States

Epulopiscium sp. Type B is a large aquatic bacterium that resides in the gut of surgeonfish. From genomic data, Epulopiscium (Epulo) is predicted to have a chemotactic sensory and motility system similar to Escherichia coli and Bacillus subtilis. Our experiments are designed to test the protein-protein interactions between methyl-accepting chemotaxis proteins (MCPs) and the Che proteins, CheA (a sensory kinase) and CheW (an adaptor protein), through the use of a yeast-2-hybrid (Y2H) assay. We hypothesize based on genetic homology that Epulo chemotaxis proteins will behave in a similar fashion to their orthologs in B.subtilis and E.coli. The Y2H tests protein-protein interactions in Saccharomyces cerevisiae. Preliminary results detected an interaction between CheA and CheW. Other interactions have not yet been detected; possibly because CheW seems to be toxic to yeast. Alternatively, a CheA+CheW+MCP ternary complex might be necessary for MCP binding. Further research to explore these possibilities is ongoing.

CHED 420

Peptides designed for biomimetic studies of NF-κB inhibition

Lindsey M Burch,, Amanda L Stewart.Department of Chemistry, Georgia Southern University, Statesboro, Georgia 30460, United States

The protein nuclear factor-kappa B (NF-κB) is a transcription factor which is critical in cellular response to inflammation, apoptosis, and immune response. Inhibitor of kappa B (IκB) molecules inactivate NF-κB, keeping the protein within the cytoplasm. Phosphorylation of IκB degrades the inhibitor, allowing for NF-κB passage into the nucleus where it regulates the expression of numerous genes related to immune and inflammatory response. While NF-κB is crucial for immune response, its untimely activation and the overexpression of certain inflammatory proteins can result in various diseases such as cancer and many neurological disorders. Peptides mimicking IκB will be designed to study specific interactions that are key to binding of NF-κB by IκB. The peptides with highest binding affinities for the protein will be screened as broad based inhibitors for the NF-κB signaling pathway. Fluorescence binding studies and CD structure studies will be completed to characterize all designed peptides.

CHED 421

Synthesis of heterobifunctional ankyrin repeat proteins by metabolic labeling with azidohomoalanine

Rachel Barnes,, Jessica Hollenbeck.Department of Chemistry, Trinity University, San Antonio, TX 78212, United States

Ankyrin repeat (AR) proteins have a repetitive structure that is ideally suited for the display of multiple functional groups and/or recognition elements in a well-defined three-dimensional array. We have previously demonstrated the use of cysteine-containing AR proteins to append mannose residues to unique sites on the AR scaffold, and we hypothesized that we could extend this strategy to synthesize heterobifunctional AR proteins by incorporating “clickable” methionine surrogates at alternate sites in the protein backbone. In media lacking methionine, E. coli methionyl-tRNA synthetase will accept the non-natural amino acid azidohomoalanine (Aha), thereby incorporating a unique chemical handle at these positions. We have expressed and purified Aha-containing AR proteins from E. coli and have glycosylated the bifunctional scaffold using a combination of mannose and N-acetyl glucosamine derivatives.

CHED 422

In vitro self-assembly of type I collagen onto different substrates

Eryn K. Matich2,, Ming Fang1, Elizabeth L. Goldstein1, Brad G. Orr1, Mark M. Banaszak Holl1.  (1) Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48103, United States  (2) Division of Chemistry, Alfred University, Alfred, New York 14802, United States

Using atomic force microscopy, the self-assembly process of Type I collagen is followed at collagen concentrations from 0.5 to 100 µg/mL on muscovite mica, phlogopite mica, glass capillary tube, molybdenum disulfide (MoS2) and graphite. No fibril formation was found on MoS2 and graphite. The specific fibril patterns on mica surfaces are related to the mica crystal structure. The self-assembled collagen fibrils have a distribution of D-spacings, with an average value of 65-66 nm and a range between 55-70 nm. At 10 mg/mL, dense collagen fibrils form a gel in capillary tubes. When the gel from these glass capillary tubes is deposited on MoS2, they exhibit a D-spacing distribution similar to mica. The self-assembled collagen fibrils on various substrates showed similar D-spacing to those observed in biological tissues. This suggests Type I collagen assembly without heterotypic collagens or fibrillar cross-links is the origin of the D-spacing distribution.

CHED 423

Solvent isotope effects on DNA-protein crosslinking

Zitadel Anne Perez,, Christia A Sison, Eric D. A. Stemp.Department of Physical Sciences, Mount St. Mary's College, Los Angeles, CA 90049, United States

Oxidative DNA damage contributes to cancer and degenerative diseases. Guanine is particularly vulnerable to oxidation, creating guanine radicals which form crosslinks to proteins. Here, we investigate the solvent isotope effect on oxidative DNA-protein crosslinking reactions for the oligonucleotide 5'-AATAXTTTTGTTTGCGTGGATGGTTCTC-3' (X = 2-aminopurine, a strong photooxidant). For this oligonucleotide duplex, the amount of permanent guanine damage in the form of DNA-protein crosslinks depends on competition between back electron transfer from 2-aminopurine radical anion to the guanine radical cation and the trapping reaction, which may involve the formation of the neutral guanine radical. Crosslinking experiments using this oligonucleotide with histone H2A yielded more damage in H2O than in D2O. In contrast, in a flash-quench system where back electron transfer has been eliminated, D2O yielded more damage, consistent with greater yields of guanine radical in D2O. Taken together, these results suggest that trapping involves the deprotonation of the guanine cation radical.

CHED 424

High speed HPLC/fluorescence (HPLC/FL) analysis of serotonin and its metabolites in tissue and fluids: Applications in applied neurochemical analysis

Bridgett K. Carter,, Rebecca M. Baroody, Tyler G. Kethro, Edward J. Caliguri.Department of Chemistry, Sacred Heart University, Fairfield, CT 06825, United States

High performance liquid chromatography with fluorescence detection has been used for some time to measure Serotonin (5-hydroxy tryptophan, 5HT) and its metabolites. Here we preset separations using both 2.0 micron and 1.6 micron C-18 particulate columns. These columns should provide increased speed and sensitivity making their use more efficient. The features of these methods are showcased in initial studies involving Serotonin activity changes in the brain and body fluids of animals that have been administered statin medications as well as those that have 5HT-1A receptor deficiencies.

CHED 425

Investigations of the active site of 5, 10-methenyltetrahydrofolate synthetase (MTHFS) from Mycoplasma pneumoniae

Casey R. Wojtera,, Timothy W. Johann.Department of Chemistry, Roanoke College, Salem, Virginia 24153, United States

The enzyme, 5, 10-methenyltetrahydrofolate synthetase (MTHFS) plays a significant role in the folate metabolism of an organism. MTHFS is the only enzyme known to convert folinic acid into 5, 10-methenyltetrahydrofolate. Amino acids hypothesized to interact with folinic acid were investigated. Gene sequences of MTHFS were mutated using site directed mutagenesis. Through several transformations, induction, and various purifications, mutant enzymes were obtained and were tested kinetically. Based on inferences made from the calculated KM and kcat values, the amino acids Y122, Y123, E55, and F118 were concluded to be important for binding folinic acid in the active site and for maintaining catalytic efficiency of the enzyme. In addition, the mutation of glutamine to alanine at position 144 yielded an enzyme that bound the substrates of ATP and folinic acid weaker than the wild-type enzyme, but demonstrated a 2.74 fold increase in kcat.

CHED 426

Isoprene synthase: A key to cellular relief from toxic isoprenoid precursors in E. coli?

Jordan A Killop,, Tami Sivy.Department of Chemistry, Saginaw Valley State University, University Center, MI 48710, United States

Practicing recombinant DNA technology has shown great potential to decrease both the cost and the environmental impact of developing important prenyl-based drugs such as the anti-malarial artemisinin and tumor-suppressor Taxol. For reasons not fully understood, progress has been limited by the decreased cell growth of bacterial hosts used to produce these drugs. The cause of death is suspected to be toxicity of isoprenoid precursors. We studied the effects of decreasing the levels of the putative toxic compounds, DMAPP and IPP, by expressing an isoprene synthase from poplar in E. coli. As this enzyme uses DMAPP as a substrate to produce the volatile and releasable isoprene, we hypothesize that its activity could be used to relieve the cytotoxicity. The isoprene synthase expression was varied and paired with increased flux through a heterologous isoprenoid pathway in order to test the hypothesis and examine the influence of intermediate levels on cytotoxicity.

CHED 427

Cisplatin-induced apoptosis in HeLa cells to determine potential mechanisms for drug resistance

Mackenzie M. Shipley,, Andrew J. Piefer.Department of Chemistry, Hartwick College, Oneonta, New York 13820, United States

The purpose of this project is to study the cisplatin-induced apoptosis mechanism in HeLa cells. Apoptosis or programmed cell death occurs when molecular lesions are formed in genomic DNA. By using small-interfering RNA (siRNA), the oncogene c-Abl will be knocked down. c-Abl encodes a cytoplasmic and nuclear protein tyrosine kinase involved early in the apoptotic pathway. A colorimetric assay kit will be used to measure the amount of caspase-3 present in cells (indicative of apoptosis) before and after knockdown of c-Abl. The results of this research will determine if c-Abl is involved in cisplatin mediated apoptosis in a cervical cancer cell line and may reveal potential drug resistance mechanisms.

CHED 428

Quantitative analysis of metal ion, chlorophyll, and antioxidant activity in senescing Ginkgo biloba leaves

Ashley M. Mannix,, Virginia S. Smith.Department of Biochemistry, United States Naval Academy, Annapolis, MD 21412, United States

A vital source of antioxidants, the leaves of the Ginkgo biloba tree represent a promising field of medicinal research. A full year of Ginkgo biloba leaf extracts were analyzed to determine peak antioxidant activity via sample time delays in the Briggs-Rauscher oscillating reaction. The assays revealed that senescent (yellow) Ginkgo leaves have a higher average antioxidant activity than the green leaves, suggesting antioxidant compounds may protect against metal-ion induced oxidation after chlorophyll is gone. Metal ion concentrations were determined by performing microwave digestion in hydrogen peroxide and nitric acid followed by atomic absorption spectroscopy. Analysis of calcium, iron, and magnesium ions indicate that peak levels correlate to the senescent phase of Ginkgo leaves. Chlorophyll levels determined by UV-visible and fluorescence spectroscopy were also correlated to the levels of metal ions. The combined analysis of antioxidants, metal ions, and chlorophyll levels provide a detailed chemical profile of Gingko leaf senescence.

CHED 429

Synthesis and evaluation of alkyne derivatives of parthenolide for identification of cellular protein targets

Myungsun Shin,, Thanprakorn Chiramanewong,, Rebecca E. Connor.Department of Chemistry, Dickinson College, Carlisle, PA 17013, United States

The sesquiterpene lactone, parthenolide, is a natural product found in the medicinal plant feverfew. Parthenolide is known for its anti-inflammatory effects and potential of its amino derivatives as chemotherapeutic agents for the treatment of leukemia and other cancers. Parthenolide contains an electrophilic γ-butyrolactone functional group that will covalently modify biological nucleophiles, such as amino acids in proteins. We have synthesized alkyne derivatives of parthenolide in order to identify proteins modified by or binding to parthenolide using copper-catalyzed azide-alkyne Huisgen cycloaddition (CUAAC). The alkyne-parthenolide derivatives have been tested as reagents in CUAAC reactions with azidopropylbiotin using TBTA as the ligand. Covalent modification of model proteins by the alkyne derivatives has been used to validate the use of CUAAC. Protein targets in human acute myelogenous leukemia (THP-1) cells will be identified following cellular treatment with the derivatives, using CUAAC to append an azide-biotin tag for affinity capture.

CHED 430

Oxidative crosslinking between tRNA and protein

Bridgett Cabrera,, Pia Cartagena,, Alyson Thien,, Zitadel A Perez, Kelsey Miller, Eric Stemp.Department of Physical Sciences, Mount St. Mary's College, Los Angeles, CA 90049, United States

Oxidation of guanine can lead to DNA-protein crosslinking. Transfer RNA molecules encounter many proteins during translation and we investigated whether guanine oxidation can also produce RNA-protein cross-linking. tRNAPhe in the presence of histone or poly(lysine) was subjected to the flash-quench technique, a method known to selectively oxidize guanine. Irradiation of ethidium or Ru(phen)2dppz2+ [phen = phenanthroline, dppz = dipyridophenazine] in the presence of Co(NH3)5Cl2+ (an oxidative quencher) led to a loss in the intensity of the free band for the tRNA and a corresponding appearance of bands with lesser mobility in gel shift experiments. In addition, in the chloroform extraction assay, a drop in the 260 nm absorbance of the RNA was observed upon flash quench treatment. These results are consistent with RNA-protein cross-linking as a result of guanine oxidation and suggest that this may be another consequence of oxidative stress.

CHED 431

Effects of alkynyl-parthenolide derivatives on cellular viability, glutathione levels, and cellular signaling of human leukemia cells, THP-1

Gabriel J. DiNatale,, Rebecca E. Connor.Department of Chemistry, Dickinson College, Carlisle, PA 17013, United States

Parthenolide, a natural extract from the feverfew plant, and its water-soluble amino derivatives have been proven to be effective in killing leukemia stem cells. Parthenolide and its derivatives are capable of the covalent modification of proteins through an electrophilic α,β-unsaturated exocyclic methylene group. We have synthesized derivatives of parthenolide modified with alkyne functional groups for the identification of cellular protein targets of these electrophilic molecules. This work describes the characterization of parthenolide and our synthesized derivatives for their effects on the viability of THP-1 cells both in suspension and after differentiation into macrophages. The effect on cellular glutathione levels over time and with increasing concentration of parthenolide and our derivatives was compared to the effect produced by phorbol-12-myristate 13-acetate, a known inducer of THP-1 monocyte differentiation. Changes in cellular signaling after treatment were assayed by immunoblot for the NFκB and heat shock response pathways.

CHED 432

Characterization of Aspergillus niger cellulase for biomass conversion

Jennifer A. Hill,, Lovepreet Singh, Robert C. Steinmeier.Department of Chemistry, University of Arkansas at Little Rock, Little Rock, Arkansas 72204, United States

Enzymes capable of hydrolyzing cellulose are found in filamentous fungi and bacteria. The study undertaken was of the extracellular cellulase cocktail from Aspergillus niger which included cellobiohydrolase, endoglucanase, and β-glucosidase activities that work synergistically to break down cellulose. The effects of organic solvents on different enzyme activities were analyzed as well. Inhibition of different enzyme activities by ethanol and dimethylsulfoxide was studied using selected substrates. Compared with T. reesei, A. niger cellulase had much higher β-glucosidase activity for cellobiose or p-nitrophenyl-β-glucoside (PNPG) and also had higher activity with Avicel. Gluconolactone completely inhibited reaction with PNPG but not cellobiose. Reaction of A. niger cellulase with p-nitrophenyl-β-D-cellobioside was kinetically complex and p-nitrophenyl-β-D-lactoside was unreactive. With CMC as the substrate, inhibition of A. niger cellulase by ethanol or DMSO is more pronounced than with T. reesei. The same is true for ethanol inhibition of β-glucosidase activity with PNPG as the substrate.

CHED 433

Effects of an enaminone library with amino acid functionalities on protease activities

Kevin Thomas,, Phillip Goree, Stephen Kennedy, Robert J Sheaff.Department of Chemistry and Biochemistry, The University of Tulsa, Tulsa, OK 74104, United States

Proteases are enzymes which hydrolytically cleave peptide bonds at specific amino acid residues in proteins. They play many important biological roles associated with human disease, such as in cancer metastasis, viral infection, and certain neurological disorders. Thus, protease inhibitors make up a whole class of pharmaceutical compounds. A library of enaminones with amino acid functional groups was analyzed for its effects on protease activity. The 31 synthesized compounds underwent screening against four different purified proteases (bromelain, trypsin, chymotrypsin, and protease A) to determine their effects on proteolytic activity using BSA as a substrate. A few compounds demonstrated both activation and inhibition of protease activity, especially when utilizing bromelain. This capacity for modulating protease activity suggests that some of the enaminones might have biological activity and serve as promising intermediates for the synthesis of novel compounds with therapeutic potential.

CHED 434

Decay of guanine radical produced by the flash quench technique: Dependence upon quencher

Evelyn Carrillo,, Veronica L Torres,, Jenny Garcia,, Eric Stemp, Robert Senter.Chemistry, Mount Saint Mary's College, Los Angeles, CA 90049, United States

Oxidative damage to DNA is a causative factor in disease and guanine can be readily oxidized by the flash quench technique. Here, we compared the guanine radical decay in DNA, with the quenchers Ru(NH3)63+ and Co(NH3)5Cl2+. Using nanosecond transient absorption spectroscopy at 373 nm, the guanine radical decays within 100 µs with Ru(NH3)63+ as quencher, but persists for milliseconds with Co(NH3)5Cl2+. On a longer timescale, excitation with a camera flash produces a detectable transient species with an absorbance maximum of ~390 nm. In related studies using guanosine-5'-monophosphate, flash quench with the cobalt quencher produces a broad absorption between 300 nm and 380 nm that decays on the seconds time scale; in contrast, Ru(NH3)63+ gives no signal. These results can be explained by the lability of the Co(II) complex formed upon reduction and formation of a guanine radical that decays into another related radical species on a longer timescale.

CHED 435

Optimizing the expression of recombinant nitrobenzene dioxygenase ferredoxin from Comamonas JS765 in E. coli

Mark D Bostrom,, Matthew Neibergall, Brock Cash, Paige Murray.Department of Biochemistry, Bethel University, St. Paul, Minnesota 55112, United States

The nitrobenzene dioxygenase enzyme system (NBDOS) initiates the degradation of nitroaromatic compounds in the bacterium Comamonas JS765. The primary goal of this research project is to optimize the conditions for over-expressing the NBDOS ferredoxin component in E. coli. This report describes how the following variables impact protein expression: Media formulation, temperature, induction time, and inducer concentration. The results will advance research on the nitrobenzene dioxygenase system.

CHED 436

Electrochemical phenomena in the Venus flytrap

Chrystelle L. Vilfranc,, Alexander G. Volkov.Department of Chemistry, Oakwood University, Huntsville, Alabama 35896, United States

The total hunting cycle of the Venus flytrap consists of the following 5 stages: open state, closed state, locked state, constriction and digestion state, and the semi-open state. The opening of the trap after digestion consists of two steps: the opening of the lobes and the changing of their curvature from a concave shape to a convex shape. Each stage of the hunting cycle has different electrical characteristics. The biologically closed electrochemical circuits in the Venus flytrap are analyzed using the charge-stimulating method. If the initial voltage applied to the Venus flytrap is 0.5V or greater, changing the polarity of the electrodes between the midrib and one of the lobes will result in a rectification effect and different kinetics of a capacitor discharge. These effects are due to the fast transport of ions through voltage gated ion channels. The electrical properties of the Venus flytrap were investigated. The equivalent electrochemical circuits, within the upper leaf, were proposed to explain the experimental data.

CHED 437

System for comparing relative rates of back electron transfer and crosslinking

Christina Khorozyan,, Melissa Marquez,, Shushan Khorozyan,, Zitadel Anne Perez, Kelsey Miller, Eric Stemp.Department of Physical Sciences, Mount St. Mary's College, Los Angeles, CA 90049, United States

Electron holes produced upon DNA oxidation are mobile and can move throughout the base stack. One possible trapping reaction for guanine radicals is the formation of DNA-protein crosslinks. The fluorescent analogue, 2-aminopurine can photo-oxidize guanine and undergo back electron transfer. Titration of 2-AP with guanosine-5'-monophosphate results in quenching, consistent with redox. We placed 2-aminopurine into a DNA strand at two different distances from the nearest guanine base to determine the relative rates of back electron transfer and crosslinking to protein. Crosslinking was detected by gel shift assay. A 29-mer DNA duplex containing a 5'-G(T)nX-3' sequence was used (n=0,4 and X=2-aminopurine). Upon irradiation, no change was seen in the mobility of n=0. However, n=4 showed a decrease in free DNA bands and the appearance in lower mobility bands; in the n=4 duplex, back electron transfer, does not compete as well with the protein trapping reaction.

CHED 438

Quantitative analysis of the binding of mammalian linker histone isotopes to chromatin in vivo

Jacob Files1,, David T Brown2.  (1) Biochemistry Department, Spring Hill College, Mobile, Alabama 36608, United States  (2) Biochemistry Department, University of Mississippi Medical Center, Jackson, Mississippi 39201, United States

The linker or H1 histone is a protein that binds and compacts DNA. Recent investigations have shown that these histones are mobile proteins, constantly moving from one strand of DNA to another. This movement of the H1 histone is thought to regulate chromatin compaction. In this experiment, the mobility of different linker histone subtypes (H1a, H1b, H1c, and H1d) was measured and compared to the control (H10). To achieve this purpose, DNA plasmids were created that were contained two different H1 protein genes, each attached to a different fluorescent protein. These plasmids were introduced into mouse fibroblast cells and the cells produced the different histone subtypes that were coded for on the plasmid. The mobility of each histone subtype was determined using a method called FRAP (Fluorescent Recovery After Photobleaching). The results showed that this experimental system is superior to other methods and that there are significant differences among these subtypes with respect to their affinity to chromatin. In addition, chromatin de-compaction, which is dependent upon H1 mobility, is necessary for efficient DNA repair. Some radiation-resistant tumors have elevated levels of proteins that promote H1 mobility, therefore producing hyperactive DNA repair systems. The information and techniques developed in this experiment will be useful for understanding this phenomenon in greater detail and might provide clues for effective treatments of these radiation-resistant tumors.

CHED 439

Employing linear free energy relationships (LFERs) to deduce solvolytic reaction mechanisms

Jasbir K Deol1,, Maryeah T Pavey1,, Malcolm J. D'Souza1, Dennis N. Kevill2.  (1) Department of Chemistry, Wesley College, Dover, DE 19901, United States  (2) Department of Chemistry & Biochemistry, Northern Illinois University, DeKalb, IL 60115, United States

Substituted benzyl carbamate herbicides are synthesized using the appropriate benzyl chloroformate and a substituted benzyl amine in an inert solvent. The compound, 4,5-dimethoxy-2-nitrobenzyl chloroformate (1 ) is a fine powder. A literature survey also showed that 1 is being used as a caged precursor to the capsaicin receptor TRPV1 and the ioniotropic purinergic receptor P2X2, in which the photorelease of its active compounds allow the agonists to be administered to neuron cells. In this undergraduate research project, we analyzed the solvolytic rates of reaction of 1 in a variety of organic solvents with widely varying nucleophilicity and ionizing power values. The reaction rates at 25.0oC were determined using acid-base titrations over a select period of time. The addition of water to any pure organic solvent except 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) caused an increase in the reaction rate, hinting that water induces the leaving group to break quicker. However in HFIP the exact opposite occurs; where the addition of water decreases the rate of reaction. This suggests that 1 may follow a dual pathway which is strongly dependent on both solvent nucleophilicity and solvent polarity (H-bonding effects). This project is supported, in part, by the Delaware INBRE and EPSCoR programs ‐ supported by grants from the National Center for Research Resources‐NCRR (5P20RR016472‐12) and the National Institute of General Medical Sciences ‐ NIGMS (8 P20 GM103446‐12) from the National Institutes of Health (NIH); a National Science Foundation (NSF) Delaware EPSCoR grant EPS‐0814251; and a NSF ARI‐R2 grant 0960503.

CHED 440

Solid phase immobilization of a superoxide dismutase mimic

Edmund I Sharp,, Craig N Streu.Department of Chemistry and Biochemistry, St. Mary's College of Maryland, St. Mary's City, Maryland 20686, United States

Superoxide (O2-), one of the reactive oxygen species (ROS), is a toxic molecule produced in the mitochondria during aerobic respiration and in the immune system to kill invasive microorganisms. Given its toxicity, it must be removed to limit unwanted cellular damage. Superoxide dismutases catalyze the dismutation of superoxide into molecular oxygen and hydrogen peroxide. The presence of superoxide can be quantified by measuring the hydrogen peroxide produced upon reaction with superoxide dismutase. In the interest of developing an inexpensive flow cell for determining superoxide levels in biological tissues, an artificial biomimetic MnIII-salen superoxide dismutase was synthesized as previously described and immobilized onto magnetic beads containing amine groups. The synthesis, loading, and activity of the particles are described.

CHED 441

Structural and functional bioinformatics analysis of proteins from Candidatus Liberibacter asiaticus

Luis I Rosa2,, Nancy Arroyo3, Monica M Arroyo1.  (1) Department of Chemistry, Pontifical Catholic University of Puerto Rico, Ponce, PR 00717, Puerto Rico  (2) Department of General Science, Pontifical Catholic University of Puerto Rico, Ponce, PR 00717, Puerto Rico  (3) Department of Biotechnology, Pontifical Catholic University of Puerto Rico, Ponce, PR 00717, Puerto Rico

Huanglongbing (HLB) greening disease damages citrus crops costing millions of dollars in Asia, Latin America, the United States, and Puerto Rico, among many countries. HLB infection affects socio-economic development since there are several countries in quarantine unable to export citrus, including Puerto Rico. The disease is caused by the proteobacterium Candidatus Liberibacter asiaticus, transmitted by the Asian citrus psyllid (Diaphorina citri Kuwayama). Infection may be due to a blockade of the phloem of the plant, leading to significant accumulation of starch until it dies following obstruction of nutrients. The HLB mechanisms of interaction with citrus plants are not well understood and there are no therapies available. Initial analysis of 10 hypothetical proteins revealed that they may be involved in transport, chemotaxis, adhesion, ligand binding interactions, and metabolism. We hope our results will contribute to the advancement of research to understand the proteobacterium's pathogenicity and infectivity, and subsequent development of therapies.

CHED 442

Genetic analysis of rev variation in equine infectious anemia virus

Brandon Gines1,2,, Hyelee Loyd1, Susan Carpenter1.  (1) Department of Animal Science, Iowa State University, Ames, IA 50011, United States  (2) Department of Chemistry, Spring Hill College, Mobile, AL 36608, United States

Closely related to HIV is the Equine Infectious Anemia Virus (EIAV), a virulent pathogen of horses. Genetic variation in the regulatory protein Rev of EIAV was examined throughout a clinically dynamic disease course of an experimentally infected pony. Following infection with the virulent EIAVwyo, the pony underwent a variable disease course, including an acute fever episode at 11 days post-infection (DPI), recurrent fever episodes until 363 DPI, a prolonged subclinical period, and several late fever episodes. Viral RNA was isolated from sequential sera samples, and the rev exon 2 was amplified, cloned, and sequenced. Sequence and phylogenetic analyses indicated that Rev was under selective pressure throughout infection and suggested a linear progression of rev evolution characterized by transience and divergence. These results suggest that genetic and perhaps biological variation in rev may be a contributing factor in EIAV disease progression.

CHED 443

Delivery of paclitaxel with elastin-like polypeptides

Cassie Caudill1,2,, Jayanta Bhattacharyya3, Ashutosh Chilkoti3.  (1) Department of Chemistry, Transylvania University, Lexington, KY 40508, United States  (2) Department of Chemistry, Duke University, Durham, NC 27708, United States  (3) Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States

Paclitaxel, an anti-tumor drug that acts through mitotic inhibition, has poor solubility in water and produces undesired side effects. A new method of delivering paclitaxel with a biologically inspired polymer, elastin-like polypeptides (ELP), has been developed. Paclitaxel was chemically conjugated to the elastin-like polypeptide delivery system via a pH sensitive hydrazone bond that allows for release of the drug in the acidic environment of tumors. Drug binding, micelle formation, and solubility of the paclitaxel-elastin-like polypeptide conjugate were assessed. Cytotoxicity of the paclitaxel-elastin-like polypeptide conjugate was evaluated with a cell proliferation assay using human and mouse breast cancer cell lines. The retained cytotoxicity of the drug when bound to the delivery system and the increased solubility at body temperature suggest that delivery of paclitaxel with an elastin-like polypeptide transport system will increase effectiveness of this cancer-fighting drug.

CHED 444

Paraaminobenzamidine linked iron oxide nanoparticles for bioseparations

Jose Javier Rosado,, Osvaldo Vega, Abimael Rodriguez, Veronica Forbes, Vibha Bansal.Department of Chemistry, University of Puerto Rico at Cayey, Cayey, PR 00736, United States

Cardiovascular disorders are the leading cause of disease related death in the USA; these disorders can be treated using Plasminogen activators (PAs). The problem with this treatment is that it is highly expensive due to inefficient downstream processing of PAs. Magnetic nanoparticles (MNPs), as separation matrices, offer several advantages over other common separation matrices. The main objective of this project was to develop magnetic affinity nanoadsorbents for isolation of PAs. Iron oxide MNPs were synthesized, functionalized with aminopropylsilane, and then linked to Para-aminobenzamidine, which is known to be an affinity ligand for PA. The particles were tested for their ability to bind PA from a monocomponent system (pure PA solution) as well as multicomponent system (mammalian cell culture broth). The particles bound PA successfully in both the systems. Results showed a 200-fold pure PA preparation after the separation. The purity of the preparation was visualized through electrophoresis.

CHED 445

Quantitative determination of DNA affinity for PEGylated PAMAM dendrimer gene delivery vehicles

Kyle Odell Chamberlain,, Lisa E Prevette.Department of Chemistry, University of Saint Thomas, Saint Paul, Minnesota 55105, United States

Polycations have become popular non-viral gene delivery agents due to their easy synthesis and ability to carry large amounts of DNA. To prevent toxic side effects and aggregation, polyethylene glycol (PEG) is conjugated to the polymers to mask their charge. Unfortunately, high PEG conjugation ratios can inhibit DNA binding. To optimize a polymeric gene delivery agent's effectiveness, an ideal PEG length and ratio of PEG to positive charge must be found. This study has used electrophoretic mobility shift, isothermal titration calorimetry, and ethidium bromide exclusion assays to determine an optimal PEG length and conjugation ratio for generation 5 polyamidoamine (G5 PAMAM) dendrimer. PEG chain lengths of 750, 2000, and 5000 M.W. were conjugated to PAMAM at 1:3, 1:12, and 1:30 ratios. Results indicate greater PEG chain lengths inhibit PAMAM-DNA binding affinity at all PEGylation ratios. Furthermore, at all PEG chain lengths, binding affinity is greater at lower conjugation ratios.

CHED 446

Investigation of the potential for biofuels and other uses for duckweed in Oklahoma

Abe G. Blackburn,, Cord M. Carter,, Ricky E. Lemons, Nicholas J. Wade, Dianne Baze, Nancy L. Paiva, of Chemistry, Computer & Physical Sciences, Southeastern Oklahoma State University, Durant, OK 74701, United States

The overall goals were to investigate the potential of duckweed as a biomass source for conversion to biofuels, as well as its utility for water purification and animal feed source. Duckweed is a tiny floating aquatic plant native to Oklahoma, which grows rapidly to cover ponds, doubling its biomass every 2-7 days while removing excess nutrients from water and CO2 from air. Small (60-200 L) artificial pond cultures of duckweed were used to produce biomass under different growth conditions for analysis and comparison with natural farm pond samples. Oxygen bomb calorimetry revealed that the energy content of dried duckweed samples compared favorably to switchgrass, a major biomass crop in OK, and increases in %C correlated well with increased energy content. Growth conditions are being tested to try to induce additional starch accumulation, further increasing the %C and energy content.

CHED 447

Biomass growth and lipid extraction of Nannochloropsis oculata under natural and artificial light in the Pacific Northwest

E. Lee Brewer,, Brandon Vance, Aaron Coby.Department of Biology, Saint Martin's University, Lacey, WA 98503, United States

Fossil fuels play a significant role in the energy demands of the world and have significant environmental and ecological effects. As populations increase, more people as well as nations become dependent on these limited resources, and it becomes increasingly important to find renewable energy sources that are cost efficient, easily implemented and environmentally friendly. This experiment investigted the efficiency of growing lipid-producing algae in the Pacific Northwest under natural and artificial light. We hypothesize that the artificial light sources will promote a larger algae biomass, and that because of the intensity and wavelengths, the LED lighting system will produce the most extractable lipids from the algae strain Nannochloropsis oculata, and that utilizing energy efficient lighting sources such as LED's can make algae biofuel production a cost feasible operation which can reduce or eliminate many of the energy requirements in distribution and some of the energy requirements for growth and production.

CHED 448

Tat peptide-mediated gene delivery: Complex formation and interaction with cell-surface glycosaminoglycans

Danielle Francen,, Lisa Prevette.Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105, United States

Gene therapy consists of the delivery of foreign DNA to cells. Cell penetrating compounds, such as Tat peptide, have been shown to facilitate DNA delivery through the formation of a Tat/DNA complex. Different complex +/- ratios were tested using an electrophoretic mobility shift assay with the goal of finding the stoichiometric ratio at which Tat fully binds plasmid DNA. These results were confirmed and interaction thermodynamics were determined by isothermal titration calorimetry (ITC). Complex hydrodynamic diameter was determined in solvents of increasing ionic strength using dynamic light scattering. Positively charged Tat was found to interact electrostatically with negatively charged cell surface glycosaminoglycans (GAGs). A competitive displacement assay was conducted to find the concentration of GAG needed to completely displace DNA from the Tat/DNA complex. Results support Tat-GAG affinities measured by ITC and lend insight into potential cell uptake mechanisms of these complexes.

CHED 449

Charge density and stereochemistry affect the interaction of PAMAM dendrimer with glycosaminoglycans

Kristin J. Braden,, Lisa E. Prevette.Department of Chemistry, University of St. Thomas, 1949 Lincoln Ave., St. Paul, MN 55105, United States

Cell-penetrating compounds, such as polyamidoamine (PAMAM) dendrimer, are often attached to drugs to induce cellular uptake. We hypothesize that electrostatic interaction occurs between the positively charged primary amines of PAMAM and negatively charged glycosaminoglycans (GAGs) found on all cell surfaces to different extents. The interactions between generation 5 PAMAM dendrimer and four GAGs have been studied using isothermal titration calorimetry (ITC), dynamic light scattering (DLS), and gel electrophoresis. ITC experiments revealed the binding thermodynamics. DLS was used to confirm complex aggregation. Competitive displacement of DNA cargo from PAMAM by the individual GAGs was studied using gel electrophoresis. It has been determined that PAMAM-GAG affinity is dependent upon GAG charge density and stereochemistry. GAGs can disrupt PAMAM-DNA complexes, which has implications at the cell surface during nucleic acid delivery.

CHED 450

Understanding students' use of physical models in organic chemistry

Danielle L. Koch,, Madelyn G. Shore, Nathaniel P. Grove.Department of Chemistry and Biochemistry, University of North Carolina Wilmington, Wilmington, NC 28403, United States

Molecular model kits are a ubiquitous presence in many organic chemistry classroom. Paradoxically, many students purchase these kits yet never use them or fail to use them to their full potential. This study attempts to better understand how students use molecular model kits in organic chemistry to enhance their understand of course content and the barriers they face in so doing.

CHED 451

Identification and quantitation of cocaine on U.S. banknotes collected from the metro Detroit area by gas chromatography-mass spectrometry (GC-MS)

Yiwei Deng, Steven Akins,, Mariam Ayyash,, Marwa Ayyash, Darcy Kemter-Munson, Harkamal Jhajj, Khadija Jawad, Lyndsey Sass.Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI 48128, United States

Cocaine (benzoylmethylecgonin) is one of the most commonly abused illicit drugs in the world. Many cocaine users use a wrapped banknote to sniff this drug. Banknotes become contaminated during the abuse, exchange and storage of cocaine as well as other illicit drugs. The presence of trace levels of illicit drugs is frequently used as a part of the forensic evidence establishing a link between a suspect and these drugs. In this study, a gas chromatography – mass spectrometry (GC-MS) method for cocaine analysis was adopted for the Instrumental Analysis course at the UM-D. The method was employed for identification and quantitation of cocaine on banknotes collected from various locations in the Metro Detroit area. Cocaine was detected in 42% of the banknotes tested and the amount of cocaine on each bill was in the range of 53 to 86 micrograms.

CHED 452

Size controlled synthesis of quantum dots for biological and chemical detection

Lauren Gagnon,, Faina Ryvkin.Department of Chemistry, Emmanuel College, Boston, Massachusetts 02115, United States

Quantum dots have well-recognized applications for the detection of biological and chemical materials due to their unique optical characteristics and are capable of being synthesized in undergraduate physical chemistry courses. Hot solution decomposition is a commonly used method of CdSe quantum dot synthesis at this level. However, the current experimental procedure is limited by ineffective quantum dot size control. In an effort to modify synthesis, bottom-up approaches including hot-solution decomposition, microemulsion, and sol-gel synthesis, were investigated in terms of yield, recovery, and size control process. Products were analyzed using absorbance and emission spectroscopy to determine radial sizes. They have been used in combination with specific aptameric sensors for the detection of a variety of materials. The several new approaches to quantum dot synthesis and the creation of a quantum dot based sensor will be discussed.

CHED 453

Science demos: Science lectures beyond the board

Naomi Pierre,, Patricia Santana,, Laura Osorio, Shantell Rolle, Mayra Exposito.Chemistry, Florida International University, Biscayne Bay Campus, North Miami, Florida 33181, United States

This project aims at creating an interactive learning environment through demos that aids in the comprehension of scientific abstract definitions and concepts through the method of visualization; thus-by, the project futuristically facilitates the understanding of the bond between lab and lectures as one unit. Demos are found to be an excellent way of demonstrating chemical changes in a captivating but educational manner. Some demos, such as “Fire-Proof Balloon”, use common household objects and help emphasize the need for awareness in our everyday lives. All in all, the areas of focus include: Physics, Chemistry, Biology, Environmental Science and Biomedical Science. These demos emphasize an Inquiry-Based learning process through questions generated from the interests, curiosities and perspectives/experiences of the learner and it is a cyclic process as well through this concept, the project provides tools to the under-represented, first generation high school students pursuing a college degree.

CHED 454

Incorporating green chemistry principles into general chemistry and AP-level labs for qualitative analysis, redox titration, and enthalpy of a reaction

Samantha L. Howard,, Sally A. Henrie.Department of Chemistry, Union University, Jackson, TN 38305, United States

Many colleges and high schools across the nation are concerned about potential health hazards and disposal costs associated with typical laboratory experiments. This project focuses on developing a laboratory manual that utilizes “greener” experimental procedures for advanced placement and general chemistry courses. It also teaches students about green chemistry and the growing need for its use in chemical processes. Topics for these experiments were based on the College Board's recommendations for an AP chemistry course. Additionally, these experiments were designed to be incorporated into a web-based kit so that experiments may be safely done even in non-traditional settings. This research specifically developed laboratory experiments where students investigate qualitative analysis, oxidation-reduction titrations, and enthalpy of a reaction.

CHED 455

Investigating student anxiety within the chemistry laboratory

Zoebedeh Malakpa,, Jana Jensen, Stacey Lowery Bretz.Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States

Courses that include a laboratory session can be associated with greater levels of anxiety. In areas such as chemistry, students are asked to apply their knowledge in a hands on manner, which may not always be easy for students. Decreasing students' anxiety levels in the laboratory setting could lead to better experiences in these courses. The purpose of this study is to create a tool to measure students' anxiety levels. This survey is to be administered during the laboratory check out. The survey incorporates instruments developed by researchers in chemistry education and those with background in psychology. Responses will be collected from several chemistry courses, ranging from those for chemistry majors in general and organic chemistry, to those for non-majors, for the pre-med track, to labs designed to meet a liberal education requirement. Students will report their attitudes regarding the chemistry laboratory. Preliminary results of this study will be presented.

CHED 456

Preparation of pentamidine analogs for the treatment of human African trypanosomiasis (HAT)

Aziz Mamur,, Robert Aslanian.Department of Chemistry, New Jersey City University, Jersey City, New Jersey 07305, United States

Human African trypanosomiasis (HAT) is a parasitic disease that is endemic in 36 sub-Saharan African countries. It is 100% fatal if not treated. The early stage of the disease is characterized by flu-like symptoms. The latter stage of the disease is characterized by behavioral changes, confusion, and changes to the normal sleep cycle. This last symptom obviously led to the common name of the disease, African sleeping sickness. HAT is currently treated with several old compounds including the bis-amidine, pentamidine. However, none of these compounds has an ideal profile and most are characterized by serious side effects and poor pharmacokinetics. As part of our efforts to develop new compounds aimed at the treatment of parasitic infections, we are synthesizing heterocyclic and bicyclic analogs of pentamidine with the goal of improving activity and physicochemical properties. This poster will discuss progress towards the synthesis of those analogs and plans for future analogs.

CHED 457

Design and presentation of interactive VSEPR theory video

Haley M Snyder,, Janet G Coonce, Scott H Northrup.Department of Chemistry, Tennessee Tech University, Cookeville, Tn 38501, United States

To help students visualize the important concept of the VSEPR theory, a short educational video was created to help supplement course activities. The hypothesis for this project is that when students are shown a short, interactive video with an accompanying handout, they will perform better on related exam questions. The effectiveness of this video was tested on a total of 9 undergraduate chemistry for science majors laboratory sections of students (N=620) after a short lecture and before a hands-on model building activity. The video was shown to students (N=120) in three sections; three more sections of students (N=120) were shown the same video and given an accompanying handout. These two groups, along with a control group of students (N=110), were immediately given a short quiz over the presented material. The results from this quiz, along with two questions on the common final exam, will be presented.

CHED 458

Bilingual teaching practice and investigation in the course of “Introduction to green chemistry and chemical engineering”

Zhongping Yao,, Ying Song, Dangqing Liu, Qiu Sun, Zhaohua Jiang.Department of Chemical Engineering, Harbin Institute of Technology, Harbin, China

Bilingual teaching–an important part in the undergraduate education in China–can effectively expand the students' international vision and improve English language skills. However, there are also some practical problems and obstacles in the development of bilingual teaching mode, such as issues with using PowerPoint and writing on the blackboard in English, which is difficult for Chinese students due to the long reaction time and new vocabulary. English words used by chemistry and chemical industry professionals are complex and long. In this work we describe practices and experiences from our bilingual class “Introduction to green chemistry and chemical engineering”. The specific measures are proposed, such as previewing before class, teaching English formation for professional words, and correlating multi-disciplines systematically and harmoniously. In this way, better teaching effects are obtained. From the evaluation of teaching, the above specific measures are effective and found to be useful by both students and teachers.

CHED 459


CHED 460

Different time scales in NMR and Raman spectroscopy: Aqueous phosphate solutions from pH 1 to 14

An Nguyen,, Dac Vu,, Michelle A Steiger, Thomas B Malloy Jr.Department of Chemistry, University of St. Thomas, Houston, TX 77006, United States

An undergraduate experiment which illustrates the difference in NMR time scales vs vibrational Raman spectroscopy time scales has been developed and refined over several years. The experiment comprises measuring the 31P spectra and Raman spectra of phosphate solutions at constant total phosphate concentration from pH 14 to pH 1 in ~0.5 pH increments with an Anasazi Eft-60 FTNMR instrument and a Delta Nu Advantage 633 Raman spectrometer. Details of the experiment, including some of the considerations dictated by the instrumentation, will be presented. This has been developed as a physical chemistry experiment and as a special project for freshman students.

CHED 461

NMR experiments for freshmen

Hoa Tran,, Nicholas Zaibaq,, Dac Vu,, Cesar Trivino, Elizabeth Maccato, Joveline Ollero, Dipa Balsara, Elizabeth Kuncewicz, Lara Al-Fady, Olivia Durr, Thomas B Malloy Jr.Department of Chemistry, University of St. Thomas, Houston, TX 77006, United States

The sophomore organic course is normally the first time students at St. Thomas encounter NMR. The last several years have seen the use of the Anasazi Eft-60 FTNMR incorporated in organic, inorganic, instrumental, biochemistry and physical chemistry laboratory courses. Magnetic resonance is a key technique in structural chemistry, biochemistry, biology and medicine. In this freshman program, selected students learned some of the fundamentals of NMR, the operation of the instrument and the interpretation of some proton spectra. The concepts addressed included chemical shifts, simple spin-spin splitting patterns, the effect of exchange reactions, the quantitative application of NMR, and the use for NMR to elucidate molecular structure. The program relies on the mentoring of freshman students by upperclassmen. This poster discusses some of the experiments developed and the principles mastered by the students.

CHED 462

Validation of qNMR analysis of purity of ethanol: An undergraduate chemistry laboratory experiment

Karl S. Mueller,, Peter T. Bell, William L. Whaley, Linda D. Schultz.Department of Chemistry, Geosciences, and Environmental Science, Tarleton State University, Stephenville, TX 76402, United States

Although Nuclear Magnetic Resonance Spectroscopy (NMR) is usually considered a qualitative technique, quantitative NMR (qNMR) spectroscopy can be used as an analytical tool by utilizing integration areas of species present in spectra of compound mixtures. The quantity of an unknown is determined at the per cent level by comparing the relative integration area of the unknown to that of a known amount of a standard. In this lab experiment, 1H NMR spectroscopy is used to determine the purity of an unknown ethanol sample using dimethyl sulfoxide (DMSO) as the internal standard and D2O as the NMR solvent. The experiment was tested in a Quantitative Analysis Laboratory in fall, 2012. Five students analyzed unknown mixtures over a concentration range of 65% to 95% to which water was added as an impurity. Relative average per cent error was less than 2% and a plot of experimental v actual concentration was linear.

CHED 463

Construction of the surface chemistry course for different teaching students

Zhaohua Jiang,, Zhongping Yao, Li Zhao, Li Liu, Jiupeng Zhao, Yuyan Liu.Department of Chemical Engineering, Harbin Institute of Technology, Harbin, China

Harbin institute of Technology of China is engaged in building an interface chemistry course group to meet the needs of students at different levels (undergraduates, masters and doctoral students). This course group is constructed, based on the basic principles of interface chemistry as the course core and the universal surface phenomena as the course axis; with the aim to cultivate the students with different levels to analyze and solve the problems of the surface science in terms of surface view. The common basic principles of interface chemistry is built as the shared platforms, the course models with different depths and breadth are built based on relationships of the specialty and the discipline. We have established three courses as follows: “applied surface chemistry” for the undergraduates, “surface physical chemistry” for masters students and “physical chemistry of solid surface” for doctoral students.

CHED 464

Tennessee women in chemistry: The bio project 2.0

Rachel Davies,, Judith Iriarte-Gross.Department of Chemistry, Middle Tennessee State University, Murfreesboro, Tennessee 37132, United States

Tennessee women are currently underrepresented in many STEM fields, including chemistry. In Tennessee, possibly due to a more conservative culture, the history of women in STEM is especially inaccessible. Recognizing that role models, especially those that share similar backgrounds, are a major influence on the career choices of women and girls, we have created The Bio Project, an effort to promote women role models in STEM from Tennessee. For this project, we have identified and researched Tennessee women in STEM, focusing on their achievements and challenges. We then conducted a survey to ascertain the baseline awareness level of these women among Tennesseans, and found that there was little to no awareness of their names, let alone their achievements. Using these data, we will be able to assess our progress and efficacy as we promote these role models in the future.

CHED 465

Chocolate as a basis for teaching students

Catherine M Reed,, Maria J Schroeder.Department of Chemistry, US Naval Academy, Annapolis, MD 21402, United States

While all students recognize chocolate, most are unfamiliar with its ingredients, processing methods, and unique physical properties. The developed investigations are centered on the structure/property relationships in chocolate illustrating that macroscopic properties are related to the microscale structure and behavior of molecules. One main area of focus is the thermal properties of chocolate. The fat molecules (cocoa butter) in chocolate are polymorphic, and the presence of certain crystal forms of cocoa butter greatly affects chocolate's physical properties. Differential Scanning Calorimetry (DSC) is used to characterize the thermal properties of various chocolates and map the crystal formations. Chocolates containing various types and sizes of crystals are prepared, and their properties, through tastings, are related to microstructure. Other areas of development include chocolate tempering, crystal formation through nucleation, and cold extrusion of chocolate. Examples of the classroom activities as well as the DSC experiment suitable for advanced students will be presented.

CHED 466

Fermentation experiments to spark college student interest

Stephen C Meidus,, Maria J Schroeder.Department of Chemistry, US Naval Academy, Annapolis, MD 21402, United States

Beer is fascinating to study from both a chemical and biological perspective. There are also issues involving processing and storage relevant to engineers and food scientists. With a steady decline in college students pursuing STEM majors, laboratory experiments involving the beer fermentation process could spark student interest and illustrate some possible future career paths. The developed experiment involves utilizes fermentation to produce high ethanol content products, which could be used in alternative fuels. Using the beer fermentation process as the starting point, students will study various yeasts, sugars, and experimental conditions, and determine which will lead to high ethanol content. Students will also learn about yeast fermentation and factors that control this process as well as proper sampling procedures. The ethanol content of the products will be quantified by gas chromatography. The experiment, a supplies list, safety precautions, and suggestions for laboratory implementation and student activities will be presented.

CHED 467

Undergraduate kinetics laboratory experiment: The catalytic degradation of common food dyes using the FeIII-TAML system

HanByul Chang1,, Dwight Thusdy1, Terrence Collins2.  (1) Department of Chemistry, Gordon College, Wenham, MA 01984, United States  (2) Department of Chemistry, Carnegie-Mellon University, United States

The FeIII-TAML (Tetra-Amido Macrocyclic Ligand) catalysis system has been successfully used for the degradation of a variety of pollutants through the activation of hydrogen peroxide. In addition to showing great promise for field applications, TAML catalysis also provides an excellent model system for undergraduate teaching labs. This study focuses on the TAML-catalyzed decay kinetics of common FD&C food dyes. The peroxide and food dyes used in this experiment can be purchased in grocery stores, and are both environmentally and budget friendly. The teaching lab experiment involves the complete determination of the rate law under various conditions, specifically those in which relatively large TAML or peroxide concentrations facilitate the determination of simple observed kinetics. Different dyes exhibit very different degradation kinetics allowing for the exploration of multiple aspects of chemical kinetics. In addition to serving as a didactic kinetics experiment, this lab also provides an excellent introduction to green chemistry principles.

CHED 468

Art as a context for inquiry-based learning in chemistry education

Colleen Fisher,, Steve Gravelle.Chemistry, St. Vincent College, Latrobe, PA 15650, United States

The goal of this study was to use art as a context for inquiry-based learning in secondary and undergraduate chemistry classrooms and labs. Inquiry-based learning is a strategy that can be used to engage students to increase interest in science classes, particularly for non-science majors. By incorporating art, laboratory experiments may appeal to students not generally interested in science by showing a real-world application of the techniques used. This experiment focuses on the study of inorganic pigments used in paintings throughout history. Some of the pigments studied were purchased from an art supply company; others were synthesized in the lab. Physical observations and chemical tests were performed to aid in pigment identification. In addition, various microscopic and spectroscopic techniques, ncluding polarized microscopy, UV-visible absorbance, and UV-visible fluorescence, were explored. Using the information collected through analysis, a laboratory experiment was designed for use in a high school level or non-majors course.

CHED 469

Physical chemistry laboratory experiment: Measuring the speed of sound using nitrocellulose

Brandon A Burnette,, Karl A Reyes, Karen S Molek.Department of Chemistry, The University of West Florida, Pensacola, Florida 32514, United States

The speed of sound was experimentally determined through various gases and under several temperature conditions using a machined vacuum apparatus designed using SolidWorks. Nitrocellulose, a low order explosive, was synthesized and ignited to generate the sound-wave. A pair of microphones, in combination with custom made amplifiers and a Tektronix TDS 210 oscilloscope, measured and collected the speed of sound data. Measurements were collected in Argon, Carbon Dioxide, Helium, Nitrogen, and atmospheric gases at ambient and reduced pressure (760 to 1.0x10-4 torr), as well as ambient and several reduced temperatures (25 to -20 °C). The vacuum tube was cooled using liquid nitrogen in combination with a layer of pipe insulation. This data was compared to previously reported literature values to confirm accuracy. Results from the aforementioned experiments will be presented.

CHED 470

Sonneborn Refined Products internship experience

Allison Abbey1,, Clay Rosoc2, Susan Yochum1.  (1) Department of Chemistry, Seton Hill Univeristy, Greensburg, PA 15601, United States  (2) Sonneborn Refined Products, Petrolia, PA 16050, United States

This presentation discusses an internship experience at Sonneborn Refined Products in Petrolia, Pennsylvania. The history of the company is explained, along with experiences in the three main laboratories. The laboratories are: barium and sodium sulfonate, petrolatum and microcrystalline wax, and white mineral oil. Sodium Sulfonates are discussed most in depth, explaining what they are and focusing on properties and uses in the chemical industry. White mineral oil and microcrystalline waxes are briefly explained and will be centered on their various applications.

CHED 471

Spectrophotometric determination of acetaminophen content and release time from over-the-counter gel capsules

Diana M. Cedillo,, K. Christopher Smith.Department of Chemistry, University of Texas-Pan American, Edinburg, TX 78539, United States

Acetaminophen is a commonly used over-the-counter medicine counted on for quick alleviation of pain symptoms. This lab experiment allows for the spectrophotometric analysis of the total amount of acetaminophen as well as the rate of release of acetaminophen from commonly advertised gel capsules using a system involving the oxidation of acetaminophen by iron(III) ions followed by the complexation of the resulting iron(II) ions with 1,10-phenanthroline to form a deep red-orange colored complex. The colored complex is monitored, and by using a calibration curve and Beer's Law, the total amount of acetaminophen and the rate of release of acetaminophen are determined. This poster will describe the experiment in more detail, as well as the results of trials of the experiment with general chemistry students.

CHED 472

Convenient portable demonstration modules

Robert G Maglott,, Rachel N Mason.Department of Chemistry, The University of Texas of Tyler, Tyler, TX 75799, United States

Chemical demonstrations can generate excitement about learning science and provide concrete visual reinforcement of abstract concepts. Sometimes preparing, transporting and setting up the demonstrations discourage instructors from classroom or community event demonstrations. Our goal was to reduce the inconvenience factor by providing a set of reliable experiments which could be easily and safely transported and used in non-science venues with minimal preparation efforts. We created a set of plastic shoeboxes containing all the resources required for the demonstrations. While most chemicals are not stored in the shoeboxes, appropriately sized and labeled containers are. The lid of the shoebox contains an inventory, the experiment procedure and the expected outcome. Also included is an explanatory handout geared to the 6th-8th grade level. Preparation is thus limited to obtaining the needed chemicals. In most cases the use of dedicated equipment has also reduced the clean-up burden.

CHED 473

Exploring energy through chemistry at Carroll University

Elizabeth Ebensperger,, Jamie Platz, Katelan Hall, Michael Harland, Gregory Marks.Deparment of Chemistry and Biochemistry, Carroll University, Waukesha, Wisconsin 53186, United States

In order to promote both Carroll University's and American Chemical Society's theme of energy, our chemistry club sponsored events focused on energy. Our goal was to educate both science and non-science individuals about how energy is involved in different aspects of chemistry and their lives. Going beyond the college level, we also invited classes from local elementary and high schools to join us. We started by explaining and demonstrating the different types of energy. We then focused on heat, light, and electrical energies by putting on demonstrations such as “genie in a bottle,” chemiluminescence, and making a lemon battery. We also discussed food energy by doing peanut calorimetry and making liquid nitrogen popsicles, which demonstrates loss of heat. Through the theme of energy, we were able to do our part in educating people in chemistry, as well as bring members of the community and campus together through science.

CHED 474

Five-part purification of an oxidoreductase from unicellular algae: An undergraduate biochemistry laboratory

Bahinah Callahan,, Allyson McDonald, Betsy Leverett.Department of Chemistry, University of the Incarnate Word, San Antonio, TX 78209, United States

A series of five experiments for biochemistry laboratory featuring the purification and characterization of glutathione reductase (GR) from unicellular algae is described. The experiments are demonstrated using the marine diatom, Phaeodactylum tricornutum, and the freshwater green alga, Chlamydomonas reihnardtii, as sources for the enzyme. The algae are grown economically using ethanol-sterilized glassware and air tubing, with aeration provided by an aquarium pump. This GR purification introduces unicellular algae as a study subject, and exemplifies techniques in ion-exchange and affinity chromatography, size-exclusion techniques, dialysis, and enzyme activity analysis.

CHED 475

Development and preliminary analysis of the ACELL orientation to laboratory instruction survey (OLIS)

Misha Asif1,, Akanksha Sharma1,, MaryKay Orgill1, Thomas J. Bussey1, Nathan Barrows2, Allison Kay2, Megan Robb2, George M. Bodner3, Barbara L. Gonzalez4.  (1) Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, NV 89154-4003, United States  (2) Chemistry Department, Grand Valley State University, Allendale, MI 49401-9403, United States  (3) Department of Chemistry, Purdue University, West Lafayette, IN 47907, United States  (4) Department of Chemistry and Biochemistry, California State University, Fullerton, Fullerton, CA 92831, United States

As a component of the 2012 Advancing Chemistry by Enhancing Learning in the Laboratory (ACELL) summer workshop, we developed the Orientation to Laboratory Instruction Survey (OLIS). This survey was designed to assess workshop participants' experiences and attitudes toward learning and teaching in the laboratory environment—including their views of inquiry-oriented laboratory teaching strategies—both before and after the ACELL workshop. The development of the OLIS was informed, in part, by published surveys, reports of students' views of inquiry-based laboratories, and instructors' misconceptions about inquiry-based teaching. In this poster presentation, we will discuss the development and implementation of the OLIS. In order to identify any changes in participants' instructional beliefs that may have occurred as a result of participating in the workshop activities, we will compare participants' pre-workshop survey responses with their post-workshop responses to the OLIS. We will also discuss future plans for the development and refinement of the OLIS.

CHED 476

Influences of life experiences on women's science career decision-making across generations

Tori Quist,, Dawn Del Carlo.Department of Chemistry and Biochemistry, University of Northern Iowa, Cedar Falls, IA 50614-0423, United States

Previous research has shown several factors including self-efficacy affect women's choices of majors and careers (Grunert and Bodner, 2011). Most research has focused on a small age range of women, mainly from the completion of their undergraduate degree through the very early stages of their career. This qualitative study explored the differences in life experiences of women from diverse generations who have chosen to pursue science at a primarily undergraduate institution (PUI). Participants in the study included women beginning their science undergraduate degree through women well into their science careers. Participants completed personal statements and in-depth interviews which explored past choices as well as current perceptions of the results of those choices. Results indicated that the primary factors that influence women's career choices were their accomplishments and goals, challenges, confidence, motivation, support, and interest in science. Women's stories about their specific challenges, support, and interest in science will be presented.

CHED 477

Nitrate and phosphate analysis by ion chromatography: Teaching and assessing analytical skills of introductory students

Elizabeth J. Childress,, Shelly B. Bradley, Liz U. Gron.Chemistry, Hendrix College, Conway, Arkansas 72032, United States

We use ion chromatography as a green tool to teach basic analytical skills to our very greenest introductory students. This experiment introduces General Chemistry students, in their fourth laboratory day, to volumetric analysis by creating a standard series from a stock solution. Student solutions are analyzed by ion chromatography and the students create calibration curves to calculate the concentration of environmental nitrate or phosphate samples. Although students are graded on a traditional laboratory report, we want to assess the laboratory effectiveness as a starting point for teaching analytical skills. Students' laboratory work is evaluated by examining linearity and slope of their calibration curves while students' conceptual understanding is evaluated using concept maps.

CHED 478

"Greener education": Green chemistry in the high school curriculum

Steffani Zuraw,, Jason Vohs.Department of Chemistry, Saint Vincent College, Latrobe, Pennsylvania 15605, United States

The importance of educating today's students on the awareness of green chemistry has become a grand subject of interest in the world of education. By use of the twelve principles of green chemistry, the green mass metrics, both intertwined with the holistic green star analysis, the assessment of the greenness of the synthesis of acetylsalicylic acid, aspirin, was conducted through various synthesis routes, including the variation of reaction conditions, catalysts, and reagents. Using the green assessments of these reactions, a secondary education laboratory procedure for the synthesis of acetylsalicylic acid was devised along with a brief text concerning general information on green chemistry and its development in the world. Students are instructed to calculate and analyze the mass metrics for comparisons of the greenness of multiple performed aspirin synthesis routes. A suggested area of implementation of green chemistry through this laboratory procedure is provided for the high school chemistry curriculum.

CHED 479

Greener dehydration chemistry: Montmorillonite clay-catalyzed dehydration of alcohols

Rachael M. Albury,, Justin L. Andrews,, Irvin J. Levy.Department of Chemistry, Gordon College, Wenham, MA 01984, United States

Traditionally, the synthesis of alkenes from alcohols has been catalyzed by concentrated mineral acid at high temperatures. Montmorillonite clay shows promise as a much greener and safer substitute. In a continued effort to demonstrate the viability of a Montmorillonite KSF clay catalyzed method as a greener alternative to the traditional method, the clay and mineral acid catalyzed methods were analysed and compared with respect to yield, regioselectivity and the versatility of the method when applied to several different alcohols. Initial results indicate that, for some alcohols, regioselectvity for formation of the product is improved with the clay-catalyzed approach.

CHED 480

Implementing green chemistry practices in the traditional undergraduate organic laboratory

Jamie L Resnick,, Robyn M Hyde.Department of Chemistry, Westminster College, Salt Lake City, Utah 84105, United States

The scientific community is striving to find energy efficient chemical processes that limit environmental hazards and harmful waste products in industrial settings. Until recently, the undergraduate laboratory has been overlooked as an environment that would benefit from the implementation of these industrial discoveries. Such changes would not only reduce hazards and energy consumption, but also provide an opportunity to teach chemical consciousness. Current literature on green chemistry was evaluated to identify adaptations that could be implemented. The initial goal of this project was to maintain the same educational focus of the labs, while making changes that would reduce the use of environmentally unfriendly solvents. Specifically, efforts were aimed at adopting solvent-free syntheses and modifying purification techniques. Additionally, laboratories were modified to utilize compounds that are synthesized by students the previous year. Evaluation of success included the consideration of robustness, cost, yield, purity, efficiency and the demonstration of specified learning objectives.

CHED 481

Antioxidant profiling experiment for undergraduate biochemistry

Damaris Delgadillo,, Kaela Caballero, Betsy Leverett.Department of Chemistry, University of the Incarnate Word, San Antonio, TX 78209, United States

A series of antioxidant profiling experiments for undergraduate biochemistry laboratory is described. The antioxidant status is estimated for several species of unicellular algae by analysis of cell lysates for peroxidase activity, superoxide scavenging, and total antioxidant capacity. This series may also be used to compare antioxidant activity in a single species under variable growth conditions of salinity, available nitrogen, and temperature. These experiments are designed to exemplify concepts in redox biochemistry, to familiarize students with enzyme analysis, and to introduce the theory and practice of luminescence techniques in biochemistry.

CHED 482

Hypoxia induction in unicellular algae: An undergraduate biochemistry laboratory

Kaela Caballero,, David Coleman, Betsy Leverett.Department of Chemistry, University of the Incarnate Word, San Antonio, TX 78209, United States

A series of experiments is described which demonstrates metabolic responses to hypoxia in unicellular algae. Algae are cultivated in commercially available media, and a system for gas delivery allows for four different oxygen conditions to be maintained. Induction of hypoxia is demonstrated by changes in selected metabolites and alterations in nitrogen metabolism and the citric acid cycle enzymes. These experiments provide an illustrative tool in discussions of aerobic and anaerobic metabolism, glycolysis and the citric acid cycle.

CHED 483

Synthesis, characterization, and catalysis of zeolite-based iron amino acid complexes

LaQuita M. Holt1,, L. Shannon Davis2.  (1) Department of Chemistry, Georgia Southern University, Statesboro, GA 30460, United States  (2) Department of Physical Sciences, Pensacola State College, Pensacola, FL 32504, United States

There are numerous naturally occurring enzymes that oxidize chemical compounds, such as methane, into more industrially useful chemicals, such as methanol. Mimics of these enzymes based on iron amino acid complexes supported in zeolites have been synthesized and their catalytic activity determined. The oxidation of benzyl alcohol produced benzaldehyde in stoichiometric quantities. Future work includes examining these materials for the oxidation of other substrates such as phenol, vanillin, cyclohexanol, and 1-hexanol.

CHED 484

High school students comprehension of stoichiometry using ratio and proportions

Patrick R. Escott,, Cynthia P. Guevara,, Maritza Silva, Michael F. Z. Page.Department of Chemistry, California State Polytechnic University, Pomona, Pomona, California 91768, United States

In high school level chemistry classes, many students have a difficult time understanding the chemical theory behind stoichiometric problems. Teachers often use multiple approaches to improve student problem-solving strategies. A traditional method employed by many instructors to solve these types of problems is known as Dimensional Analysis (DA), which focuses on the cancelation of units. There is an alternative method known as Ratio and Proportions (RAP), which emphasizes the relationship between the molar ratio, molar mass, and the balanced equation. In this study high school chemistry teachers incorporated the RAP method to teach stoichiometry rather than their traditional method of DA. This study will help determine which of these two methods results in a deeper understanding of stoichiometry by comparing student performance on in-class assessments, district wide assessments, and state standardized exams.

CHED 485

Ongoing analysis of interactions and argumentation during process oriented guided inquiry learning (POGIL) in general chemistry

Meredith Frazier,, Theodora Bairaktaris, Carolyn L. Draus, Patrick L. Daubenmire.Department of Chemistry, Loyola University Chicago, Chicago, Illinois 60626, United States

Prior research has identified discrete student interactions characterized as phases and bridges during POGIL general chemistry instruction, which uses group activities to foster constructivist learning via investigation of data, formation of trends/relationships/conclusions and application of learned concepts to new situations. As a well-established model developed for practical reasoning, the Toulmin Model of Argumentation reflects scientific thinking effectively. This research analyzed video transcripts of POGIL based general chemistry classes, coding for both the POGIL Phases & Bridges interactions and the Toulmin Model in order to characterize the overlap between the two. Levels of Toulmin arguments found in the group's dialogues were used to assess the overlap of POGIL instruction and their use of scientific thinking. Assessment of when different levels of argument were taking place served as evidence to support claims about POGIL interactions vis-à-vis expert thinking.

CHED 486

Combining FTIR spectroscopy and the Vernier GC for the analysis of a binary mixture: A general chemistry investigation

Logan Schmitz,, Kimberly Gerling, Joseph M. Fritsch, David B. Green.Department of Chemistry, Pepperdine University, Malibu, CA 90263, United States

We present a laboratory investigation in which a binary mixture of organic compounds are analyzed first by FTIR spectroscopy to identify the predominant functional groups possessed by the components in the mixture, followed by the determination of the components of the mixture after gas chromatographic separation using the Vernier Mini GC. The components are identified by comparison to authentic standards. Students gain experience in functional group elucidation, selecting operating conditions for a gas chromatographic separation, and operating a simple gas chromatograph early in their academic career. To our knowledge, this represents the first reported coupling of the methods of FTIR spectroscopy and the Vernier GC in the traditionally first-year chemistry course.

CHED 487

Concentrations of nitrogen dioxide as distance increases away from a highway

Emilia Ben,, Michael Schuder.Department of Chemistry, Carroll Univeristy, Waukesha, WI 53186, United States

Concentrations of NO2 were determined at various sites at Carroll University's Greene Field Station in southeast Wisconsin. Palme's passive diffusion tubes were mounted to find concentrations of NO2 as distance increased away from a highway. The absorbent, triethanolamine (TEA), was applied to the stainless steel meshes fixed within the diffusion tubes. TEA converted NO2 molecules into nitrite anions. The nitrite anions reacted with sulphanilamide to form a diazo cation which reacts with N-1-naphthyl ethylene diamine and will form a conjugated azo dye. The solution of the conjugated azo dye has absorption at 540 nm.

CHED 488

Simple and facile hydrogenation of ethyl trans-cinnamate: An undergraduate organic chemistry laboratory experiment

Hamid Yazdekhasti, Michael Castaldi,, Catalina Adorno,, Enhui Chen, of Chemistry, Saint Peter's University, Jersey City, NJ 07306, United States

A simple and facile hydrogenation of ethyl trans-cinnamate has been developed and carried out using ammonium formate as a hydrogen source in the presence of palladium on carbon (Pd/C). The reaction takes place at room temperature and atmospheric pressure without the need for special equipment. This experiment will serve as a practical addition to an undergraduate organic chemistry laboratory

CHED 489

Creation of a fiber database using micro-spectrophotometer/FTIR

Samuel Yatzkan,, Sherry T. Brown.Department of Physical Sciences, York College of Pennsylvania, York, PA 17403, United States

The identification and classification of fibers is very important to the field of criminal investigation. By examining fiber evidence found on clothing, chairs, rugs, and similar items, a possible match could link the victim to the crime scene, and to the suspect. Using an Excalibur 3100 FTIR with a Varian UMA600 Microscope attachment I constructed a fiber library in house that will be used by forensic classes at York College of Pennsylvania for the analysis of mock crime scene evidence. The fabric swatches I used as a source of the fibers, was created by Kathryn Hatch and purchased through Textile Fabric Consultants, Inc. The Excalibur 3100 FTIR with Varian UMA600 Microscope attachment not only allows for recording the infra-red spectrum of a fiber, but a visual image of the fiber can be captured as well. Using micro-spectrophotometer FTIR, students will become familiar with current instrumentation as well as how the identification of fibers is done.

CHED 490

Detecting the presence of gunshot residue of a 9mm handgun equipped with a suppressor

David J Millard,, Sherry T Brown.Department of Physical Sciences, York College of Pennsylvania, York, Pa 17403, United States

One of the harshest penalties in the American federal system today occurs when one is found in possession of a homemade device that muffles the sound of a gunshot, also called a suppressor; this is why the United States Government has strict guidelines pertaining to obtaining a suppressor. With gun violence being a major issue in recent years, a study was performed to detect gunshot residue with different means of suppression. A 9 millimeter semi-automatic handgun was fired into white cotton T-shirts, at eight different distances ranging from contact to 36 inches. A control of the unsuppressed handgun was fired first, followed by the firing of a commercially sold suppressor on the same gun. The homemade suppressor, 20 fl oz plastic soda bottle, was then attached to the muzzle of the handgun. The shirts were tested by inductively coupled plasma (ICP) for trace elements in the gunshot residue.

CHED 491

Detection of blood using hemascein and fluorescein

Amanda K Lagace,, Sherry T Brown.Department of Physical Sciences, York College of Pennsylvania, York, Pennsylvania 17403, United States

The detection of blood at crime scenes, when not easily detected by the eye, can be of great value. The purpose of this study is to test the effectiveness of using Hemascein and fluorescein in detecting latent blood stains. This experiment will use Hemascein and fluorescein on varying dilutions of blood samples in order to test their sensitivity based on the reaction time of the compounds. (The companies who manufacture these detection materials will be referenced.) Blood samples that have been combined with the Hemascein and fluorescein will also be tested with various presumptive color tests to determine the effect of these compounds on the tests. This experiment will be rewritten as a component of a laboratory experiment for students taking advanced forensic science courses.

CHED 492

Identification of inks by thin-layer chromatography and high-pressure liquid chromatography

Nicole Dixon,, Sherry T Brown.Department of Physical Sciences, York College of Pennsylvania, York, Pennsylvania 17403, United States

In document analysis, ink identification is an important part of identifying the possible tool and then eventually identifying the writer of the document. This same process can be used to prove the validity or fraudulent nature of a document. A common type of ink used by everyone sometime in their life is that of a ballpoint pen. By using the methods of thin-layer chromatography and high-pressure liquid chromatography, the purpose of this experiment was to identify chemical properties of the inks of popular brands of ballpoint pens. This work was then developed into a laboratory exercise for students in a capstone course in and undergraduate forensic science program.

CHED 493

Establishment of an infrared and ultraviolet drug library for use in an advanced forensic course

Kathleen A Vautier,, Sherry T Brown.Department of Physical Sciences, York College of Pennsylvania, York, PA 17403, United States

Drugs cause both physical and mental impairment. These factors greatly influence behavior that can lead to criminal activity. The easy acquisition of drugs can be the lone cause of criminal activity. It is important to have correct identification of drugs so that this criminal activitiy is verified. Body fluids, blood and urine particularly, are analyzed for the presence of drugs to determine if these were factors in the activity. Many different chemical instruments and techniques are used to analyze powdered substances or pills found at a crime scene or in someone's possession. Up until now, there has been no reference library for undergraduate students and faculty at York College of Pennsylvania to use when analyzing drugs that were acquired from mock crime scenes. This study used infrared and ultraviolet instrumentation to analyze many common drugs, some considered 'street' drugs and other pharmaceuticals. Spectra will be saved for future use for undergraduate students. Several pills composed of multiple drugs were also examined to determine if each drug was detectable.

CHED 494

Student perspective of and outcomes from the 18th Conference of Parties of the United Nation framework convention on climate change

John P Siller1,, Gregory P Foy1, Keith E Peterman1, Marla Bianca2, Diane W Husic2.  (1) Department of Chemistry, York College of Pennsylvania, York, Pennsylvania 17403, United States  (2) Department of Biological Sciences, Moravian College, Bethlehem, Pennsylvania, United States

In an effort to encourage youth involvement in promoting climate change literacy, the American Chemical Society sponsored four student members to participate in the 18th Conference of Parties (COP18) of the United Nations Framework Convention on Climate Change (UNFCCC). We attended this UN climate conference in order to observe the impact of NGO's, to interpret the important outcomes of the COP, and to report back to students and chemists around the country, particularly the youth of the world who are not represented in these negotiations. A primary outcome of our participation is to make a positive difference for our future sustainability by uniting with other youth leaders and increasing climate literacy. Youth of the world, we need to let our voices be heard – join us in the conversation.

CHED 495

Influence of climate science research on policy negotiations at the 18th Conference of Parties

Nicole M. DeLuca,, Gregory P. Foy, Keith E. Peterman.Department of Chemistry, York College of Pennsylvania, York, Pennsylvania 17403, United States

In its endeavor to promote climate science literacy, ACS sponsored four students to attend the United Nations Framework Convention on Climate Change (UNFCCC) 18th Conference of Parties (COP18) in Doha, Qatar. We aspired to engage our peers and communities in climate change discussions through social media networking and local newspaper publications with a special emphasis on the communication of climate science research to the delegations of policy makers. As young people we represent one half of the world's population. While not officially represented in the international negotiations, the world's youth will face the consequences of climate change and manages a drastically different world if CO2 emissions do not peak in 2015. We have used this opportunity to set an example for educating ourselves and taking action in hopes of inspiring our elders, peers, and future generations about climate change and our role in it.

CHED 496

Introduction of HP-LC instrumentation to undergraduate students by quantitative analysis of caffeine and common analgesic drugs in locally available OTC formulations

Mary Alvarez,, Miriam Jaziri,, Peter Iles, Neil Bastian, Ron Valcarce, Luther Giddings, Yessenia Garcia, Kristi Nuckles, Sydney Richards.Department of Chemistry, Salt Lake Community College, Salt Lake City, Utah 84123, United States

Undergraduate community college students worked together to design, develop, implement, and test a procedure for the first semester organic chemistry laboratory class which implements valuable hands-on experience with LC-MS instrumentation. The relatively simple and cost effective quantitative analysis of nonprescription analgesic drugs was selected to meet the following criteria. The procedures developed fit within the standard 4 hour lab period and fit within the standard lab curriculum, including TLC analysis and use of serial dilution to create standards for quantitative analysis with linear regression. The experiment developed was also integrated appropriately with the curriculum of the first semester organic chemistry course, including the topics of functional group identification, polar-nonpolar interactions and MS fragmentation. Finally, the lab creates an awarenes for the worldwide problem of counterfeit drugs and was designed to relate to students interests; in particular, students who are on the pre-medical, pre-dental, and pre-pharmacy track.

CHED 497

Adaption of analytical procedures for GC-MS into undergraduate organic chemistry laboratories

Mary Alvarez,, Sydney Richards,, Peter Iles, Lacie Cates, Kristine Buttars, Spencer Bremer, Kylee Shumway, Mckinsie Oblad, Miriam Jaziri, Ron Valcarce, Neil Bastian, Luther Giddings.Department of Chemistry, Salt Lake Community College, Salt Lake City, Ut 84130, United States

Salt Lake Community College has aquired a GC-MS. The chemistry department is in the processs of incorporating this analytical technique into current organic chemistry labs. Undergraduate students are adapting a current essential oils extraction lab to include use of GC-MS for identification of the essential oil. The students are also creating a library of common household items that lab students can bring to class to run steam distillations and extractions on. The library will consist of GC-MS scans that students can compare their extractions against.

CHED 498

Fluoride by flow injection analysis: A new general chemistry experiment

Peter Iles, Brad Foster,, Zach Jones, Sarah Moore, Joseph Warren, Neil Bastian, Luther Giddings, Mary Alvarez, Ron Valcarce, Nathan Butler, Michael Tranter, Brian Louie, Shauna Mendes-Thorpe, Mahsa Adabkhah.Department of Chemistry, Salt Lake Community College, Salt Lake City, UT 84130, United States

An experiment for general chemistry lab to determine the amount of Fluoride in tap water was developed. The performance of Chemflow FIP-3 and FIP-4, and a Global FIA flow cells were evaluated with respect to sample through-put, precision and detection limit. The Chemflow FIP-3 and FIP-4 flow cells flow cell with an in-built reference system out-performed the Global flow cell in all parameters. Sample through-puts of 120 per hour were easily obtained. Though the Global flow cell had far slower sample throughput it could still be used in the time available for the lab class. The voltage measurements are performed with Microlab instruments and laptop computers. This experiment introduces students to the analytical applications of Voltaic cells as well as lab automation and micro and nanofluidic devices through Flow Injection Analysis while providing the students with an opportunity to make measurement that relate to their local community.

CHED 499

New general chemistry experiment: Analysis of trace metals by squarewave polarography in local rivers

Peter Iles, Chris Thurman,, Neil Bastian, Ron Valcarce, Mary Alvarez.Department of Chemistry, Salt Lake Community College, Salt Lake City, Ut 84130, United States

A new experiment for General Chemistry 2 lab where the students determine the amount of trace metals by squarewave polarography in local rivers is reported. The SLCC chemistry department has been investigating pollutants in the local rivers over the past 3 years and this has lead to the development of a new experiment for the general chemistry 2 lab where we are replacing some outdated electrochemical experiments with new instrumental methods. In this case the students are not only exposed the principles of electrolysis but also the quantitative aspects at trace level concentrations. Lead, cadmium and copper have been detected at ppb levels. The experiment allows the students also to make measurements on samples of local relevance.

CHED 500

Expansion of the Science Resource Center at Salt Lake Community College

Peter Iles, Sydney Richards,, Jory Lusk, Neil Bastian, Luther Giddings, Ryan Holcomb, Mary Alvarez.Department of Chemistry, Salt Lake Community College, Salt Lake City, Ut 84130, United States

The Science Resource Center at SLCC, originally established as a chemistry center, currently meets the needs of students, adjunct and full-time faculty for tutoring, computing, consultation, and group study in all the physical sciences. Data on the number of students and faculty served and the costs involved is reported. The developmental history of the center is reported here along with improvements in tutorial quality due to a second influx of one time funds. Examples of this are the expansion of the subjects covered, such as geosciences and engineering, as well as the SRC can now run summer PCAT review classes. The relationship between quality and the number of students assisted is presented. The history the various factors influencing the development, the funding and space issues and the blending with other resources of the division and school of Science Math and Engineering as well as outside sources.

CHED 501

Synthesis and LCMS analysis of the pharmaceutical Phenytoin demonstrating the pinacol rearrangement

Peter Iles, Subash Basnet,, Spencer Bremer, Jonathan Fisher, Nicholas Astorga, Mahsa Adabkhah, Amy H Ton, Ron Valcarce, Neil Bastian, Mary Alvarez, Luther Giddings.Department of Chemistry, Salt Lake Community College, Salt Lake City, UT 84130, United States

The purpose of this research project was to develop an undergraduate organic laboratory experiment to provide a demonstrable example of the Pinacol rearrangement. Phenytoin, an antiepileptic drug that was first synthesized in 1908 by the Biltz, is synthesized in this experiment is. This synthesis involves base catalyzed addition of urea to benzil followed by Pinacol rearrangement to form Phenytoin. This is an ideal synthesis for demonstrating the Pinacol rearrangement at the undergraduate level, since the starting materials are readily accessible, the synthesis can be achieved and product isolated within a three to four hour time frame and the product is easily characterized using FTIR and LCMS.

CHED 502

Rate a drug: A community health project

Peter Iles, Hazhar Yousif,, Sheeva Aboutaleb, Jonathan Fisher, Meghann Daw, Subash Basnet, Nicholas Astorga, Amy Ton, Kelly Ma, Michael Tranter, Macabe Coombs, Michael Smith, Darren Seegmiller, Darion Bevan, Ron Valcarce, Neil Bastian, Luther Giddings, Mary Alvarez.Department of Chemistry, Salt Lake Community College, Salt Lake City, UT 84130, United States

Understanding side effects, successful medications, and pathogenic effects is crucial to chemistry students going into a health related field. Working with the company, the Salt Lake Community rate a drug group (RAD) has endeavored to address the many what it takes to understand and educate the public on pharmaceuticals. Patient evaluations were carried out by patient perception surveys on the rate a drug website and addressed side effects and efficacy of medications and supplements. The work focuses specifically on a health condition where a blog was created and weekly updated to share with the public RAD's findings. Published information on side effects, dosage and details of specific drugs is also posted on The aim of the RAD's research is to raise awareness among students in our school, members of our community and, optimistically, the nation, about the personal responsibility to educate oneself about the medications being used.

CHED 503

Optimizing a nitration experiment

Tracey Engesser,, Robert Eliason, Noelle J. Beyer.Department of Science, Southwest Minnesota State University, Marshall, Minnesota 56258, United States

Electrophilic aromatic substitution reactions illustrated by nitration reactions are common in undergraduate organic laboratories, but no experiments utilize a stepwise addition of nitro groups to the aromatic system. The procedure of the well-known synthesis of 2-(2',4'-dinitrobenzyl)pyridine from 2-benzylpyridine gives dinitration exclusively. We are trying to enhance the pedagogical utility of this experiment. We have worked out a nitration procedure that leads to the formation of the mononitro product, 2-(4'-nitrobenzyl)pyridine, and we have successfully nitrated the mononitro product to 2-(2',4'-dinitrobenzyl)pyridine. We are currently working to optimize reaction conditions for use of this experiment in our organic chemistry course.

CHED 504

Effects of concept mapping on formal report quality in the general chemistry laboratory

Jerica L. Briggs,, Isaiah Cochran,, Megan Wojtowicz, Heidi J. Fletcher, Evonne Baldauff.Department of Chemistry and Forensic Science, Waynesburg University, Waynesburg, PA 15370, United States

A reoccurring issue in the general chemistry laboratory is that students fail to make connections between the data collected and the overall purpose for the experiment. This becomes apparent in the results and discussion section of the lab report and implies that the objectives of the experiment are not obvious or interpretable for the student. The use of concept mapping as a supplemental learning tool is a research-proven technique for improving student understanding of abstract concepts. The LabMap is a student-designed concept map intended to help students construct links between the purpose of the lab, the key data collected, and the results. All groups will perform the same experiment and be asked to write a formal report, with selected sections completing their concept map prior to writing the report. Final grades on all reports will be analyzed to create improvement curves. The LabMap documents will be collected, coded, and analyzed.

CHED 505

Development of an instructional laboratory experience utilizing 1H-NMR to determine fat characteristics from food samples

Amy C. Moore,, Aaron M. Hartel.Department of Chemistry, Winthrop University, Rock Hill, SC 29733, United States

Student engagement should be a priority in developing new laboratory experiences. We have developed a laboratory exercise in which students analyze packaged “convenience” foods (crackers, cookies, chips, candies) to determine several characteristics about the food's fat content. In this lab, students extract the fat from a sample of the food and gravimetrically determine the amount of fat per serving. The students acquire a 1H-NMR of the recovered fat and use the data to determine the levels of saturated, unsaturated, monounsaturated and polyunsaturated fats in the food. Students can then compare their results to the information provided on the food package label. This experiment engages students in the learning process by connecting with their prior knowledge and familiarity of the foods used. By performing the exercise, students learn several important concepts and techniques of organic chemistry such as extraction, filtration, structure-solubility relationships, NMR spectroscopy, and structural characteristics of fats.

CHED 506

Youth involvement at the 18th Conference of Parties and the need for climate science literacy

Parker D McCrary1,, Nicole M DeLuca2, Gregory P Foy2, Keith E Peterman2, Robin D Rogers1.  (1) Center for Green Manufacturing and Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487, United States  (2) Department of Physical Science, York College Pennsylvania, York, PA 17403, United States

Based on the increasing emphasis placed on climate science literacy by the American Chemical Society, a group of students were chosen to travel to Doha, Qatar to participate in the United Nations Framework Convention on Climate Change (UNFCCC) 18th Conference of Parties (COP18). Our primary purpose for attending the conference was to help engage the youth of our world and to promote youth involvement in the United States through social media networking. Although climate science literacy is increasing, more effort must be taken to advance the discourse in order to help promote sustainability and green chemistry. Our efforts are a small step towards climate science literacy, but our country must begin to take giant leaps. In this presentation, We discuss our experiences in attending COP 18 with a special emphasis on youth involvement and the need for climate science literacy.

CHED 507

Fabrication of a new metal organic framework for future gas storage applications

Anh T. Vu,, Anne M. Marti, Kenneth J. Balkus Jr..Department of Chemistry & The UTD NanoTech Institute, The University of Texas at Dallas, Richardson, TX 75080, United States

Metal organic frameworks (MOFs) are crystalline materials consisting of inorganic metal ions and organic linkers forming a variety of porous structures with high surface area and tunable properties. MOFs have been studied for applications such as gas separation and storage, as well as catalysis and chemical sensing. Our study involves the generation of a new MOF by extending the organic linker of an already known MOF, STU-1, which incorporates zinc and/or cobalt metal ions and linker molecules of 4-imidazolecarboxaldehyde. This involves the synthesis of a new crystalline organic linker by reacting two 4-imidazolecarboxaldehyde molecules with one ethylenediamine molecule, forming an imine bond, characterized by XRD, FT-IR, and SEM. The new organic linker has been utilized in the formation of the new MOF by solvothermally reacting it with zinc metal ions. We expect the new MOF to exhibit a high affinity for CO2 and become an interesting candidate for CO2 capture.

CHED 508

Small molecules, big ideas: Integrative chemistry and prison exchange

Zak A Johnson,, Samantha Glazier.Department of Chemistry, St. Lawrence University, Canton, New York 13617, United States

The goal of this project is to create a chemistry course for the Inside Out program at the Upstate Correctional Facility in Malone, NY that will develop students' reasoning along with central chemistry concepts of atomic structure, bonding, entropy, and enthalpy, to name a handful. Inside Out is a national prison exchange program that brings a college course to a prison, defined by collaboration between college students and incarcerated persons to learn a topic together. College students serve as a model for incarcerated persons in the development of study habits, creative thinking, logical reasoning and peer discussion with the intention of enriching personal academic experience. A complete syllabus outlining course requirements, evaluation criteria, and twelve new lesson plans will complete the first half of the project. The second half of the project will be the implementation of the course at Upstate Correctional Facility during the spring semester.

CHED 509

Evaluating effects of the Arlington undergraduate research-based achievement for STEM (AURAS) program on the performance of engineering students in chemistry courses

Emmanuel Varona,, Pricscila Martinez-Avila, Doug D. Carlton Jr., Abegayl Thomas, Kevin A. Schug.Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019, United States

Studies show that STEM students are poorly retained in their major. To address this problem, The University of Texas at Arlington developed a retention program to support STEM students. Arlington Undergraduate Research-based Achievement for STEM (AURAS) includes an Emerging Scholar Program (ESP) to support students in required chemistry courses. A learning outcomes-based assessment was developed to measure individual progress of students and to reinforce topics with poor performance. Quizzes and exams were aligned with learning outcomes and were used to assess individual mastery of course material. The assessment showed an upward trend in topics mastered and a high retention rate. Overall, there was a significant difference on test scores and course pass rates by students in ESP versus non- ESP students. Specifically, in fall 2011, 83% of ESP students earned a C or better in the course, as opposed to 57% of non- ESP students.

CHED 510

WikiHyperGlossary (WHG): New knowledge frameworks for historical documents and the role of Web APIs

Andrew P. Cornell1,, Mich A. Bau2,3, Daniel Berleant2, Robert E. Belford1.  (1) Department of Chemistry, University of Arkansas at Little Rock, Little Rock, AR 72204, United States  (2) Department of Information Science, University of Arkansas at Little Rock, Little Rock, AR 72204, United States  (3) Joint Bioinformatics Program, University of Arkansas for Medical Sciences, Little Rock, AR 72204, United States

One of the challenges early 21st century scientists and educators face is the implementation of digital ICTs (Information and Communication Technologies) in an information landscape paradigm based on Gutenberg era print-based communications. Through automated markup and Web APIs (Application Programming Interfaces) the WikiHyperGlossary (WHG) bridges these ICTs, directly connecting digitized printed documents to modern chemical information services and cheminformatic software agents. The result is the possibility of enhanced learning by connecting both current and historical print-based documents to social and semantic knowledge frameworks that provide new opportunities for knowledge discovery and verification. This poster will focus on the role of Web APIs and chemical identifiers in the WHG architecture. Specific examples will be provided along with a description of how the architecture enables the development of new features and supports extending this technology to other disciplines.

CHED 511

Video instructions for use of chemical instrumentation

Wojciech T Osowiecki,, Christine DiMeglio, Eric K Paulson.Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States

Contemporary multimedia technology has made it possible for almost anyone to produce and distribute video content, and students are increasingly beginning to expect tailored video content as a standard part of their learning process. In the Yale Chemical & Biophysical Instrumentation Center, we have made a series of targeted training videos covering the usage of specific analytical instruments and related software, including NMR, GC-MS, FTIR and MALDI-TOF MS. These videos, distributed via YouTube, complement written instructions and serve as an introduction for new users in the facility. They also lessen the work of faculty and staff by serving as a reference for the most frequently asked questions about the instruments. In this poster, we detail our experiences shooting videos in an often noisy open-access instrument center environment, and show how we have integrated video instruction into an undergraduate organic chemistry laboratory course.

CHED 512 General chemistry students' contribution and use patterns

Patrick McKeny,, Todd A Gatlin, Adrian Villalta-Cerdas, Santiago Sandi-Urena.Department of Chemistry, University of South Florida, Tampa, FL 33620, United States

Online rating websites such as (RMP) influence college professor and course selections. However, their use often sparks skepticism among instructors because of the self-selected nature of raters. Prior research on this topic in chemistry education concluded that RMP might be used as a valid source of supplemental information for evaluating instruction. The objectives of this study were to determine students' motives behind contributing to the site and to determine how students use the site to inform their decision making process. 500 General Chemistry students over the course of two years completed a 50-question survey addressing RMP use patterns. Findings suggest the majority of students use RMP and found it useful. Contributors' motives varied but were quite different from commonly held conceptions (e.g. They post to rant.). The contention is put forth that chemistry departments and professors may find a valuable supplemental source of information in RMP data.

CHED 513

Combined video and laboratory exercise for project-based isolation of medicinal compounds from osage orange

Margaret J. Risher,, William Whaley.Chemistry, Geosciences and Environmental Science, Tarleton State University, Stephenville, TX 76402, United States

Project-based learning experiences can be used to simulate a research problem in the Organic Chemistry teaching laboratory. A set of video recordings was developed to rapidly introduce the historical background for a project-based exercise that involves extraction and purification of two isoflavones from Osage orange. These isoflavones, osajin and pomiferin, differ by the presence of a single oxygen atom (in pomiferin); however, they have very different chemical and medicinal activities. Using a prepackaged Alumina-B cartridge, it is possible to rapidly purify these compounds in milligram quantities. These preparations are sufficient to allow analysis of these compounds by several instrumental methods. After students have had an opportunity to verify the structures of these purified compounds, they can experience a video that discusses potential uses of these compounds as medications or personal care products. The combination of video and laboratory exercise provides a time-efficient manner to deliver a project-based learning experience.

CHED 514

Simple lecture demonstrations of interfacial energy concepts using modern materials

Matthew A Luckey1,, Phillip W Alexander2, William A Alexander1.  (1) Department of Chemistry, The University of Memphis, Memphis, TN 38152, United States  (2) Department of Chemistry, Marshall University, Huntington, WV 25755, United States

Understanding intermolecular interactions is of paramount importance for students to develop a robust chemical intuition. Intermolecular interactions are inherently microscopic phenomena, which hardly lend themselves to effective and instructive classroom demonstrations. We use simple video equipment (i.e. “web cams”) to project the macroscopically-visible wetting behavior of droplet/surface systems, which results from specific interfacial intermolecular interactions. Using self-assembled monolayers as well-ordered model surfaces, we alter the interfacial chemical functionality, giving rise to variation in the contact angle of a sessile droplet. The different wetting properties of pine boards with 1) no treatment, 2) chemical pressure treatment, and 3) wood acetylation treatment are also compared. In addition to gaining an appreciation for how microscopic intermolecular interactions become important in the macroscopic world, using acetylated wood samples exposes students to a “new” chemical technology, and prompts discussion of “green chemistry” practices in wood preservation. Results from ongoing learning outcome assessments will be reported.

CHED 515

Spectroscopic and photochemical studies of sunscreen active ingredients: An undergraduate physical chemistry experiment

Megan S Claflin,, John D Thoemke.Department of Chemistry and Geology, Minnesota State University, Mankato, Mankato, MN 56001, United States

We have developed an undergraduate physical chemistry laboratory experiment examining the properties of three compounds that are active ingredients in common sunscreen products: avobenzone (1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)-1,3-propanedione), oxybenzone (2-hydroxy-4-methoxybenzophenone), octyl 4-methoxycinnamate (OMC) (2-ethylhexyl-4-methoxycinnamate). Aqueous solutions of the compounds are exposed to simulated sunlight in a merry-go-round photochemical reactor. Students work through a kinetic analysis of the direct photolysis of each compound using high performance liquid chromatography (HPLC) determination. Students also use rates of furfuryl alcohol consumption in the irradiated solutions to analyze the quantum yield of singlet oxygen production. Finally, absorbance and fluorescence spectra, along with each compound's molecular structure are evaluated. Students are then asked to correlate which compounds undergo direct photolysis, generate singlet oxygen, or resist photodegradation based on the compounds' molecular and spectroscopic characteristics.

CHED 516

Why do some students privilege chemistry knowledge while other students privilege consumer knowledge when confronting cost-benefits questions in chemistry?

Janessa` Dunn1,, Steven Culliper2, Shainaz M Landge1, Hannah Sevian2.  (1) Department of Chemistry, Georgia Southern University, Stateboro, Georgia 30458, United States  (2) Department of Chemistry, University of Massachusetts Boston, Boston, Massachusetts 02125, United States

Students apply both consumer and chemistry knowledge to solving problems in chemistry, particularly when those problems have relevance to their lives. In the context of studying a learning progression on chemical design across the timespan of middle school through graduation from university, undergraduate students' understanding of benefits, costs and risks in the design of chemical processes is being investigated. Preliminary data collected through surveys and interviews about a case study on refrigeration compounds revealed that, while students applied both consumer (common) knowledge and chemistry (school-based) knowledge to the case study, most undergraduate students taking general and organic chemistry at two culturally divergent universities privileged consumer knowledge over chemistry knowledge, while the opposite occurred with a small number of students. A second series of interviews intends to uncover relationships among demographic, interest, and ideology variables that may partially explain why one type of knowledge is privileged over the other.

CHED 517

Bridging the gap: A comparison of students' high school and general chemistry lab experiences

Megan Robb1,, Allison Kay1,, Thomas Bussey2, MaryKay Orgill2, Nathan Barrows1.  (1) Department of Chemistry, Grand Valley State University, Allendale, MI 49401, United States  (2) Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, NV 89154, United States

General chemistry is often an overwhelming experience for students. Although the laboratory component is often viewed by instructors as another way to increase student understanding of concepts, the lab experience can be quite frustrating and add to students' confusion. Whereas instructors might attribute difficulties in lab to negative attitudes, poor preparation for lab, or inattention to lab procedures, they often forget that their students bring a wide variety of high school lab experiences to the college classroom. Difficulties in lab may exist due to the disparity between the lab skills taught at the high-school level and the performance expectations of college lab instructors, but relatively few research studies have directly examined this factor via student interviews. This qualitative study investigated students' lab experiences at the high school and college levels via focus group and individual interviews. The recordings were transcribed and analyzed using methods informed by grounded theory.

CHED 518

Fun and frustration: Students' perspectives of college-level laboratories

Allison Kay1,, Megan Robb1,, Thomas Bussey2, MaryKay Orgill2, Nathan Barrows1.  (1) Department of Chemistry, Grand Valley State University, Allendale, MI 49401, United States  (2) Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, NV 89154, United States

For the past several decades, the lab curriculum of college-level chemistry courses has gradually shifted to incorporate more inquiry-based investigations. While some students and instructors respond favorably to these changes, others are more resistant. Although instructors and students might be expected to have very different perspectives of lab activities, students are by no means a homogeneous group in this regard. This study investigated the experiences, preferences, and frustrations of 24 students regarding their college-level chemistry labs. Preliminary data analysis indicates that students attached strong negative and positive feelings to specific lab activities, the organization of the lab environment, and the extramural requirements associated with a chemistry laboratory.

CHED 519

Spelling words using chemical element symbols

Nizhonabah Williams,, Sunny McCabe,, Josie Martinez,, Ashley Shondee,, Kassie Shondee,, Mariah Yazzie,, David J. Duncan.DEPARTMENT OF CHEMISTRY, GANADO UNIFIED SCHOOL DISTRICT, Ganado, AZ 86505, United States

One of the struggles of a first year Chemistry student is to be able to learn chemical element names, and chemical element symbols. Each student is essentially a Science Language Learner (SLL). This lesson incorporates using chemical symbols to spell ordinary words. It helps familiarize the students with the spelling of the elements and their pronunciations. It causes students to become familiar with element locations on the periodic table. In addition, they are able to translate from element to symbol and from symbol to element name. Some students really enjoy this lesson. From 72 student's submissions we were able to compile a list of over 1400 unique words using over 109 of 118 different symbols.

CHED 520

Live action chemistry displays and related material science

Tate J Campbell,, Thomas W. Killingsworth.Department of Chemistry & Biochemistry, California State University, Chico, Chico, CA 95926, United States

Development of live-action chemistry demonstrations for display cases and museums will be presented. We have been developing self-contained chemical reactions. These self-contained set ups are designed last for weeks. They are also chosen to develop interest and keep viewers coming back for more time-after-time. Systems that have been developed, are being developed and planned to be developed will be presented. Correlation of the systems with the NRS standards for informal science education will also be presented. The focus of our systems is on small, airtight apparatus' which contain two separate aqueous solutions. These systems can be used in order to study evaporation and diffusivity of gaseous species in the atmosphere, typically strongly ammoniacal solutions in conjunction with ionic cuprous solutions have been used in the past.

CHED 521

Synthesizing cadmium selenide quantum dots for an educational demonstration on fluorescence

Jessica Barilone,, Patrick Wallace, Alex Blanchard, Henry Brown, Peter Woodruff.Department of Chemistry, University of Southern Maine, Portland, Maine 04104, United States

The USM Chemistry Club works to develop new and interesting ways to educate students of all ages about a variety of chemical principles. Each year we work to incorporate new demonstrations that highlight a different principle. The University of Southern Maine Chemistry Club synthesized quantum dots as a means to demonstrate the various fluorescence capabilities of molecules, and the different energies associated with different wavelengths of light. Quantum dots are a type of nanoscale particle whose electronic energy levels are dependent on their individual size, quantum dots of various diameters emit photons of different energy levels due to quantum confinement effects. The unique properties of quantum dots have made them useful in applications such as optoelectronics, wavelength tunable lasers, and bioanalytical methods. Quantum dots can be used as a safe, interactive way for children to observe the effects of electronic excitation, and photon emission.

CHED 522

University of Southern Maine department of chemistry encourages local teens to embrace STEM fields through hands-on laboratory experiments

Alex Blanchard,, David Finocchietti, Courtney Pizzo, Peter Woodruff.Department of Chemistry, University of Southern Maine, Portland, Maine 04104, United States

The University of Southern Maine Department of Chemistry and Chemistry Club work in concert to connect with students from local high schools. This year a collaborative project was developed to encourage students to enroll in STEM (science, technology, engineering, mathematics) programs. Members of the USM Chemistry club worked alongside chemistry faculty to teach basic laboratory techniques to local high school students. Over 100 students from Casco Bay High School's sophomore class were invited to work in laboratories at the University of Southern Maine. The students worked in the analytical, organic, and biochemistry laboratories and learned about 1) organic extractions via column chromatography, 2) thin layer chromatography and 3) fluorometry. The goal of this project was to expose students to basic laboratory techniques and instrumentation in hopes that it will encourage them to pursue a career in the STEM fields.

CHED 523

Affinity capillary electrophoresis for the study of glycosaminoglycan-protein interactions

McKenna Feltes,, Brittany Sanders,, Albert Korir.Department of Chemistry, Drury University, Springfield, Missouri 65802, United States

Glycosaminoglycans (GAGs), such as heparin and heparan sulfates, are known to influence in-vivo activities of a wide range of proteins. GAGs consist of repeat disaccharide units that differ in basic monosaccharide sequence, substitution pattern, and stereochemistry of the glycosidic linkages. The structural complexity of GAG chains present considerable challenges in studying their molecular interactions with proteins. We present an affinity capillary electrophoresis (ACE) method to study GAG-protein interactions. ACE is well suited for highly anionic analytes, such as heparin-derived oligosaccharides, for which large differences in electrophoretic mobility can be observed between the complex and the free target protein. Binding parameters can be obtained reproducibly with minimal sample consumption. Results obtained will be validated using computational approaches and nuclear magnetic resonance (NMR) spectroscopy. Elucidation of GAG-protein interactions can provide critical insight into mechanisms underlying important biological processes.

CHED 524

Solvent free stereoselective reduction of carbonyl groups

Emmanuel Lopez-Nogueras1,, David Sanabria2, Ingrid Montes-Gonzalez1, Sara M Delgado-Rivera1.  (1) Department of Chemistry, University of Puerto Rico Rio Piedras Campus, San Juan, Puerto Rico 00931, Puerto Rico  (2) Department of Chemistry, Interamerican University of Puerto Rico Metro Campus, San Juan, Puerto Rico 00926, Puerto Rico

Stereoselective reductions are very important in organic synthesis. Reduction reactions have been thoroughly discussed in undergraduate organic chemistry laboratory textbooks, however most procedures highlight the reaction with little or no emphasis on its stereoselectivity. This poster presents an experiment using the guided-inquiry approach for a systematic study on the stereoselective reduction of cyclohexanone derivatives applying green chemistry principles. This approach consists mainly, but not exclusively, of a solvent free media. Parameters such as stoichiometry, stirring time, and temperature were studied. Spectroscopic techniques were implemented to characterize and determine the stereoselectivity of the products. It is expected that after the laboratory, the student will have a more in-depth knowledge of NMR spectroscopy and understand the full advantages of this technique. This will help them to integrate learned fundamental concepts and encouraging them to explore a research-type experience in the solution of problems.

CHED 525

Electrophoretic deposition of Co nanoparticles for Co3O4 films

Don-Hyung Ha2, Richard Robinson2, Diana M Gooding1,  (1) Department of Physics, Transylvania University, Lexington, Kentucky 40508, United States  (2) Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, United States

Co3O4 nanoparticles are an attractive material for Li-ion battery anodes, because they have a volumetric and gravimetric capacity 2.5 times greater than that of graphite. These anodes can be prepared through calcination of electrophoretically deposited films of Co nanoparticles. While this method produces battery anodes with high gravimetric (>830 mAh/g) and volumetric (>2100 mAh/cm3) capacities, the deposited film's thickness and density are crucial to the battery's capacity and longevity. This work demonstrates control over the thickness and density of Co3O4 NP films through the variation of electrophoretic deposition (EPD) parameters. Starting with Co nanoparticles, we altered the solution concentration and applied voltage across an EPD cell. Generally, the resulting films' density increases with increasing voltage, and decreases with increasing concentration. Because these trends hold for films in the Co3O4 phase, we demonstrate the ability to tune the thickness and density of Co3O4 films starting simply with EPD parameters.

CHED 526

Bridging knowledge gaps in chemical concepts

Connie Gabel, Cristina Winchester,, Jeremy O'Brien, of Chemistry, Metropolitan State University of Denver, Denver, Colorado 80217, United States

General chemistry knowledge is important for chemistry and biology students. By improving chemistry knowledge, biology students should have a more conceptual understanding of these topics. Students are expected to have prior knowledge of algebraic methods when they enter general chemistry. In assessing their ability to apply these skills to chemistry problems, their understanding of these concepts is determined. Supplemental Instruction (SI) provides an opportunity for students, outside of traditional lecture, to apply chemical knowledge to problems and discussion. The SI Peer Leader serves as the expert in constructing chemical knowledge. Students are often unable to identify gaps in their knowledge. By asking appropriate questions, the expert is able to identify knowledge gaps and help students make connections between chemical concepts. In this way, students are able to achieve greater depth of knowledge. The purpose of this research was to assess if there is a benefit to students participating in SI.

CHED 527

Green organic chemistry labs at a community college

Pei Shan Chen,, Homar Barcena.Physical Sciences, Kingsborough Community College, Brooklyn, NY 11235, United States

Green organic chemistry labs were tested for use in a community college classroom setting. Experiments were adapted for teaching colleges that have few resources and are not equipped with a fume cupboard for each student to use. Standard laboratory glassware were used, as well as characterization methods. Multiple-step reactions were also developed sequentially to follow the pace of the lecture.

CHED 528

Design and implementation of high school chemistry labs utilizing remote scanning electron microscopy

Joseph H. Gault,, Emily L Janicki, Kimberly A Rosmus, Nolan R Larry, Jennifer A Aitken.Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15219, United States

Scanning electron microscopy uses electrons to produce magnified images of samples with a resolution on the order of several nanometers and large depth of field. The SEM at Duquesne University was set up for remote access through a standard Internet connection. To begin with, two chemistry labs were designed to implement the use of the scanning electron microscope (SEM) in a high school classroom setting. An introductory laboratory using a copper penny serves to introduce students to the microscope and basic techniques of microscopy. A more advanced laboratory on imaging aluminum hydroxide crystals obtained from the decomposition of a standard aluminum can was also designed. For each lab, a presentation tutorial, student and teacher handouts, video tutorials, and pictures of the samples were created. Additionally, the concepts of the labs include Pennsylvania State Standards, which are highlighted in the respective laboratory manuals that were prepared in this work.

CHED 529

Synthesis of a fluorescent conjugated polymer in the undergraduate teaching laboratory

Teresa Mako,, Mindy Levine.Department of Chemistry, University of Rhode Island, Kingston, RI 02881, United States

Reported herein is the synthesis of a fluorescent conjugated polymer in an undergraduate teaching laboratory. While fluorescent polymers have tremendous utility in research laboratories and in industry, there are only a handful of examples of polymer synthesis in the undergraduate laboratory setting. Previous syntheses of MEH-PPV (poly[2-methoxy-5-(2'-ethylhexyloxy)-p-phenylene vinylene]) were examined and modified into a procedure amenable for an undergraduate teaching laboratory. This modified synthesis was performed in a three-hour laboratory period without requiring a glovebox or excessive inert atmosphere conditions. Once synthesized, the polymer was characterized by absorbance and fluorescence spectroscopy, as well as NMR spectroscopy. The polymer was also used for the synthesis of nanoparticles and thin films. In summary, 13/14 students in the laboratory were able to successfully synthesize and characterize the polymer, MEH-PPV, using our newly developed procedure.

CHED 530

Novel approach to increase student satisfaction and performance in organic chemistry

Jacob R Acharte,, Holly L Sebahar,, University of Utah, Salt Lake City, Utah 84115, United States

In an Organic Chemistry classroom of 200+ students it can be both overwhelming and difficult for the professor and students to build a relationship. This lack of connection can have negative affects on the student's overall grade, college experience, and future career. Method used: TA's would meet with students once a week to go over the previous discussion worksheet. TA's got to get to know their students and were able to identify their needs. After each session the TA's reported back to the professor clarifying the student struggles. Students with lower grades were selected to comprise the majority of the group, but it was critical that a few students within the group have high grades. The students in the program reported back with 100% satisfaction. Data also revealed that students in the program scored 10.2% points higher than the class average on each exam and 14.4% higher on the final.

CHED 531

Acquire the practical skills and knowledge needed for the chemical industry with an associate's in industrial chemistry technology alongside a bachelor's degree

Kimberly R Johnson1,, Joseph C Christy-Saviano1, B Q Wierckz1, Tyler Weatherwax1, Pasquale R Di Raddo.  (1) Department of Physical Sciences, Ferris State University, Big Rapids, MI 49307, United States

With an associate's degree in Industrial Chemistry Technology that easily coincides with any science major, a new graduate has more practical laboratory skills and knowledge of chemical safety than the average graduate with only a bachelor's. Employers and graduate recruiters see these students as more resourceful and qualified because of the extra preparation that this program has to offer. The program focuses on the main components of working in industry stressing laboratory calculations, safety hazards of common chemicals and keeping an excellent laboratory notebook. The Chemical Manufacturing-Analysis class provides the greatest preparation for an upcoming graduate by replicating an actual work day in industry. It focuses on the preparation and analysis of various materials by using FT-IR, NMR, Mass Spectrometer and Gas Chromatography. Students also partake in an ongoing research project by varying reaction conditions to develop a more efficient reaction pathway of the production of a dye called dibenzanthrone.

CHED 532

Using computational chemistry in biochemistry: Why did nature not select silicon for biological molecules?

Blakely Sanders1,, Haley Norris1, Chelsea Swords2, Maureen K. Murphy1,  (1) Department of Chemistry and Biochemistry, Huntingdon College, Montgomery, AL 36106, United States  (2) Department of Biology, Huntingdon College, Montgomery, AL 36106, United States

We have used computational chemistry (HyperChem 8.0) to compare minimized energies, lowest energy conformations, bond angles, and bond lengths in a series of biologically important molecules including the small peptide hormone oxytocin, glucose, protoporphyrin IX dimethylester (PPIXDME), tetraphenylporphyrin, ATP, cocaine, NADH, propofol, and limonene. A comparison of the energies, bond measurements, and lowest energy conformations of the carbon-based molecules with their silicon analogs showed unsual structures and energies of the silicon analogs.

CHED 533

Conformational influence of fluorine substitution on peptides derived from β-amino acids

Alec D. Emerling1,, Gary S. Kedziora2, Joseph J. Urban1.  (1) Chemistry Department, U. S. Naval Academy, Annapolis, MD 21402, United States  (2) High Performance Technologies, Wright Patterson AFB, OH 45433, United States

Fluorine's unique ability to participate in a number of subtle stereoelectronic effects has prompted its use as a tool to control the conformation of peptide analogs. The conformational energies of model β-amino acid peptides, and their fluorinated analogs, have been explored using a combination of correlated wave function and density functional theory calculations. Results from a variety of methods including ωB97X-D/cc-pVTZ, b3lyp/6-311++G**, and M062X/cc-pVTZ are compared to benchmark results from coupled-cluster calculations (CCSD(T)) employing complete basis set (CBS) extrapolation methods. The impact of aqueous solvation on the conformational profiles is also examined via a continuum solvation model. These results contribute to a better understanding of the impact of selective fluorination on the conformational preferences of model peptide mimics.

CHED 534

Conformational preferences for C-F bonds adjacent to carbonyls

Eric W. Emerling1,, Gary S. Kedziora2, Joseph J. Urban1.  (1) Chemistry Department, U. S. Naval Academy, Annapolis, MD 21402, United States  (2) High Performance Technologies, Wright Patterson AFB, OH 45433, United States

In compounds containing a fluorine adjacent to a carbonyl, a preference for the conformation with the C-F bond anti to the C=O bond has been noted. This effect is particularly pronounced in α-fluoroamides, but has been described in other functional groups as well. The goals of this work are to employ computational chemistry methods to explore the generality of this effect by examining a variety of functional groups, to determine if trifluoromethyl groups participate in a similar effect, and to determine the impact of solvent medium on the effect. Rotational profiles about the C-C bond in compounds containing X-C-C=O, where X = F, CF3, have been generated at the ωB97X-D/cc-pVTZ level of theory. Examples where the carbonyl is part of an aldehyde, ketone, amide, acid, or ester have been considered. The minima found in the gaseous phase and in an aqueous environment as described by a continuum solvation model are compared. The conformational preferences are analyzed in terms of a number of underlying effects including sterics, electrostatics, and orbital considerations.

CHED 535

Computational analysis of thiolated gold nanoparticles

Morgan R Olsen,, Kevin Range.Department of Chemistry, Lock Haven University, Lock Haven, PA 17745, United States

Gold nanoparticles are being studied extensively for their optical, electronic, and molecular recognition properties. Thiolated gold nanoparticles behave differently than traditional bulk materials. The goal is to use computational chemistry to see the effect of putting different terminated ends on thiolated gold nanoparticles.

CHED 536

Effect of dielectric constant on bond critical point descriptors in model nucleotide dimers

Christian M Posea,, Harry L Price.Department of Chemistry, Stetson University, DeLand, Florida 32723, United States

Hydrogen bonding plays an important role in modulating the stability of molecular complexes. The goal of this investigation is to examine the effect that dielectric constant has on H-bonds present in adenine-thymine and adenine-uracil dimers. Specifically, we are interested in determining whether H-bonds in these dimers are equivalent, and how each responds to changes in dielectric constant. To begin to address these questions the electron density and laplacian of the electron density at the bond critical point (BCP) were calculated for geometry-optimized complexes in six media having dielectric constants ranging from 0 to 78.36 Debye using the Self-Consistent Isodensity Surface Polarizable Continuum model. Understanding the differential response of these descriptors to changes in dielectric constant may contribute to a better understanding of the importance H-bonding has as a modulator of these dynamic associations.

CHED 537

Computational study of selenoproteins involved in the activation of thyroxine.

Zachary B. Gottleib,, William M. Davis.Department of Chemistry, Texas Lutheran University, Seguin, Texas 78155, United States

The understanding of selenoproteins, such as Iodothyronine deiodinase, plays an important role in the activation and inactivation of thyroxine. While this class of proteins does contain selenocysteine, a unique feature is the use of a cysteine to cooperatively bond to selenium while halogen bonding to iodine so that thyroxine can be activated. This combination occurring in the human body is strange because as calculated by Debasish Manna the use of two selenium atoms is the most energy efficient way to remove iodine from thyroxine. This study takes a computational approach using Gaussian 03 and Spartan to look at the energies of the model complexes to see if this trend continues with the addition of tellurium to the model complexes, as well as to see if there are significant energy differences in the complexes depending on which chalcogen is participating in the halogen bond to iodine. Though the limitations of basis sets in the Gaussian software and only preliminary analysis through Spartan have revealed little to the bonding and energy trends of the model complexes.

CHED 538

Correlation between band gap and electronegativity of substituted atoms in the TiO2 crystalline structure

Andrew J Glaid,, Matthew N Srnec, Jennifer A Aitken, Jeffry D Madura.Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15219, United States

The electronic structure of TiO2 has been extensively studied through a variety of experimental and computational methods. Its properties range from thin film photovoltaic cells to optics. TiO2 provides an excellent model to study computationally due to the wealth of experimental data and its inexpensive computational cost. Our hypothesis is that the electronegativity of a substituent changes the band gap of crystalline TiO2. Atoms of different electronegativities were selected for substitution into the three polymorphic forms of TiO2, which are rutile, anatase, and brookite. Our computational approach utilizes the linearized augmented plane wave approach of density functional theory in the WIEN2k computational software, and includes the incorporation of the modified Becke-Johnson potential, to determine the band gap and density of states for each case. Initial results showed that there was a positive correlation between the electronegativity of the substituent and the structure's band gap.

CHED 539

Micellization of small biomolecules: Molecular dynamics simulation

Daniel Daigle,, Caleb Delaune,, Hye-Young Kim.Department of Chemistry and Physics, Southeastern Louisiana University, Hammond, LA 70402, United States

We have performed molecular dynamics simulations using GROMACS to study the micellization of a newly synthesized amphiphilic antioxidant molecule, Vecar [1]. The chemical structure of the molecule is composed of a truncated vitamin E and a slightly modified Carnosine which are, respectively, linked to the opposite ends of a simple carbon chain of varying numbers of carbon atoms (0 to 18). The force field of this new molecule is generated from the Automatic Topology Builder. We will report the progress and results of our computer simulation study. This research is supported by Louisiana BOR grant (LEQSF(2012-15)-RD-A-19) and by the Louisiana Optical Network Institute (LONI).

[1] C. Astete, D. S. Meador, D. Spivak, and C. Sabliov, Synthetic Communications, DOI: 10.1080/00397911.2011.632829 (published online in 20 April 2012).

CHED 540

PM3 and PM6 calculations on organometallic dehydrogenation catalysts

Alison Konieczki,, Lauren Martin, Sarah Schwartz, Jeff Seyler.Chemistry, Univ of Southern Indiana, Evansville, IN 47712, United States

Semi-empirical methods have been used to investigate the catalytic mechanisms for Iridium
pincer dehydrogenation catalysts. The intent of the current study is to compare the results of past PM3 calculations (Spartan '10, Wavefunction, Inc.) with results using the newer PM6 level of theory. For this report, the pincer ligand included the isopropyl-substituted PCP systems, and cyclooctane was used as the organic substrate in the formation of H2 and cyclooctene. Geometry optimizations with PM6 have proven to be problematic with these organometallic systems. In cases where PM6 optimization failed to generate appropriate geometries, single point calculations were performed using the PM3 optimized geometries. Transition states for oxidative addition of cyclooctane and beta elimination in cyclooctyl complexes were obtained with both PM3 and PM6. This presentation will provide some mechanistic details in the catalytic cycle following these semi-empirical calculations with the Iridium pincer complexes.

CHED 541

Computer simulations of anion adsorption to metal organic frameworks

Jennifer N. Loftin,, Jordan M. Lovejoy,, Jeffrey N. Woodford.Department of Chemistry, Missouri Western State University, Saint Joseph, Missouri 64507, United States

A new class of materials, metal organic frameworks (MOFs), have potential applications in many areas, including catalysis, gas storage, drug delivery, biomedical imaging, and chemical separations. MOFs can be designed for specific applications by joining certain metals with organic linkers. We are investigating the adsorption of selected anions, such as nitrate, perchlorate and chloride, with cationic MOFs. Specifically, we will study Cu(II) and Al(III) MOFs because they have been shown to exhibit selective anion exchange and have stability in aqueous solution. Our investigation is composed of two parts. The first part is comprised of ab initio calculations to find interaction energies between anions and MOF structural binding units (SBUs). The second part involves performing molecular dynamics simulations to compare the equilibrium distribution of anions in the MOF pores compared to bulk solvent. Results will be presented based on these simulations.

CHED 542

Catalytic effect of Cu modified FAU zeolite on nitrous oxide

A. William Barber,, Joo Young Yim,, Heriberto Hernandez.Department of Chemistry, Grinnell College, Grinnell, IA 50112, United States

We investigated the absorption of N2O on a Cu-FAU zeolite using density functional theory. Computations were performed with a two layer ONIOM method. For the high layer, we used B3LYP/6-31+G(d) level of theory, and for the lower layer we used Molecular Mechanics (MM) employing the Universal Force Field (UFF). The results showed that a covalent bond formed between O and Cu upon absorption, with binding energy of 154.9 kJ∙mol-1. Furthermore, the N-O bond elongated by 15.5% of its original bond length suggesting that N2O dissociates to produce N2(g) upon interaction with a Cu-FAU zeolite.

CHED 543

Investigating the sticking of hydrogen on graphene

Andrew D. Geragotelis1,, Dennis P. Clougherty2.  (1) Department of Chemistry, Siena College, Loudonville, New York 12211, United States  (2) Department of Physics, University of Vermont, Burlington, VT 05405, United States

Theoretical physics at low temperatures allows us to learn about the fundamental properties of materials at nanoscale dimensions. This work focuses on the interaction between a hydrogen atom and a graphene sheet. We calculated the physisorption rate of atomic hydrogen at normal incidence onto graphene using Fermi's Golden Rule. The calculation shows a bound state energy of -24.9 meV. Over the range of incident energies considered (1-10 meV), we find that the sticking probability decreases as the incident energy of the hydrogen atom is increased. The work was performed as part of the REU on Complex Materials at the University of Vermont under the supervision of Dennis Clougherty.

CHED 544

Electronic structure modeling to explore the existence of pnictide analogs to HCN species

Cameron P Glagola,, Deborah Sunderland, Robbie J Iuliucci.Department of Chemistry, Washington and Jefferson College, Washington, PA 15301, United States

Pnictides are chemical compounds that contain Group 15 elements. Currently, synthetic pathways are known for the compounds HCN and HCP; however, the heavier Group 15 analogs (namely HCAs, HCSb, and HCBi) have yet to be synthesized. The theoretical existence of these molecules was explored via a Gaussian quantum chemistry composite method as well as frequency calculations in order to predict their thermodynamic properties, their molecular orbitals, and to probe bond length trends.

CHED 545

Cycloadditon reactions of sulfinyl carbenes with alkenes and alkynes

Danielle J Turnquest2,, Fillmore Freeman1.  (1) Department of Chemistry, University of California, Irvine, Irvine, CA 92651, United States  (2) Department of Chemistry, Florida Memorial University, Miami Gardens, FL 33054, United States

Moeller-Plesset perturbation theory (MP2) and the hybrid density functionals B3LYP, B3PW91, and PBE1PBE with the 6-311+G(d,p) basis set and also CCSD(T) and QCISD(T) with the cc-pVTZ and cc-pVQZ basis sets have been used to study the structures of sulfinyl carbenes and the mechanisms of their cycloaddition reactions to alkenes to form cyclopropanes and to alkynes to form cyclopropenes. Electron donation of the lone pair electrons on sulfur into the vacant p orbital of the singlet carbene serves to stabilize it. In addition to the transition states, the dipole moments, atomic charges, singlet-triplet gaps, and vibrational frequencies of the sulfinyl carbenes were also studied.

CHED 546

Role of tyrosine O-sulfation in the CXCR4-SDF-1 chemokine receptor complex

Sara Snow,, Chaya Rapp.Department of Chemistry and Biochemistry, Stern College for Women, New York, New York 10016, United States

The CXCR4-SDF-1 chemokine receptor complex is involved in both normal and pathological functions in the body, including cancer metastasis. The CXCR4 receptor is post-translationally modified by tyrosine sulfation at three sites on its N terminus, and this modification is required for binding to the SDF-1 chemokine. To study the role of tyrosine sulfation in the structure and dynamics of the CXCR4-SDF-1 complex, we conducted molecular dynamics simulations on experimentally determined complexes of CXCR4-SDF-1 that were unsulfated, partially sulfated, and fully sulfated. A comparison of hydrogen bonding and torsional motions in the simulation trajectories shows that sulfation plays a role in dimer stabilization, and that each additional sulfation site adds to the stability of the dimeric complex. It is hoped that this work will contribute to therapeutic efforts which target sulfated systems.

CHED 547

Configurational dependence of temperature in the potential energy landscape ensemble

Matthew Fritz,, Jeb Kegerreis.Department of Chemistry, Shippensburg University, Shippensburg, PA 17257, United States

Low cost computational methods were employed to evaluate the configurational dependence of temperature in the potential energy landscape ensemble for glassy atomic systems with o-terphenyl (OTP) as the model. In addition to the global minimal configuration, local minima were explored and each produced a significantly different temperature and landscape energy implying another ensemble may be more descriptive of glassy atomic systems.

CHED 548

Comparative analysis of symmetry-adapted perturbation theory

Alden Grant Ryno,, Trent Parker, C. David Sherrill.Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States

Noncovalent interaction are prevalent in chemical systems including protein folding, organic crystals, nucleic acids, and the formation of materials. These interactions are quantitatively and qualitatively studied by employing computationally expensive wavefunction-based quantum chemical methods. One method in particular, Symmetry-Adapted Perturbation Theory(SAPT), allows the interaction energy to be computed along with the electrostatic, exchange, induction, and dispersion energies. Here, various levels of SAPT were tested using the S22, HSG, HBC6, and NBC10 databases in order to find a lower level of SAPT that produced accurate results at a low computational cost. Four levels of SAPT and 10 Basis sets were used in this study with the best overall test pairs being SAPT2+/aDZ and SAPT2+(3)/aDZ. However, since both SAPT2+ and SAPT2+(3) are higher levels of theory, they are quite costly. For both high accuracy and low computational expense, the SAPT0/jaDZ test pair is an exceptional match. SAPT0/jaDZ produced a mean unsigned error of less than 0.5 kcal mol-1 at roughly one-half and one-quarter the computational times for SAPT2+/aDZ and SAPT2+(3)/aDZ, respectively.

CHED 549

Beyond octanitrocubane: A theoretical C-8 octanitro compound having an oxygen balance of zero

Jesse L Hansen,, John A Bumpus.Department of Chemistry and Biochemistry, University of Northern Iowa, Cedar Falls, IA 50613, United States

Octanitrocubane is a relatively new high energy density material (HEDM) that has potential use as a high explosive. However, its large scale use is prevented because of its high production cost. Our laboratory is interested in the identification and computational characterization of other C-8 octanitro compounds as targets for possible synthesis and development as high explosives. We characterized octanitrotetracyclo[,5.03,8]oct-1-ene. This compound is unique with regard to other theoretical C8 octanitro compounds that we have studied in that, like octanitrocubane, it has an oxygen balance of zero. In addition to oxygen balance, several other parameters (power index, explosive velocity and detonation pressure) indicate that this compound would be at least as effective as octanitrocubane as a high explosive.

CHED 550

Effects of tyrosine O-sulfation on binding affinity in CXCR4-SDF-1 complexes

Talya S. Laufer,, Chaya Rapp.Department of Chemistry and Biochemistry, Stern College for Women, Yeshiva University, New York, New York 10016, United States

Certain secreted proteins in biological systems undergo the post-translational modification of tyrosine O-sulfation, wherein a number of Tyr residues are sulfated at their hydroxyl groups, forming what is referred to as a Tys residue. The current study investigates the effects of tyrosine sulfation on the strength of protein-protein interactions, as attested to by the binding energies of the CXCR4 chemokine receptor in complex with its SDF-1 chemokine ligand. The Protein Databank includes three distinct dimeric CXCR4-SDF-1 structural complexes: 2k04, 2k03, and 2k05. 2k04 is the un-sulfated protein complex; 2k03 is sulfated once in each monomer on residue Tyr21; 2k05 is sulfated on Tyr7, Tyr12, and Tyr21 in both monomers. A program called APBS was used to determine the binding energies of the dimeric complexes and of their corresponding monomers. APBS utilizes the Poisson-Boltzman equation to incorporate solvation free energies in the calculation of binding energies. Results of APBS calculations showed that as the degree of tyrosine sulfation increases, the binding energies of the complexes become more favorable, with the most significant decrease in binding energy occurring between the partially sulfated (2k03) and fully sulfated (2k05) dimeric complexes. The increased stabilization of the dimeric complexes as compared to the monomeric complexes is a result of interactions occurring across the dimer interface, i.e. between each sulfated CXCR4 chain and both SDF-1 ligands. This indicates that sulfation serves both to enhance binding affinity between CXCR4 and SDF-1, and to stabilize the dimeric state of the CXCR4-SDF-1 complex.

CHED 551

Modeling and understanding of solvent effects on 13C NMR spectroscopy

John P Siller,, James B Foresman.Department of Physical Sciences, York College of Pennsylvania, York, Pennsylvania 17403, United States

Differences arise in Nuclear Magnetic Resonance (NMR) spectroscopy when analyzing the same solute with different solvents. These solvent effects shift the NMR spectra in different ways. Electronic structure codes such as Gaussian 09 can represent solvent effects using a continuum model and also by including specific solvent molecules in the calculation of 13C chemical shifts, but current methods are limited and do not precisely match experimental data. The objective of this study is to close the gap between experimental and calculated spectral data by determining the factors that affect this data and better represent these factors with computational techniques. This study attempts to discern what amount of error is due to neglect of solvent and what error is due to the theoretical model.

CHED 552

Evaluating HADDOCK's ability to use experimental data in docking a protein-ligand complex

Tracy L Wormwood,, Jeffrey S Grinstead.Department of Chemistry, University of Puget Sound, Tacoma, Washington 98416, United States

With the advent of docking systems for modeling the interactions of proteins, HADDOCK is a docking tool powerful in its abilities to use experimental data and allow for protein flexibility in docking of proteins with other biomolecules including ligands. The present research evaluates the influence of real experimental data on the docking of a protein-ligand interaction between protein tyrosine phosphatase 1b (PTP1b) and one of its chemical inhibitors: 5-iodo-2-(oxalylamino) benzoic acid. Either NMR chemical shift perturbation data, or known binding-site residues were used to drive consequent docking. The effect of different starting protein conformations was measured. Success of each docking was evaluated by comparing the HADDOCK score to ligand-RMSD and fraction of native protein-ligand contacts.

CHED 553

Benchmarking screened hybrid and "Rung 3.5" density functionals for transition metal thermochemistry

Katelyn E. Poole1,2,, Marie L. Laury2, Angela K. Wilson2, Benjamin G. Janesko1.  (1) Department of Chemistry, Texas Christian University, Fort Worth, TX 76129, United States  (2) Department of Chemistry, University of North Texas, Denton, TX 76203, United States

Accurate, computationally tractable thermochemical predictions for transition metal (TM) complexes remain an important challenge in electronic structure theory. Density functional theory (DFT) is widely applied to TM complexes, and “hybrid” DFT methods (including the widely used B3LYP) can provide reasonable accuracy for many TM properties at modest computational cost. New screened hybrid and “Rung 3.5” DFT functionals are designed to incorporate important aspects of hybrid DFT at reduced computational cost. We benchmark these functionals against a large data set of accurate experimental data for 3d TM complexes (J. Chem. Theory Comput. 2012, 116, 870-885). The predicted enthalpies of formation of the 3d TM molecules in the test set suggest that both classes of functionals can provide reasonable accuracy for TM thermochemistry.

CHED 554

Computational studies of transition states in bicyclic intermediates

Phillip Esempio,, Hernando Trujillo.Department of Chemistry, Wilkes University, Wilkes-Barre, PA 18766, United States

During 1,3 dipolar reactions of unsymmetrical mesoionic Münchnones (1) to substituted nitrostyrenes (2), bicyclic intermediates (3) are formed, which then decompose to two observed products (4, 5), the ratio of which is contrary to what would be expected based on known electrostatics. As part of a larger study of this set of reactions, a computational study of possible transition states, both to and from the intermediate, was conducted in order to clarify the mechanism by which this reaction occurs, and shed light on the unexpected ratio of products.

CHED 555

Predicted structures of aggregates of the human gamma-D crystallin protein found in cataracts

Sarah A. Richards,, Bao-Linh Nguyen, Ralph A. Wheeler.Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282, United States

Human age-onset cataracts are a disease caused by the aggregation of gamma-D crystallin, a structural protein in the lens of the eye. The resulting aggregation causes progressive blindness. The purpose of this research is to determine the causes of these aggregates and their resulting structures. It is hypothesized that a hydrophobic core, five contiguous hydrophobic residues, is critical for the aggregation of gamma-D crystallin. Initial molecular dynamics simulations of small peptides containing a hydrophobic core of gamma-D crystallin were performed to examine possible aggregate structures. Accurate structures of the aggregates will provide a basis for the long-term goal of designing drugs that will inhibit these aggregations to potentially prevent or treat cataracts.

CHED 556

Origin of enantioselectivity in helical dual hydrogen-bonding catalysts

Ulises Rangel,, Steven E. Wheeler.Chemistry, Texas A&M University, College Station, TX 77840, United States

Stereoselective reactions play an important role in chemistry, especially in the synthesis of pharmaceutical compounds. For this purpose, there are presently insufficient methods for asymmetric catalysis without the use of toxic and costly transition-metal based compounds. Here we report a computational study of the enantioselective addition of 4,7-dihydroindoles to trans-nitroalkenes catalyzed by a novel dual hydrogen-bonding helical catalyst recently developed by Takenaka and co-workers [J. Am. Chem. Soc. 2010, 132, 4536]. Through the use of density functional theory (DFT) methods at the B97-D/TZV(2d,2p) level, the mechanistic pathways for this reaction were explored to identify the key features of the transition state (TS). It is shown that the helical structure of the catalyst induces a stepwise mechanism through non-covalent interactions resulting in kinetic discrimination and high enantioselectivity. Ongoing studies involve application of the distortion-interaction model to quantify the role of these non-covalent interactions in the enantioselectivity. Understanding the salient features of this reaction is essential for the rational design of improved organocatalysts that utilize similar hydrogen-bonding interactions.

CHED 557

Binding of heparin oligosaccharides to proteins: Validating a computational methodology

Cynthia B. Lombardo1,, Christos Deligkaris2.  (1) Hoffman Department of Chemistry, Drury University, Springfield, Missouri 65802, United States  (2) Department of Physics, Drury University, Springfield, Missouri 65802, United States

Heparin glycosaminoglycans play an important role in many biological mechanisms such as metabolism, growth signaling, and metastasis. An understanding of the binding of heparin oligosaccharides to various protein receptors is impeded by the difficult process of fractionation and crystallization as well as by cost. Because of this, a computational method is highly desirable. To validate our computational method, we minimize a free energy function with the aid of a Lamarckian Genetic Algorithm (LGA) to compute the binding site of a heparin tetramer on a basic fibroblast growth factor (PDB code 1BFB) as well as other systems for which the binding site is known from crystal structures. The free energy function includes a van der Waals term, an electrostatic term with a distance-dependent dielectric function, a directional hydrogen bonding term, a solvation term, and a torsional term. We also systematically vary LGA parameters to achieve the best compromise between accuracy and efficiency.

CHED 558

1,3-Dipolar cycloadditions of azomethine ylides: Prospects for covalent functionalization of carbon nanotubes

Jacqueline M Maguire,, Jacob W. G. Bloom, Steven E Wheeler.Department of Chemistry, Texas A&M University, College Station, TX 77843, United States

The properties of single-wall carbon nanotubes (SWNTs) have become a prevalent topic of study in the scientific community in recent years. Covalent functionalization is used to tune their physical and electronic properties for applications in energy storage and optical devices, as well potentially separating metallic from semiconducting SWNTs. We investigated the 1,3-dipolar cycloaddition reactions of azomethine ylides with SWNTs using computational chemistry. Focal point analyses of the 1,3-dipolar cycloaddition reactions of the azomethine ylide with ethylene and benzene were compared with density functional theory (DFT) for use with larger systems [CCSD(T)/CBS vs. B3LYP-D/6-31G(d) and B97-D/TZV(2d,2p)]. These functionals were used as a benchmark for the same reaction with (6,6) SWNTs for two-layered ONIOM method geometries [B3LYP-D/6-31G(d) vs. B3LYP-D/6-31G(d)//B3LYP/6-31G(d):UFF and B97-D/TZV(2d,2p) vs. B97-D/TZV(2d,2p)// B97-D/TZV(2d,2p):UFF]. Future work will allow this method to be applied to larger systems, and adding substituents onto the ylide could alter the reactivity of the systems through stacking interactions.

CHED 559

Efficacy of transition metals as Sonogashira co-catalysts: Computation and experiment

Mercedes S. Black, Talia M. Fanelli, Alexis C. Konja, Mariam A. Saco, Michelle M. Smith, Ciara J. Viola, Jenna L. Wonsowicz, Matthew J. Mio,, Jonathan E. Stevens.Chemistry and Biochemistry, University of Detroit Mercy, Detroit, MI 48221-3038, United States

Ab initio molecular orbital and density functional calculations optimize the structures of complexes of acetylene to selected transition metal cations. These computations also determine the deprotonation energy of these complexes, and provide predictions about the efficacy of these cations as Sonagashira co-catalysts. These predictions are compared to the quantitative yields of synthetic attempts which implement these ions in the co-catalyst role. Correlation is observed between the theoretically-predicted acetylene complex energies and the utility of the transition metal co-catalysts as measured by percent yields in a common Sonogashira transformation.

CHED 560

Geometry optimizations with effective fragment potentials

Anthony J. Burand Jr.,, Andreas V. Copan,, Rollin A. King.Department of Chemistry, Bethel University, St. Paul, Minnesota 55112, United States

The effective fragment potential (EFP) method models discrete solvent molecules according to their electrostatic, polarization, dispersion, exchange-repulsion, and charge transfer effects, allowing for computational analysis of systems in a solvent environment within a reasonable time-frame. This project aims to integrate EFP with the optimizer of PSI4, an open source, ab initio quantum chemistry program. Implemented algorithms include GS2 (2nd order Gonzalez-Schlegel) reaction-path-following, RFO and P-RFO (partitioned rational function optimization), Newton-Raphson optimization, and steepest-descent minimization. Model systems used for comparison to the literature include water dimer and water-formamide.

CHED 561

Molecular docking studies of novel flavonoid derivatives as acetylcholinesterase inhibitors

Olivia M Newman,, Chavonda J Mills.Department of Chemistry, Physics, & Astronomy, Georgia College, Milledgeville, GA 31060, United States

Studies show that one of the many factors contributing to Alzheimer's disease is the hydrolysis of acetylcholine (ACh) from the enzyme acetylcholinesterase (AChE). Research has also found that AChE inhibitors decrease the rate at which ACh is metabolized, therefore increasing the concentration of ACh in the brain. Thus, the development of AChE inhibitors for the treatment of Alzheimer's disease is essential. The proposed research presents docking studies of novel flavonoid derivatives at the AChE active site. Autodock 4.0 as well as Autodock Vina were used to determine binding free energy and inhibitory concentration (IC50) values were calculated. The results will facilitate the design of novel flavonoid derivatives as AChE inhibitors.

CHED 562

Computational modeling of dietary dibenzoylmethane for targeting GR binding sites in hormone refractory prostate cancer

Lydia A Ruffner,, Leyte Winfield, Kimberly M Jackson.Department of Chemistry, Spelman College, Atlanta, GA 30314, United States

Prostate cancer continues to pose a public health challenge to the United States. It's the most commonly diagnosed cancer and second leading cause of cancer related deaths in U.S. males with approximately 240,000 new cases and 34,000 deaths in 2011. Initially, prostate cancer begins as an androgen-dependent tumor. Over time, prostate cancer eventually progresses or emerges to an androgen independent or refractory state for which there is no effective treatment. Small molecules such as dibenzoylmethane (DBM) which specifically target the glucocorticoid receptor (GR) signaling pathway may provide an effective treatment for hormone refractory prostate cancer. Computational and modeling data suggest that DBM interacts within different locations on the GR. Molecular models were constructed based on the crystal structure of human GR-LBD in the complex of a glucocorticoid (GC) ligand using the Molecular Operating Environment (MOE). Models were obtained from the Research Collaboratory for Structural Bioinformatics Protein Data Bank (RSCB PDB). Alternate binding sites for DBM based on DBM conformation within the GR-LBD binding pocket will be explored using the docking tool in the MOE software. Protein alignment will be utilized to compare the conformation of GR-LBD in complex with DBM and the conformation of the protein when a GC is bound. Binding affinities and conformation energies will be calculated for each ligand-protein complex for overall good fit. The amino acid sequence of the DBM-GR binding site will be determined using the sequence editor tool in MOE. This will provide information on changes in protein conformation and ligand affinity that occur in the presence of DBM.

CHED 563

Global optimization of carbon and boron nitride clusters using a genetic algorithm

Hallie Harbison,, Eric D Glendening.Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, United States

A genetic algorithm is a global optimization method that mimics the natural selection processes of evolution. Members of a population mate to form offspring which, according to their fitness, are either discarded or join the population. Mutations occasionally occur, and the resulting mutant offspring can potentially join the population too, whether they are fit or not. We have implemented a genetic algorithm that can be interfaced to Gaussian-09, GAMESS, or MOPAC9 to determine the geometry of a cluster of atoms corresponding to the global energy minimum. The algorithm uses a combination of mating, permutation, and mutation to maintain a population of candidate cluster geometries. Test cases reveal that the population tends to converge on the global energy minimum. We report results from semi-empirical and density functional calculations on small carbon and boron nitride clusters.

CHED 564

Sulfur dioxide adsorption at surfaces of ionic aqueous solutions

Omar Kyle Hite2,, Geraldine Richmond1, Kevin Johnson2.  (1) Materials Science Institute, University of Oregon, Eugene, OR 97403, United States  (2) Chemistry, Pacific University, Forest Grove, OR 97116, United States

Sulfur dioxide is a major atmospheric component and is introduced into the environment both naturally and industrially. However, under certain conditions, sulfur dioxide can cause acid rain and cloud nucleation. Therefore, it is imperative to understand how sulfur dioxide adsorbs onto aqueous surfaces at the molecular level and in particular, ionic aqueous solutions. This adsorption process was modeled using classical molecular dynamics, which provides a detailed picture of the adsorption process. From the simulation data we were able to perform statistical analysis to determine interfacial density and molecular orientation for both water and sulfur dioxide. It was found that relatively high concentrations of ions in the aqueous solution hinder the sulfur dioxide's ability to adsorb onto surface which decreases the solubility of the sulfur dioxide.

CHED 565

Resonance-assisted hydrogen bonding (RAHB) in carboxyphosphate by computed 31P NMR shielding constants and shifts

Sarah E. Kochanek1,, Teresa M. Dierks1, Steven M. Firestine2, Jeffrey D. Evanseck1.  (1) Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282, United States  (2) College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan 48201, United States

Resonance-assisted hydrogen bonding (RAHB) is a controversial phenomenon that describes flow of charge and π-system electrons, which can potentially modulate the strength of an intramolecular hydrogen bond. RAHB was investigated as a possible explanation for the unusually high stability (+11 kcal/mol) of the pseudo-chair conformation of dianionic carboxyphosphate. Using Truhlar's Minnesota M06-2X functional and Dunning's aug-cc-pVnZ (n=D,T,Q,5) basis sets, the 31P NMR shielding constants and chemical shifts have been calculated and compared to the analogous values for monohydrogen phosphate. 31P NMR properties were calculated for nine phosphorus systems with known experimental values with phosphoric acid and phosphine used as the reference systems. The calibration is used to validate the differences between carboxyphosphate's and hydrogen phosphate's chemical shifts. The computed difference of carboxyphosphate shifts, nucleus-independent chemical shifts (NICS) and relation to RAHB will be discussed as an explanation for the increased stability of dianionic carboxyphosphate.

CHED 566

Hydrogen bonding in substituted benzoates

Damen R Gee,, Kevin Range.Department of Chemistry, Lock Haven University of Pennsylvania, Lock Haven, Pennsylvania 17745, United States

The objective of this research is to determine whether or not there is hydrogen bonding in 5-bromo-2-(bromomethyl)-benzoic acid, ethyl ester (CAS Registry Number: 950741-84-1). Research has shown the possibility of an intramolecular hydrogen bond between a bromomethyl hydrogen and an ester oxygen. Density functional theory calculations were used to attempt to verify the above hypothesis. The 5-bromo-2-(bromomethyl)-benzoic acid, ethyl ester was not the only molecule studied, 5-bromo-2-(methyl)-benzoic acid, ethyl ester, water, and water dimers were also observed to better understand the possibility/characteristics of hydrogen bonding in molecules that are known to have these bonds or the possibility.

CHED 567

DFT study of the mechanism of the photo-oxidation of dihydrobiopterin in aqueous media

Crissie Vandehoef,, Christopher B. Martin.Department of Chemistry & Biochemistry, Lamar University, Beaumont, TX 77710, United States

Dihydrobiopterin (H2Bip) and biopterin (Bip) are two molecules in the pterin family that accumulate in the white patches of the skin in patients with the disease vitilgo. Using HPLC, fluormetric, and other techniques, Thomas and co-workers proposed an eleven-step mechanism by which H2Bip is photo-oxidized to Bip in aqueous media. (“Photochemistry of Dihydrobiopterin in Aqueous Solution”, Thomas Org. Biomol. Chem., 2010 , 8, 800-810.) In the present work, we present the results of a collaboration with the above mentioned authors where the proposed mechanism is investigated using Density Functional Theory (DFT) calculations. The calculations explore the various photochemical spin states (excited-singlet and -triplet states), electron-transfer reactions, and radical reactions using the PCM (Polarizable Continuum Model) for solvation using water as the dielectric constant for all species. These thermodynamic results, and their known limitations, are used to support the feasibility of the literature proposed mechanism.

CHED 568

Hydration of a coarse-grained methyl-ion solute

Marcus E Parry,, Tricia D. Shepherd.Department of Chemistry, Westminster College, Salt Lake City, Utah 84105, United States

Studying toxic methyl mercury in aqueous environments is essential to understanding mechanisms of food chain contamination. While there is much research investigating solute-solvent interactions of aqueous metal ions or nonpolar molecules in water, we are interested in the solution properties of a simple methyl-ion model developed to mimic the behavior of aqueous methyl mercury. Coarse-grained parameters for several hydrophilic ion-like particles without charge are presented representing metal ions Zn2+, Hg2+, Na+, and K+. Despite the use of only short-ranged interactions, the coarse-grained ion models accurately reproduce the solvation structure of each ion in reference to both experimental observation and atomistic molecular dynamics simulations. Molecular dynamics simulations of these hydrophilic ion particles bonded to a single hydrophobic methane-like particle in water surrounded by a vacuum were performed. Methyl-zinc and methyl-mercury models were found to exhibit more hydrophobic character than smaller charge methyl-potassium and methyl-sodium for a range of bond lengths.

CHED 569

Computational study of complexes between mercury (II) and tetra-peptides with N- and C-terminal cysteine amino acids

Diamond Nichols,, Joshua Watts, John K Merle.Department of Chemistry, Winston Salem State University, Winston Salem, North Carolina 27110, United States

Clinical chelation therapy compounds for mercury poisoning usually contain thiol moieties. Current chelation therapies administer dimercaptosuccinic acid (DMSA) and dimercaptopropanesulfonic acid (DMPS) as Hg2+ chelators. To improve upon current therapies, this present study seeks to better understand the complexation interactions of mercury (II) with cysteine (-CH2-SH side chain) containing tetra-peptides. Density functional theory (DFT) calculations using the M06-2X/6-31G(d,p)/SDD level of theory have been conducted to investigate structural and thermodynamic aspects of the interactions of mercury (II) with these peptide ligands. To improve complexation energy values MP2/6-311G**(cc-pVDZ-PP) single-point energies are determined on all structures. All calculations are performed using the SMD solvation model. To optimize complexation between mercury (II) and the tetra-peptides, the two internal amino acids are varied. The primary focus here is placed on the tetra-peptides cys-gly-gly-cys, cys-glu-gly-cys, cys-gly-glu-cys, cys-glu-glu-cys, including their stereoisomers.

CHED 570

Computational analysis of bryostatin 1: Difficulties, conformational energies, and analog reactivity differences

Joshua Dahlke,, Ron C. Estler.Department of Chemistry, Fort Lewis College, Durango, CO 81301, United States

Bryostatin 1 is a natural occurring product containing 47 carbon, 17 oxygen, and 68 hydrogen atoms. It is extracted from Bugula neritina, a species of bryozoans and has been found to be a modulator of protein kinase C. This discovery has lead to the compound being seen as a possible anti-cancer and memory-enhancing agent. Several analogs of Bryostatin 1 have been synthesized since its discovery. These analogs have not been as active medicinally. Using a variety of computational tools, the conformationally difficult portion of Bryostatin 1 was analyzed to explore reasons for its synthetic challenge. A variety of its analogs were similarly analyzed and these differences are presented.

CHED 571

Formation of stripe liquid crystal phases in water mixtures

Rita A Okumu, of Chemistry, Westminster College, Salt Lake, Utah 84105, United States

Liquid crystals have widespread applications in nano-optical and nano-electrical technology. We report simulations of water and a mildly hydrophilic solute that produce stripe liquid crystal phases. Using classical Molecular Dynamics simulations with the mW model of water, we determined the range of stability of this liquid crystal phase and quantified the ratio of water to solute in the stripes as a function of the strength of the water-solute attraction. In addition we investigated the effect of temperature and excess solute and water on these structures. These preliminary results contribute towards an understanding of the mechanism behind the formation of this novel phase of water.

CHED 572

Computational study of substituted anilines and indoles: The effect of intramolecular hydrogen bonding on N-H stretching frequencies

Shamus Driver,, Jason W Ribblett.Department of Chemistry, Ball State University, Muncie, IN 47306, United States

Through-bond and through-space interactions were examined on aniline and indole. On aniline, different groups were placed in the ortho, meta, and para positions with respect to the amino group. On indole, the substituents were placed in different positions of the six-member and five-member rings. Substituents included functional groups which contained a highly electronegative atom (F,O,N) capable of forming a hydrogen bond with an amino hydrogen atom as well as functional groups incapable of forming hydrogen bonds with the amino group. DFT and MP2 methods were used to determine ground state optimized geometries for multiple conformations of all compounds studied. Correlations found between the N-H stretching frequencies with the C-N bond length in the meta and para substituted anilines were not present in the ortho substituted anilines. A similar result was found in the substituted indoles.

CHED 573

Alkanethiols self-assembled monolayers on a GaAs(100) surface

Alyssa S Manz,, Heriberto Hernandez.Department of Chemistry, Grinnell College, Grinnell, IA 50112, United States

A computational study of a pentanethiol self-assembled monolayer adsorbed on a GaAs(100) surface was performed using the ONIOM method. The interaction of the pentanethiol and an embed cluster on the surface was optimized using the B3LYP/6-31+G(d) level of theory. The rest of the surface was model using a universal force field. On smaller clusters, the pentanethiol adsorbed slightly parallel to the surface, whereas on larger clusters with several thiols present, the adsorption was almost perpendicular. Results from this study showed that a large surface and multiple thiols on the surface are indeed necessary for an accurate description of a self-assembled monolayer.

CHED 574

Conformational analysis of cyclohexanone ring systems by DFT and other computational methods

Francisco Jimenez,, Randy M Miller, David B Ball.Department of Chemistry and Biochemistry, California State University, Chico, Chico, CA 95929, United States

The chair-chair interconversion of cyclohexane has been well characterized using a variety of experimental and computational techniques. Less well-studied are the cyclohexanone systems of increasing complexity including 3,3,5,5-tetramethylcyclohexanone and 2-bromo-3,3,5,5-tetramethylcyclohexanone. The potential energy surfaces, including intermediates an transition states, have been fully described using PM3, HF, DFT, MP2 and MP4 theories. In general, functionalizing cyclohexane to make the cyclohexanone and tetramethylated versions leads to more intermediates, a more complex energy landscape and lower transition state barriers.

CHED 575

Engineering novel self-assembling peptide materials by studying diphenylalanine

Carolyn Mills,, Joohyun Jeon, M. Scott Shell.Department of Chemical Engineering, University of California, Santa Barbara, Goleta, CA 93117, United States

The recently-discovered diphenylalanine peptide (FF) self-assembles into nanotubes with remarkable properties: exceptional stability to heat and solvents, and high mechanical strength. While experiments have investigated the properties and applications of FF nanotubes, little is known about their self-assembly mechanism or the intermolecular interactions underlying their stability.

Here, we use atomic-resolution simulations of FF peptides to gain insight into the early stages of oligomerization and the driving forces for assembly. Specifically, we use molecular dynamics simulations to characterize oligomers of FF peptides in aqueous solution. We measure contacts, dihedral angles, and structures, and compare to the putative experimental x-ray crystal structure of FF nanotubes. Our results suggest that both hydrophobic interactions between the phenylalanine side-chains and electrostatic interactions between their termini drive assembly of small oligomers. Ultimately, a deeper understanding of FF nanotube assembly should facilitate the functionalization and engineering of new synthetic peptide-based materials.

CHED 576

Discussion on the pentacoordinate complexes in VSEPR

Chenxi Zhang,, Xuefeng Wang.Department of Chemistry, Tongji University, Shanghai, Shanghai 200092, China

The Valence Shell Electron Pair Repulsion (VSEPR) model predicts the arrangement of five electron pairs is the trigonal bipyramid instead of the square pyramid in order to minimize their interactions. However, in our calculation, B3LYP/6-311++G(d,p) level of DFT was employed to comprehensively elucidate TaH5 prefers to the square pyramid arrangement but TaF5 has the trigonal bipyramid structure as VSEPR predicted. Moreover, there would be a greater repulsion such as lone pairs, less electronegative ligands and double bonds on the axial pairs than on the equatorial pairs of a trigonal bipyramid. In this paper, we attempt to discuss three controlling factors of molecular geometry: 1) the Pauli repulsion; 2) the metal d orbital participation in σ bonding and 3) ligand electrostatic repulsion.

Fig 1. a) the square pyramid structure (C4v) of TaH5; b) trigonal bipyramid structure (D3h) of TaF5

Fig 2. Example of pentacoordinate molecules in which the less electronegative ligands and double bonds occupy the equatorial positions

CHED 577

Generation of secondary organic aerosol from a beta-phellandrene based essential oil

Kaylee Gund1,, Kara Huff Hartz2.  (1) Department of Chemistry, University of Dallas, Irving, TX 75062, United States  (2) Department of Chemistry and Biochemistry, University of Southern Illinois, Carbondale, IL 62901, United States

When released into the atmosphere, volatile organic compounds (VOCs) react with oxidants to form secondary organic aerosol (SOA). SOA comprises a significant portion of total organic particulate matter and poses environmental and health hazards with increasing concentrations. SOA formation from a byproduct of mountain pine beetle infestations in lodgepole pine tree trunks, a VOC called β-phellandrene, was investigated. To study this phenomenon, an essential oil containing β-phellandrene and minor amounts of other VOCs was injected into an environmental smog chamber and allowed to react with an excess of ozone. SOA formation was measured by monitoring particulate matter formation using a scanning mobility particle sizer. SOA samples were collected onto filters for off-line characterization using solvent extract and analysis by gas chromatography/mass spectroscopy. Based on the kinetics of VOC oxidation and particle formation, β-phellandrene likely undergoes a two-step oxidation process during which products from both the endo and the exo carbon carbon double bond are formed. Analysis of filter samples collected during the experiment revealed that the carbon-carbon double bonds of β-phellandrene were oxidized to give a variety of products including cryptone. The measured SOA yields suggest that the β-phellandrene released from mountain pine beetle infestations has the potential to contribute to organic atmospheric particulate matter concentrations.

CHED 578

Determination of products formed by the photolysis of 2,4-dinitrotoluene and 2,6-dinitrotoluene in solutions containing dissolved ionic compounds

Alec J Kersey,, Daniel W. O'Sullivan, Dianne J. Luning Prak.Chemistry, United States Naval Academy, Annapolis, MD 21402, United States

The corrosion of unexploded ordnance casings at shooting ranges or dumping grounds provides an entry for munitions constituents into the marine environment. Exposure of these dissolved compounds to sunlight can cause some of them to degrade into products that are more toxic than the parent compound. In this work, some of the products formed by photolysis of two common propellants, 2,6-dinitrotoluene (2,6-DNT) and 2,4-dinitrotoluene (2,4-DNT), in seawater and salt water solutions were separated and identified. Solutions containing 2,4-DNT or 2,6-DNT were photolyzed using a solar simulator. The product mixtures were extracted on amino and C-18 solid phase extraction cartridges and sequentially eluted using water, acetonitrile and methanol. The extracts were analyzed using liquid chromatography mass spectrometry. The photolysis products that have been identified for 2,6-DNT include 2,6-dinitrobenzyl alcohol, 2,6-dinitrobenzaldehyde, and 2,6-dinitrobenzyl nitrile. The photolysis products that have been identified for 2,4-DNT include 2,4-dinitrobenzyl alcohol, 2,4-dinitrobenzaldehyde, and 2,4-dinitrobenzyl nitrile.

CHED 579

Determination of the impact of dissolved inorganic and organic substances on the photolysis of munitions constituents

Elizabeth A. Milewski,, Dianne J. Luning Prak.Department of Chemistry, United States Naval Academy, Annapolis, MD 21402, United States

Munitions constituents enter natural waters from the corrosion of unexploded ordnance casings and from runoff near shooting ranges. Exposure to sunlight can cause some of these constituents to degrade. In this study, the photolysis rates of two common propellants, 2,4-dinitrotoluene and 2,6-dinitrotoluene, were measured as a function of dissolved ionic and organic substances. Samples were exposed to simulated sunlight using a Suntest CPS+® solar simulator under various filters designed to select specific regions of the solar spectrum to examine the wavelength dependence of photolysis. After irradiation, samples were analyzed via HPLC, and first-order rate constants for the photolysis reaction were determined. The rates of photolysis increased with increasing concentration of dissolved ionic compounds. Photolysis rates in the presence of dissolved organic substances were faster than in pure water. This poster will present the rates of degradation of munitions constituents in waters containing various dissolved substances in varying concentrations.

CHED 580

Synthesis and oxidative degradation 6-(hydroxymethyl)uracil as a model compound for cylindrospermopsin (CYN), a potent cyanotoxin

Michelle Luzi,, Cen Zhao, Kevin O'Shea.Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States

Cylindrospermopsin (CYN) is a toxin produced by several strains of cyanobacteria which inhabit fresh water lakes and rivers. Algal blooms have received considerable attention because of the concerns with the elevated levels present in drinking water reservoirs. An effective and efficient method for eliminating CYN from drinking water supplies is critical to protect human and environmental health. The limited availability and high cost of high CYN have inhibited detailed studies on the removal or degradation of CYN by advanced oxidation technologies. With this in mind, 6-(hydroxymethyl)uracil has been synthesized as a model compound for CYN. Two synthetic approaches were followed in attempts to obtain the model compound. The model compound was subjected to photocatalysis using different types of TiO2 materials. The synthesis and degradation studies will be presented. We are currently attempting the synthesis of anticipated byproducts of the degradation reaction for confirmation product structures.

CHED 581

Atrazine degradation in Puerto Rico soil amended with compost and vermicompost

Manuel García,, Myrna Ríos, Angela Gonzalez.Department of Biology, Chemistry and Environmental Sciences, Inter American University of Puerto Rico - San Germán, San Germán, Puerto Rico 00683, Puerto Rico

Atrazine is a widely used pesticide because its efficiency and low cost to control weeds in crops. It has been used in Puerto Rico in pineapple, yams, yautias and banana crops. However, EPA has restricted its use due to its potential health risks for humans and aquatic ecosystems. Atrazine has been found in surface, ground, and drinking waters, especially after heavy rains. Soil amendment has been successfully used to stimulate the degradation of contaminants. This work compared the effectiveness of amending soil with grass clippings compost or vermicompost to reduce atrazine concentration. Decrease in the concentration of atrazine was followed using UV detection after extraction of the pesticide. UV detection allowed a simple way to follow atrazine concentration through the experiment. Results indicated that vermicompost amendment reduced the atrazine concentration by more than half, in the period of the study, being the most effective modification.

CHED 582

Removal of arsenic and chromium in groundwater using a magnetite based nanocomposite

Manuel García1,, Tatiana Luna-Pineda2, Oscar Perales-Pérez3, Félix Román-Velázquez2.  (1) Department of Biology, Chemistry and Environmental Sciences, Inter American University of Puerto Rico, San Germán, PR 00683, Puerto Rico  (2) Department of Chemistry, University of Puerto Rico, Mayaguez, PR 00681, Puerto Rico  (3) Department of Engineering Science & Materials, University of Puerto Rico, Mayaguez, PR 00681, Puerto Rico

The capacity of meso-dimercaptosuccinic acid functionalized magnetite (DMSA-magnetite) and magnetic nanocomposite (DMSA-magnetite as disperse phase and calcium alginate as matrix) to remove oxyanions is presented. For arsenic and chromium sorption a maximum uptake capacity was observed using a pH of 6.5 and 4.5, respectively. These results have been obtained using deionized water spiked with arsenic or chromium. Effect of DMSA-magnetite nanoparticles and magnetic nanocomposite on the removal of arsenic and chromium from ground water was investigated at pH 6.5 and 4.5, respectively. Water samples were taken from Mayagüez, Puerto Rico and spiked with different concentrations of arsenic and chromium. Samples were treated with 1g of sorbent per liter of water. The samples were shaken and aliquots were taken at regular time intervals (1, 6, 12, 24, 36, 48, 60, and 72 hours). The samples were diluted and concentrations of arsenic and chromium were determined using EPA method 200.8.

CHED 583

Arsenic sequestration from surface water via ZVI and copper nanoparticle filters

Angelica A Campos1,, Edgardo O Ortiz1, Jenifier Olavarria2, Marco A De Jesus2.  (1) Department of Biology, Chemistry and Environmental Science, Inter American University of Puerto Rico, San German, PR 00683, Puerto Rico  (2) Department of Chemistry, University of Puerto Rico, Mayaguez, PR 00681, Puerto Rico

Organoarsenic drugs, such as roxarsone and arsanilic acid, are commonly administered to control coccidian intestinal parasites and improve growth and pigmentation in poultry. These veterinary drugs can promote native bacterial resistance and degrade in the environment, releasing potentially more toxic arsenic species (As (III) and As (V)). Ninety five percent of arsenic drugs are released into litter which is commonly used as fertilizer, thus raising concerns regarding possible dispersion of arsenic to water bodies. Copper and iron nanoparticles have proven to be highly effective for arsenic absorption; therefore, their use as isolating materials is attractive. In this work, filters containing metallic Fe and Cu nanoparticles were developed to evaluate their removal capability of roxarsone and arsanilic acid. The removal capability of the new filters was assessed by determining the organoarsenic drugs concentration, by HPLC. Results indicate that zero valent iron filters (ZVI) were more effective to remove those drugs.

CHED 584

Investigation of toxic heavy metals in the Chattahoochee River water using graphite furnace atomic absorption spectroscopy

Timothy C Jones,, Samuel Abegaz.Department of Chemistry, Columbus State University, Columbus, Ga 31907, United States

The Chattahoochee River is approximately 430 miles long. It is important to Alabama, Georgia, and Florida. Pollution of the Chattahoochee River is a major concern, especially for cities such as Columbus which is located downstream from Atlanta. In this study, 15 water samples were collected from Eufaula, Alabama, to Lake Lanier, Georgia, and tested for the content of heavy metals using graphite furnace atomic absorption spectroscopy. The pyrolysis and atomization temperatures were optimized with and without matrix modifiers. The analytical procedure was validated using certified reference material and the results were in agreement with the certified values. The ranges of heavy metal concentrations ND – 0.215 μg/L, ND - 2.49 μg/L, ND - 3.2 μg/L, and ND – 4.6 μg/L for cadmium, chromium, arsenic, and lead, respectively, with a precision better than 5% for more than 95% of the measurements.

CHED 585

Insights into the solvolytic mechanism of α-chloro-2-(trifluoromethyl)benzyl chloroformate

Kaylee Miller1,, Catherine Gross1,, Malcolm J D'Souza1, Dennis N Kevill2.  (1) Department of Chemistry, Wesley College, Dover, DE 19901, United States  (2) Department of Chemistry & Biochemistry, Northern Illinois University, DeKalb, IL 60115, United States

Substituted benzylic chloroformate esters have found wide commercial use in the agrochemical, pharmaceutical, and the related chemical product industry. Additionally, peptide chemistry utilizes protecting groups such as the benzyloxycarbonyl group due to its chemical stability and ease of removal. In this undergraduate research project, the specific rates of solvolysis of α-chloro-2-(trifluoromethyl)benzyl chloroformate have been measured in several pure and binary aqueous organic solvents including a variety of fluoroalcohol mixtures. The kinetic rates of this benzyl chloroformate containing electron-withdrawing substitution were determined using acid-base and conductometric titrations. Our results indicate that nucleophilic attack plays an important part in the rate-determining step. The Wesley College undergraduate research program in chemistry is supported, in part, by the Delaware INBRE and EPSCoR programs ‐ supported by grants from the National Center for Research Resources‐NCRR (5P20RR016472‐12) and the National Institute of General Medical Sciences ‐ NIGMS (8 P20 GM103446‐12) from the National Institutes of Health (NIH); a National Science Foundation (NSF) Delaware EPSCoR grant EPS‐0814251; and a NSF ARI‐R2 grant 0960503.

CHED 586

Differentiating electronic effects in substituted aryl chlorothionoformate esters

Brett M Sansbury1,, Malcolm J. D'Souza1, Dennis N. Kevill2.  (1) Department of Chemistry, Wesley College, Dover, DE 19901, United States  (2) Department of Chemistry & Biochemistry, Northern Illinois University, DeKalb, IL 60115, United States

Aryl chlorothionoformates (ROCSCl) are derivatizing agents that have also found wide use in the preparation of thionocarbamates that are effective fungicides. Over the past few years, our research group has analyzed in detail the solvolyses of p-tolyl-, phenyl-, p-chlorophenyl-, p-fluorophenyl-, and pentafluorophenyl chlorothionoformate esters in a variety of organic mixtures of widely varying nucleophilicity and ionizing power values. Here we present all of the solvolytic data of pentafluorophenyl chlorothionoformate accumulated at 25.0°C using the titration method. The rate data show that there is a significant dependence on substitution effects and an analysis using the extended (two-term) Grunwald-Winstein equation shows the occurrence of simultaneous side-by-side addition-elimination and unimolecular SN1 mechanisms. This work is supported, in part, by the Delaware INBRE and EPSCoR programs ‐ supported by grants from the National Center for Research Resources‐NCRR (5P20RR016472‐12) and the National Institute of General Medical Sciences ‐ NIGMS (8 P20 GM103446‐12) from the National Institutes of Health (NIH); a National Science Foundation (NSF) Delaware EPSCoR grant EPS‐0814251; and a NSF ARI‐R2 grant 0960503.

CHED 587

Microbial fuel cell as a tool for chemical education

Venkataramana Gadhamshetty1,, Wendy M. Willner1,2,, Marianne Nyman1, Anne P Hynes3.  (1) Department of Civil and Environmental Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, United States  (2) Briarcliff High School, Briarcliff Manor, New York 10510, United States  (3) Material Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States

3,3' Dichlorobenzidine (DCB) represents a carcinogenic compound that was frequently used in manufacturing of textiles and dyes until 1982. This study evaluates the viability of bioelectrochemical reduction of DCB compounds in biocathodes of microbial fuel cells (MFCs). In MFCs, exoelectrogenic bacteria oxidize organics in the anode,and generate electrons that can be used to reduce oxidized contaminants in the cathode. A glass H-type reactor, utilizing DCB in a biocathode, was operated for nearly three months. The MFC produced nearly 1.08 mW/m2 while reducing DCB. The DCB concentration was reduced by nearly 23.9% within first 24 hours of operation. Impedance analysis indicated a solution resistance of 150 Ω, a polarization resistance of 650 Ω, and showed presence of two time constants.

CHED 588

Examining arsenate/arsenite ratios in well water

Daniel S. Mast,, Arwyn Smalley.Department of Chemistry, Saint Martin's University, Lacey, Washington 98503, United States

Arsenic is a major water quality issue in communities around the world. Arsenic
is present in natural waters as one of two ions: arsenate(IV) and
arsenite(III). Residents of most counties in Washington State, including San
Juan County, are required to test for total arsenic concentration, without
regard to the speciation, although the two ions have significantly different
toxicities. We used a molybdenum blue method to test for both total arsenic
concentration and the arsenic ion ratios in Lopez Island well water.

CHED 589

Quantitative determination of antidepressants in biosolids destined for land application

Lydia M Niemi,, Melissa M Schultz.Department of Chemistry, The College of Wooster, Wooster, OH 44691, United States

Antidepressants are one of the most widely dispensed class of pharmaceuticals in the United States. The use of biosolids, sludge produced from wastewater treatment plants, as fertilizer is a potential route for antidepressants to enter the terrestrial environment. A microextraction method was developed for the extraction of a suite of antidepressants in lagoon sludge destined for land application. Liquid chromatography tandem mass spectrometry was coupled with the extraction technique for quantitative determination. The method was applied to monthly lagoon sludge collected from June 2012 to February 2013. Labeled fluoxetine spiked sludge recoveries resulted in 50 ± 9% due to the heterogeneous nature of the sludge. Sertraline, fluoxetine, and citalopram were the most commonly detected antidepressants in the sludge samples. Concentrations of the individual antidepressants in the lagoon sludge ranged from no detect to 0.2 μg/kg (sertraline).

CHED 590

Nickel concentrations in sediments collected from the U.S. continental shelf in the Gulf of Mexico

Rachel K Gibbs,, Al C Nichols, David A Steffy, Larry J Morgan.Department of Physical and Earth Sciences, Jacksonville State University, Jacksonville, Alabama 36265, United States

Sediment samples were collected during the fall, 2010, along the U.S. continental shelf in the Gulf of Mexico. Bottom samples were collected using a Shipek grab sampler. Dried samples were analyzed for nickel using ICP. Nickel is a trace metal component of the crude oil released from the BP Deepwater Horizon oil spill in April 2010. The release of this crude oil could provide a new source of trace metals to the sediments forming the continental shelf. Carbonate sediments collected off of the Gulf coast of Florida had a mean nickel concentration of 5.31 + 3.81 micrograms of nickel per gram of dry sediment. Deltaic sediments collected off of the Louisiana coast had a mean nickel concentration of 9.09 + 3.58 micrograms /g.

CHED 591

Alternative mechanism for the kinetics of the aqueous formation of N-chloro-N-methylacetamide

Bridget J. Gromek,, Edward T. Gray,.Department of Chemistry, University of Hartford, West Hartford, Connecticut 06117, United States

The kinetics of the reaction of N-methylacetamide with aqueous chlorine is reinterpreted in a way that does not require the general-acid catalyzed pathway to proceed through an acyl-hypochlorite intermediate. This new approach limits the chlorinating species to aqueous HOCl and Cl2. The Cl2 reaction proceeds without catalysis while the HOCl pathways are both specific and general-acid catalyzed. However, the catalytic step invokes a modification of the amide nitrogen to a more amine-like entity which can then react rapidly with HOCl along the lines of the well-known mechanism of acid catalysis of the hydrolysis of secondary amides. Rate constants for the reaction with Cl2 will be presented as well as those for the specific-acid and general-acid catalyzed pathways involving HOCl. The HOCl reactions are accomplished without the presence of chloride ion to eliminate interference from the Cl2 pathway.

CHED 592

Kinetics and mechanisms of the reaction of amines with N-chloro-N-methylacetamide

Sarah C. Wahab,, Edward T. Gray.Department of Chemistry, University of Hartford, West Hartford, Connecticut 06117, United States

The kinetics and mechanisms of the transfer of oxidizing chlorine from N-chloro-N-methylacetamide to primary and secondary amines in aqueous solution will be presented. The reactions result in the quantitative formation of the respective chloramine over a wide pH range. The orders of the reaction with respect to each species will be presented along with a mechanism that includes the various dependencies of hydrogen-ion catalysis. The results will be discussed in terms of the conditions necessary to generate chloramine disinfectants in natural water systems using N-chloro-N-methylacetamide as a stable source of chlorine.

CHED 593

Direct synthesis of biodiesel fuel from tree nuts

Katie E. Benjegerdes,, John J. Stankus, of Chemistry, University of the Incarnate Word, San Antonio, TX 78209, United States

Biodiesel fuel was synthesized directly from solid nut sources including pecans and almonds in the absence of the intermediate step of pressing out the oil. The residual carbohydrates were fermented to produce the alcohol for the base-catalyzed transesterification reaction. The biodiesel was characterized by combustion calorimetry, GC-MS, and FTIR analysis.

CHED 594

Continued studies on the hypochlorite of phenol

Tina Moulton,, Justin Hsu,, Luke Vickers, Vic Heasley.Department of Chemistry, Point Loma Nazarene University, San Diego, California 92106, United States

The synthesis and isolation of the organic hypochlorite, formed by the reaction of monochloramine and phenol in water, has been improved. After formation, the hypochlorite is extracted into ether and isolated by repeated vacuum removal of the monochlorine. The presence of this structure in the solution was confirmed via iodometric titration, gas chromatography, and mass spectrometry. The structure of the hypochlorite was confirmed using 1H-NMR, in which the hypochlorite was isolated under vacuum, placed in the 1H-NMR, reduced, dried, and placed again in the 1H-NMR. The structure was also confirmed using 13C-NMR. The hypochlorite reactivity was probed by analyzing the aqueous reaction of the hypochlorite with various hydrocarbons commonly found in drinking water. The hypochlorite did react with these hydrocarbons when in an acidic solution and, to a small extent, in a neutral solution.

CHED 595

Mercury analysis in Rafinesque big-eared bat populations

Lara J. van der Heiden,, Cathleen J. Webb.Department of Chemistry, Western Kentucky University, Bowling Green, Kentucky 42101, United States

Mercury (Hg) from atmospheric deposition from coal-burning power plants and other anthropogenic sources was analyzed in Rafinesque Big Eared Bats from Mammoth Cave National Park. The mercury from water progressively moves up the food chain through insects, and eventually into bats. In 2011, 58 bats were collected and hair samples were taken for an analysis. The AMA254 Mercury Analyzer was used to determine the mercury concentration from the bat hair in parts per million. A considerable amount of mercury was discovered in the bats analyzed. The mercury concentration of juvenile Rafinesque bats averaged between 0.5-1.0 ppm. Mercury levels in adult Rafinesque bats averaged between 1.0-2.0 ppm, with female bats overall containing the highest amount of mercury. Notably, the mass and forearm length of Rafinesque bats do not appear to affect the amount of mercury the bats contain.

CHED 596

Photocatalytic degradation of triclosan

Owen D Williams,, Dwight J Tshudy, Joel E Boyd.Department of Chemistry, Gordon College, Wenham, MA 01984, United States

Triclosan is a common substance in personal care products and is an emerging concern with regard to its potential environmental and human health effects. Triclosan was chosen as a photocatalytic degradation target because it is often considered to be a representative compound for the broader class of pharmaceutical waste products. Triclosan will be quantified using HPLC detection. Novel TiO2-acrylic composite reactors will be applied to the photocatalytic degradation of triclosan for potential point-of-use applications in high triclosan usage areas.

CHED 597

Porous TiO2/acrylic composite materials for the photocatalytic oxidation of carbon monoxide

Lee G Andrews,, Benjamin D Stewart, Clyde A Daly, Joel E Boyd.Department of Chemistry, Gordon College, Wenham, MA 01984, United States

TiO2 is well-known as a photocatalyst that can oxidize organic molecules when activated by UV light. The deposition of TiO2 within UV-transparent porous support materials facilitates the construction of efficient flow-through photocatalytic reactors for gas-phase applications. Carbon monoxide (CO), an odorless tasteless gas that can be lethally toxic to humans, is a byproduct of incomplete combustion reactions such as automobile exhaust. This study shows that the porous polymer wafer reactors fabricated in our lab can be used for the photocatalytic oxidation of CO into CO2 in the presence of O2. The photocatalytic activity of platinized and a non-platinized reactors are compared using various illumination intensities and wavelengths, in order to investigate the viability of such reactors for use in industrial and household applications.

CHED 598

Novel solvent bar microextraction of acetaminophen and azithromycin from water

Cody L Smith,, Edward R Acheson.Department of Chemistry, Millikin University, Decatur, Illinois 62522, United States

A 2000 study done by the United States Geological Survey (USGS) analyzed 139 water samples from various streams across the United States. 95 different compounds, ranging from steroids to antibiotics, were found at part per billion (ppb) levels in the samples. In order to detect these compounds, it was first necessary to concentrate the analytes using solid phase extraction (SPE). While SPE is useful for concentrating these analytes, the process is tedious, time-consuming, and not reproducible. Solvent bar microextraction, first described in 2004, can be used as a rapid and reproducible alternative to SPE. We have successfully used solvent bar microextraction to concentrate acetaminophen from water as a model system for concentrating the antibiotic azithromycin. We will describe our results with acetaminophen as well as preliminary results concentrating azithromycin.

CHED 599

Determining volatiles produced by decomposing carcasses using GC/MS

Jordan Fauser,, Donald Wharry, Kendra Abbott.Department of Chemistry, St. Edward's University, Austin, Texas 78704, United States

The Nicrophorus carolinus is a species of carrion beetle found in the United States which uses chemical signals to locate carcasses at the ideal age for brood ball formation. Based on field observations the beetles appeared to be most attracted to carcasses 4 days into the aging process. The focus of this research was creating a profile of the compounds produced by the decomposing carcass which attract these carrion beetles using Solid-phase micro-extraction and gas chromatography with mass spectroscopy. Volatiles from chicken and mouse carcasses were tested, aged in the same way, and tested over a one week period, focusing on days 2-5 of the aging process. Samples from whole carcasses and parts were tested. Differences were identified in the compounds released based on the three variables tested. The compounds most consistently observed were identified and some quantifications were conducted to determine changes in extent of compounds released over time.

CHED 600

Analysis of heavy metal concentrations within street dust of the Long Creek watershed

David Finocchietti1,, Sarah McClain1, Martin Stein1, Lucille Benedict1, Kate McDonald2.  (1) Department of Chemistry, University of Southern Maine, Portland, Maine 04104, United States  (2) Cumberland Country Soil & Water Conservation District, United States

The objective of this research was to analyze for sources of contamination of the Long Creek Watershed in South Portland, ME. Pollutants tend to be transported by rainwater along roadways and into storm drains. The runoff due to this process is a detriment to aquatic ecosystems. This project aimed to investigate the concentrations of heavy metals in street dust by monitoring specific locations within the watershed and assessing trends over time. Samples were analyzed using an x-ray fluorescence spectrophotometer. The results of this research will be used to determine how to better manage urban runoff contamination into bodies of water, including the Long Creek Watershed.

CHED 601

Microbial fuel cells: Generating electricity from mud

Wayne Michael Schmitt1,2,3,, Pu Zheng1,2, Cheng Wen-Yen2, Yan Cao1,2, Hou-Yin Zhao2, Wei-Ping Pan1,2.  (1) Chemistry, Western Kentucky University, Bowling Green, Kentucky 42101, United States  (2) Institute of Combustion Science and Environmental Technology, Bowling Green, Kentucky 42101, United States  (3) Carol Martin Gatton Academy of Math and Science in Kentucky, Bowling Green, Kentucky 42101, United States

Our society faces a transition from the traditional fossil fuel energy supply to the extended wide-spectrum renewable energy supplies. This study explores the likelihood of electricity generation using bacterium metabolism, while simultaneously cleaning up the wastewater. Organic contaminants in wastewater are the energy source for the metabolism of bacterium, yet some trace metal is vital. Demonstrated in the laboratory using test tubes and beakers filled with mud and water, the naturally-collected bacteria can create electricity potential through the redox reactions of their metabolic activities. Bacteria generate a flow of electrons which can be potentially harvested as electricity. By altering the conditions in which these bacteria reside, it is possible to affect their metabolic activity, thus improving efficiencies of these microbial fuel cells. At the current stage of this study, only electricity potential is created, and further studies will focus on maintaining the constant electricity current in the microbial fuel cells.

CHED 602

Calcite precipitation and geochemistry in a calcareous fen

Krystal L. Woda,, Joseph J. Piatt.Department of Chemistry and Biochemistry, Carroll University, Waukesha, Wisconsin 53186, United States

Seasonal calcite precipitation dynamics were investigated at a calcareous fen (Vernon Marsh) in Mukwonago, Wisconsin. Calcareous fens are fed by groundwater in contact with dolomite, CaMg(CO3)2. As such, plant life in these fens has adapted to growing in the presence of high calcium and alkalinity. For each five-week sampling episode over the summer and fall, marble tiles were placed at a groundwater discharge area and at ten locations downstream. The tile mass gained or lost was used as an indicator of calcite precipitation or dissolution. Additionally, measurements of alkalinity, pH, CO2, dissolved O2, conductivity, and water temperature also were taken to understand the fen's surface water geochemical characteristics. Preliminary data suggests that in summer months there is calcite precipitation which corresponds with CO2 exolution and increases in pH as you move downstream from the discharge source. In colder temperatures we expect to measure calcite dissolution.

CHED 603

Amine incorporation into particulate matter at a California dairy

Kopano L Ramsay1,, Su Anne Lee1, David R Cocker2, Philip Silva3, Alam S Hasson4, Shawn Ashkan4, Kathleen L Purvis-Roberts1.  (1) Department of Chemistry, W. M. Keck Science Center, Claremont, California 91711, United States  (2) Center for Environmental Research & Technology, University of California, Riverside, Riverside, California 92521, United States  (3) Agricultural Research Service, United States Department of Agriculture, Bowling Green, Kentucky 42104, United States  (4) Fresno State University, Fresno, California 93740, United States

Particulate Matter (PM2.5) is a mixture of solid particles and liquid droplets in the atmosphere. It has adverse effects on the environment and human health. One of the chemical components of secondary organic particulate matter is alkylamines, but little is known about how they partition between the gas and particle phase. One of the major sources of these alkylamine emissions are in places of animal husbandry. A Particle-Into-Liquid-Sampler coupled to two Ion Chromatograms (PILS-IC) was used to identify and measure the concentrations of ambient inorganic amine cations and anions at Flint Dairy in Hanford, CA. A weather station was used to measure real-time daily weather conditions, including relative humidity, temperature, wind speed, and wind direction. Temperature and humidity fluctuated inversely. Almost all amine concentrations fluctuated over the course of the day. Sulfate, ethylamine, dimethylamine and triethylamine went up with increasing temperature, while nitrate concentrations went up with decreasing temperature.

CHED 604

Determination of stimulant use by commercial truck drivers: Wastewater analysis by LC-MS/MS

Rebecca L. Ferrell,, Daniel A. Burgard.Department of Chemistry, University Puget Sound, Tacoma, WA 98416, United States

Professions that require people to stay awake for long shifts, such as commercial truck drivers, have the incentive to abuse stimulants such as those from the amphetamine family. Usage statistics of these drugs comes from self-reporting data, police records and drug testing results. Self-reporting illicit drug use is inherently problematic and the other methods are invasive and involve catching use of the drugs. For this study wastewater was collected from portable toilets at a weigh station along Interstate 5 in Washington State. Daily samples were taken over a week, extracted using Solid Phase Extraction and analyzed for amphetamine, methamphetamine, pseudoephedrine and ephedrine by LC-MS/MS. Concentrations found in the wastewater were normalized using the human marker compound creatinine as well as a tally of facility users. Levels of amphetamine and methamphetamine were found to be as high as 120 and 660 ng/ml respectively.

CHED 605

Correlation between formation of alkylaminium salts in particulate matter on dairies

Su Anne Lee1,, Kopano Ramsay1, David R. Cocker2, Philip J. Silva3, Alam S. Hasson4, Shawn Ashkan4, Kathleen L. Purvis-Roberts1.  (1) W.M. Keck Science Department, Claremont Colleges, Claremont, California 91711, United States  (2) Center for Environmental Research and Technology, University of California Riverside, Riverside, California 92507, United States  (3) United States Department of Agriculture, Agriculture Research Service, Bowling Green, Kentucky 42104, United States  (4) California State University Fresno, Fresno, California 93740, United States

Gaseous amines in the atmosphere derive from sources such as sewage treatment and livestock feeding. These amines react in the atmosphere to form particles, specifically amine salts. Experiments were conducted at Flint Dairy, Hanford, CA to identify which amine salts are present in particulate matter, and to explore the possible correlation of alkylammonium salt formation. A Particle Into Liquid Sampler-Ion Chromatograph (PILS-IC) was used to identify and measure the concentrations of salts formed during our experimental period. The amines of interest are methylamine, ethylamine, dimethylamine, and trimethylamine, as well as the chloride, nitrate and sulphate anions. Data showed that over the period of a week, ethylamine correlates with the anions more than the other amines. Our findings also indicate that in the case of trimethylamine, there was a negative correlation with some of the anions.

CHED 606

Determination of pKa values for synthesized thiosemicarbazone and semicarbazone ligands

Jacob D Buckner,, Amanda J Crook, Dale D Ensor.Department of Chemistry, Tennessee Technological University, Cookeville, TN 38501, United States

Thiosemicarbazone and semicarbazone compounds have been extensively reported in scientific literature. These compounds are used as chelating agents and are being tested as possible cancer fighting agents. This research serves to determine the pKa values of the hydrazinic proton. This proton must be removed prior to metal chelation. These values provide valuable information in determining what pH range these compounds will be most effective at remediating metal ions out of aqueous solutions. This allows selection of ligands that will be successful in chelating metal ions out of natural water supplies at environmental pH ranges. These determinations will be conducted using spectroscopic methods that determine changes between protonated and deprotonated forms of the ligand as pH is varied. This class of compounds is expected to be effective in the pH range of natural water supplies, as preliminary data places the pKa values of the compounds in the range of pH 8.

CHED 607

Baseline water quality monitoring in the watersheds of Otsego County, NY

Nicole Daniels,, Martina Yoshiko,, Zsuzsanna Balogh-Brunstad.Department of Chemistry, Hartwick College, Oneonta, New York 13820, United States

The Marcellus Shale is a Middle Devonian age, black, low density, organic rich shale that contains about 1.9 trillion cubic feet of natural gas that could be produced by the process of horizontal hydraulic fracturing (fracking). One of the environmental effects of fracking is potential surface and ground water contamination. Establishment of baseline water quality information is essential for various parameters to allow detection of any changes caused by fracking. The goals of our study are to monitor chemical and physical field parameters and to establish a baseline database of current heavy metal concentrations of the surface waters. Water samples are collected every three weeks for nine months at fifty sites in Otsego County, NY and heavy metal concentrations are determined using atomic absorption spectroscopy. All collected results will be used to produce maps that show the current chemical state of the surface waters throughout Otsego County.

CHED 608

Bioremediation technology using Lentinula edodes and Phanerochaete chrysosporium to remove trace levels of 17-α-ethinylestradiol in wastewater

Hannah A Chappell1,, Lori Coward2, Greg Gorman2, Denise J Gregory1.  (1) Department of Chemistry and Biochemistry, Samford University, Birmingham, AL 35229, United States  (2) McWhorter School of Pharmacy, Samford University, Birmingham, AL 35229, United States

The presence of 17-α-Ethinylestradiol (EE2) in the environment is causing harmful effects on the ecosystems around wastewater. Certain strands of fungi have been proven to degrade complex molecules such as Bisphenol A and lignin. Two strands of fungi were used, Lentinula edodes and P. chrysosporium to degrade EE2. Both fungi have lignolytic enzymes that are important in the degradation process. Lentinula edodes contain the enzymes lignin peroxidase, manganese peroxidase and lacasse that are important in the degradation process. P. chrysosporium was chosen because of a recent discovery that it contains very little or no lacasse enzyme. We have successfully degraded EE2 completely in 8 days with Lentinula edodes. This process is monitored over time using LC-MS. We are currently working to determine the degradation products and their level of estrogenic activity. Prelimary results of P. chrysosporium with EE2 show that degradation is significantly slower than the drug with Lentinula edodes.

CHED 609

Study of the heterogeneous chemistry of formic acid on mineral dusts by dual chamber transmission FT-IR flow reaction system

Robert M Weingold,, Matthew J Christie, Courtney D Hatch.Department of Chemistry, Hendrix College, CONWAY, Arkansas 72032, United States

Mineral dust aerosol can impact the chemistry and climate of the Earth's atmosphere by providing surfaces for heterogeneous reactions and modifying the radiative balance of the Earth, respectively. Surface/gas reactions can alter the chemical composition of the mineral surfaces, thereby modifying the chemical and radiative properties of the mineral aerosol. To study the heterogeneous chemistry of mineral dust aerosol at atmospherically relevant relative humidities, a transmission Fourier transform infrared (FT-IR) spectrometer equipped with an Aabspec #S reaction chamber in line with an annular denuders has been previously designed, developed and characterized. Studies of formic acid uptake on various dusts and dust analogs will be presented. Gas phase formic acid was extracted in the form of formate from the annular denuders and quantified off line by ion chromatography (IC). Changes in the condensed phase reaction products were monitored using FT-IR spectroscopy and quantified by extraction and analysis by IC. Infrared spectral features are identified and compared to calculated vibration frequencies of formic acid on silica.

CHED 610

Impacts of Aeolian dust on phytoplankton growth rates

McKenzie Keller,, Meredith Miles, Matthew Christie, Courtney D Hatch.Department of Chemistry, Hendrix College, Conway, Arkansas 72032, United States

Phytoplankton of the world's oceans are important chemical regulators and a major food source for many marine species. It has long been hypothesized that iron is the main limiting nutrient for phytoplankton in High-Nutrient Low-Chlorophyll areas. This project examines the impact of Aeolian dust deposition on the growth rates of phytoplankton in both iron-enriched and iron-deficient ocean environments. A correlation has been found between the concentration of Fe-containing montmorillonite clay and growth rates of phytoplankton within iron-deficient environments. The impacts of ocean deposition of atmospherically processed clays have also been studied with respect to their effects on phytoplankton growth rates. Results indicate that the nitrated clay minerals enhance the growth rates of the phytoplankton such that the phytoplankton in iron-deficient environments containing nitrated clays exhibits growth rates similar to that of phytoplankton in iron-enriched environments. This experiment demonstrates the viability of mineral aerosols as a source of nutrients for phytoplankton.

CHED 611

Application of carbon nanotube filters on abandoned mine drainage

Samantha M Shumaker,, Caryl Fish.Chemistry, Saint Vincent College, Latrobe, PA 15650, United States

Acid mine drainage (AMD) is an escalating problem specifically in the Appalachian Region where water tends to contain high levels of metals such as iron and aluminum. In response to the increasingly prevalent issue of AMD, various counteractive options for cleaner waterways have been investigated. One treatment option to explore is using carbon nanotube (CNT) filters to decrease the concentration of metals in these AMD waters. Upon the creation of three different types of filters using double walled CNTs, single walled CNTs, and activated carbon through a suspension-filtering process, AMD waters with different temperatures, iron and aluminum concentrations, and pH values were run through the filters. Samples were analyzed for metal concentrations before and after filtration. The ultimate goal is to find the usefulness of these filters in treatment of AMD.

CHED 612

Passive treatment of abandoned mine drainage and municipal wastewater in a bioreactor using potential biofuel producing microalgae

Jacob M Hendrick,, Caryl Fish.Department of Chemistry, Saint Vincent College, Latrobe, Pennsylvania 15650, United States

Using laboratory-scale bioreactors microalgae, C. vulgaris and C. pyenoldosa, were cultured in BG-11 medium under constant fluorescent light conditions stirring at 100 rpm. The cultures were introduced into a wastewater environment of Abandoned Mine Drainage (AMD) from the Wetlands at St. Vincent College and Municipal Wastewater (MWW) from Unity Township Latrobe, Pennsylvania to determine the contamination treatment ability. Using the EPA method 300.0 the levels of nitrates and phosphates using an Ion Chromatograph and iron levels using a Flame-AA were analyzed before and after a seven-day growth period. The biomass is harvested using vacuum filtration, dried and then weighed. The biomass is crushed to expose oil, washed with a hexane and ether solution and allowed to settle. The hexane solution is evaporated off and mixed with sodium hydroxide in a separatory funnel to produce biodiesel. The percent lipid concentration and biodiesel production is determined for each alga strain.

CHED 613

Comparison between experimental and theoretical adsorption isotherms of CH4 and CO2 on montmorillonite

Michael D Kilmer,, Lorena Tribe.Division of Science, The Pennsylvania State University - Berks Campus, Reading, Pennsylvania 19610, United States

Hydraulic Fracturing for natural gas in the United States requires a special fluid composed of sand, water, and potentially harmful chemicals. Supercritical carbon dioxide may be an alternative, which would avoid the introduction of hazardous materials. Experimental isotherms for methane and carbon dioxide are available in the literature because of the interest in shale gas reservoirs and in carbon sequestration. The synergy of experimental and theoretical data for adsorption processes will provide a molecular level of understanding and comparable determinations of ΔGads. Ultimately, the difference in the ΔGads of both gaseous species will determine if CO2 is able to desorb CH4 from the surface. Computational chemistry is used here to provide a molecular level interpretation of the interactions between CH4 and CO2 and the substrate with Density Functional Theory and the b3lyp/6-311++G(d,p) functional. The models were developed with GaussView, energy minimized with Gaussian 09, and analyzed with Molden.

CHED 614

Determination of a cation/anion balance in a calcareous fen system

Amanda L Gourlay,, Jennifer L Fellin,, Matthew C Rosera, Joseph J Piatt.Department of Chemistry and Biochemistry, Carroll University, Waukesha, Wisconsin 53186, United States

In conjunction with a field calcite precipitation study, fen water samples were collected and analyzed to conduct a cation/anion balance in an effort to understand the geochemical context of the calcite precipitation/dissolution dynamics. Groundwater and surface water geochemistry impact the growth and success of plants in a wetland. The groundwater that feeds this fen is rich in base cations and alkalinity as it is in contact with dolomite, CaMg(CO3)2. Base cations were analyzed using FAA and the major anions were determined titrimetrically and using ion-selective electrodes. Additionally, trace metals that serve as micronutrients were measured using graphite furnace AAS. The geochemical data collected was modeled using MINEQL, a chemical equilibrium model, to determine if the dolomitic geology controls the geochemistry of the wetland stream system.

CHED 615

Phytoremediation of lead contaminated water using aqueous plant extracts

Charne Thomas,, Lovell E Agwaramgbo, Chardai Grays, Tajeve Wright-Young.Chemistry, Dillard University, New Orleans, Louisiana 70122, United States

There is a growing global concern for the environmental and health hazards posed by heavy metal contaminants, especially lead in the soil and ground water. Thus, there is great need to a cheap, efficient, and effective technology to mitigate the growing problem of heavy metal contaminations. The study presented here was undertaken to evaluate the potential of using aqueous extracts of Brassica juncea (Mustard Green), Spinacea oleracea (spinach), Brassica Oleracea (Collard Green), Capsicum Annuum (Red Pepper), Vernonia Amygdalina, Carota Sativus (Carrot), Lycopersicon esculentum (Tomatoes), Vitis vinifera (grapes), and Citrus aurantifolia (lime) for the in-situ remediation of lead contaminated water. After shaking triplicate reaction mixtures of lead contaminated water with each substrate for 22 hours at room temperature, lead removal by the substrates were analyzed using Inductively Coupled Plasma-Atomic Emission Spectrometry. The study concludes that the aqueous extracts of the vegetables and fruits effectively removed lead from contaminated water.

CHED 616

Lead remediation of contaminated water by charcoal, Louisiana red clay, spinach, and mustard green

Shelby L. Edwards,, Tajeve A. Wright-Young,, Lovell Agwaramgbo,, Eric Buckles.Chemistry, Dillard University, New Orleans, Louisiana 70122, United States

Lead is a toxic and naturally occurring substance with documented neurotoxin, toxic, and long-lasting adverse health effects. Lead exposure can cause impaired physical and mental development in children and affects the intestinal tract, kidneys, joints and reproductive system in adults. This study evaluates the removal of 1500 PPM of lead from contaminated aqueous solution using Celite, Louisiana Red Clay, Charcoal, and supernatants from aqueous extracts of Mustard Green (Brassica juncea), and Spinach (Spinacea oleracea). After shaking triplicate reaction mixtures for each substrate for 22 hours at room temperature, lead removal by the five substrates were analyzed using Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). Results suggest that the order of lead removal is Spinach (98%) > Charcoal (96%) > LA Red Clay (88%)> Mustard Green (87%) > Celite (4%). The study concludes that some liquid and solid substrates can efficiently remove lead from contaminated water.

CHED 617

Nutrient level monitoring to determine the water quality of the Ocmulgee River

Kelly Taylor,, Catrena H Lisse.Department of Chemistry, Georgia College and State University, Milledgeville, Georgia 31061, United States

The Ocmulgee River Basin is monitored by an undergraduate research group from Georgia College to determine nutrient levels along the river. It is vital to have clean water for sustaining life, but sources of this clean water are diminishing quickly. The Ocmulgee River parameters are analyzed on factors of nutrient levels, temperature, pH, and turbidity using on-site water testing kits. The testing locations are mapped using Global Positioning Systems technology. EPA guidelines are used to properly bring samples back to the lab and test for results. Water quality trends from data collected from three main rivers in Georgia: Altamaha, Oconee, and Ocmulgee, are highlighted in this presentation.

CHED 618

H2Oconee and beyond: Water quality in the Oconee River basin

Hailee Pekarek,, Catrena H Lisse.Department of Chemistry, Georgia College and State University, Milledgeville, Georgia 31061, United States

A team of undergraduates from the Georgia College Department of Chemistry, Physics and Astronomy have come together to research and monitor the Oconee river basin that spans from north to middle Georgia. The research group is monitoring the nutrient levels, pH and turbidity of the water using on-site water testing kits. Testing is done during the winter months in order to obtain more accurate results and EPA protocols are followed to ensure proper sampling of the surface water. The sampling locations are mapped using Global Positioning Systems to guarantee that future studies are taken at the same locations. This team is investigating the trends between the Oconee, Ocmulgee and Altamaha Rivers that all conjoin in middle Georgia. This presentation summarizes the results and features the techniques used to acquire the results.

CHED 619

Rhodium catalyzed dehalogenation of environmental pollutants

Daniel M Neuburger,, Katherine J Kaiser,, Alicia A Peterson.Department of Chemistry, College of Saint Benedict | Saint John's University, St. Joseph, MN 56374, United States

Halogenated organic compounds are known toxins and ground water pollutants. Toxicity is related to the halogen atoms, so complete dehalogenation of these pollutants effectively removes this concern. Catalytic hydrodehalogenation of chlorinated ethylenes and halobenzenes by 5 wt % rhodium on alumina catalyst in the presence of dihydrogen as the reducing agent under aqueous conditions is described. Kinetic parameters and product distribution for hydrodehalogenation reactions were determined using gas chromatography-mass spectrometry headspace analysis. The effects of various inorganic salts, buffers, and pH on the rate of hydrodecholorination was investigated. Substrate scope was explored using halogenated benzenes where the final hydrodehalogenation products are cyclohexanes.

CHED 620

Analyzing microplastics in a marine environment using FTIR

Madison Martinez,, Charles A Smith.Department of Chemistry, OLLU, San Antonio, Texas 78207, United States

The polluting of the ocean is gradually increasing everyday due to trash being dumped into the ocean. The ocean forms what is called gyres, which are five worldwide giant patches of trash, specifically plastics. Plastic materials are broken down into micro plastics with the help of UV radiation and any physical processes controlled by wind, current, wave, and tide action. The idea of the project was to collect sand from different areas of Corpus Christi, TX beaches and search for microplastics. Once found all plastics were analyzed using the FTIR and calculated for percentages. Percentages were taken in order to find which plastic was most abundant in particular areas of the beaches.

CHED 621

Method development for analyzing chloroethanes in trees over a contamination plume

Lauren Conway,, Charles A Smith.Department of Chemistry, OLLU, San Antonio, Texas 78207, United States

Kelly AFB in San Antonio was established in 1917 and closed in 2001. Kelly operated not only as an airfield, but also a supply and fuel depot, aircraft maintenance and repair facility which included parts cleaning, stripping, painting, and metal fabrication and plating. Over time large amounts of degreasing solvents were disposed of by burying on the site resulting in the current underground contamination plume consisting mostly of chlorinated solvents. The objective of this project is to use SPME to analyze headspace of local tree samples obtained on Kelly AFB existing over the contamination plume in hopes of detecting chloroethanes. To be presented include initial results and optimum methods for analysis including sample collection.

CHED 622

Comparison of methods to EPA 3510c for the detection of several classes of pesticides in water using GC-MS

Scott D Gorman,, Stephen A Waratuke.Chemical Sciences, Bridgewater State University, Bridgewater, Massachusetts 02325, United States

Pesticide use by its very nature has many unintended side effects for both the environment and human beings. Thus, it is necessary to have effective methods of extracting and analyzing compounds present in different matrices including water, soil, or even honeycomb. Since solvents are oftentimes used in extraction and sample preparation, it is important to explore greener methods to limit or eliminate solvent use. We have evaluated alternatives to existing EPA methods for the extraction and concentration of pesticides from water samples and subsequent analysis using Gas Chromatography Mass Spectrometry. The techniques include modifications to the EPA method 3510c Liquid-Liquid Extraction (LLE), the Quick, Easy, Cheap, Effective, Rugged, Safe (QuEChERS) technique, and solid state extraction techniques. The effectiveness of these methods in our studies of different classes of pesticides will be presented.

CHED 623

Measuring halogenated flame retardants by silicone tubing mictroextraction

Megan E. Liggett,, Brian K. Mohney,, Jeffrey D. Weidenhamer.Department of Chemistry/Geology/Physics, Ashland University, Ashland, Ohio 44805, United States

Silicone tubing microextraction was used to extract and concentrate brominated and chlorinated flame retardants from environmental samples. Due to the lipophilic nature of these compounds, silicone tube microextraction is ideal for extracting flame retardants from soil and water. Flame retardants are a category of commercially produced chemicals that have been added to many synthetic products including computers, plastics, and fabrics. These compounds are known to accumulate in the environment, leading to bioaccumulation of compounds in the human body producing potential adverse health effects. Our goal was to develop a method of quantification of flame retardants initially using standards, and to then use this technique to quantify these compounds in environmental samples. This project provides a new analytical approach to understanding the environmental and public health issues resulting from the widespread exposure to these compounds.

CHED 624

Induction of apoptosis by the marine algal toxin Azaspiracid-1

Ahmed K Madhkoor,, Michael Twiner.The Department of Natural Sciences, University Of Michigan-Dearborn, Dearborn, MI 48128, United States

Azaspiracid (AZA) is polyether marine dinoflagellate toxin produced by phytoplankton and accumulates in shellfish. Consumption of contaminated shellfish by humans leads to gastrointestinal illness. As a toxin class, the AZAs have been shown to be highly cytotoxic. The molecular target for AZA has not yet been determined. Our investigations have employed Jurkat T lymphocyte cells to characterize cytotoxicity and the pathway(s) of apoptosis. The mechanisms of apoptosis are highly complex and sophisticated, involving an energy-dependent cascade of molecular events that include the release of cytochrome c from the mitochondria and caspase activation. Cytochrome c is a component required for caspase-3 activation and shown to redistribute from the mitochondria to the cytosol during the early stages of apoptosis. Our investigations have shown that the range of cytochrome c in cells exposed to AZA1 is (2.1 – 5.0 fg/cell) compared to (0.65- 0.71 fg/cell) in control cells.

CHED 625

Comparison of SPME to liquid-liquid extraction for the GC-MS determination of triclosan in water contaminated with OWC's

Robert E Geary,, Stephen Waratuke.Chemical Sciences, Bridgewater State University, Bridgewater, Massachusetts 02325, United States

Organic compounds have been of increasing concern as contaminants in our water systems due to their potential toxicity. Triclosan is commonly used in products such as toothpaste, make-up, and hand sanitizers. Additionally, it could affect the potency of antimicrobial agents. We need to learn more about the presence of Triclosan and related compounds in our environment. The use of Gas Chromatography-Mass Spectrometry is often used for the detection and quantification of organic waste-water contaminants (OWC's) in water. This method first requires an initial sample preparation such as liquid-liquid extraction. We will present our findings comparing the use of Solid Phase Microfilm Extraction (SPME) to EPA method 3510c for the quantification of Triclosan in the absence and presence of other OWC's.

CHED 626

Comparative study of lead removal from lead contaminated water by aqueous extracts of spinach, coffee, and tea

Nichole Lathan,, Lovell Agwaramgbo,, Shelby Edwards.Department of Chemistry, Dillard University, New Orleans, Louisiana 70122, United States

Although few studies have examined the removal of lead from contaminated water using dry biomass of tea leaves and coffee ground, the lead concentration in those studies range from 10-200 PPM of aqueous lead solution. This study compared the effectiveness of aqueous extracts of spinach puree and a variety of brewed coffee and tea in removing lead from 1300 PPM of aqueous lead solution. After 24 hr of agitation at room temperature followed by centrifugation, the lead concentration (in PPM) remaining in the liquid centrifugate from each reaction vessel was analyzed using EPA Method 6010 (Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES)). The results suggest that the order of lead removal was Spinach (99%) > Instant coffee (90%) >Tea (81%). Thus, Spinach extract was more efficient in lead removal from lead contaminated water than coffee or tea.

CHED 627

Preparation of activated carbons from waste peanut shells for use as a sorbent material

Kathleen L Miller,, Ana M Celaya, Jillian L Goldfarb.Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824, United States

Activated peanut shells possess high absorption properties that are applicable across wastewater treatment, specifically for heavy metal and dye removal. We subjected this waste biomass to nitrogen pyrolysis at a temperature range of 550-600°C to produce biochar. BET analysis of raw and pyrolyzed peanut shells of particle size 300-500µm show surface areas of 0.16 m2/g. and 10.23 m2/g, respectively. To increase the surface area and therefore adsorption capacity, we physically activated the pyrolyzed material for 20 minutes in CO2 at a temperature of 400-450°C. Activated peanut shells of particle size 300-500 µm and >600µm have surface areas of 15.28 m2/g and 31.05 m2/g, respectively. With 84% carbon content, the specific surface area of activated biochar of particle size >600 µm is 806.78 m2/g. Further experimentation to determine the optimal activation conditions are underway.

CHED 628


CHED 629

Assessing estrogenic and androgenic activity of UV filter photoproducts

Samuel C Jensen1,, Kristine H Wammer1, Laura A MacManus-Spencer2, Dalma Martinovic-Weigelt3.  (1) Department of Chemistry, University of St. Thomas, St. Paul, MN 55105, United States  (2) Department of Chemistry, Union College, Schenectady, NY 12308, United States  (3) Department of Biology, University of St. Thomas, St. Paul, MN 55105, United States

Previous research suggests that some UV filters commonly used as active ingredients in sunscreens may exhibit estrogenic or androgenic activity and produce photoproducts that are also potential endocrine disruptors. Here, UV filters were exposed to simulated sunlight to generate photoproduct mixtures and characterized by HPLC and LC-MS. Mixtures were screened for endocrine activity using two transcriptional assays. The endocrine activities of the samples were interpolated by a least-squares means procedure from a nonlinear sigmoidal dose response curve fit to the relative luminescence units of the estradiol/testosterone standards. Octyl methoxycinnamate (octinoxate) and a mixture of its photoproducts exhibited androgenic activity in vitro;one active photoproduct (4-methoxybenzaldehyde) has been identified. Octyl dimethyl para-aminobenzoic acid (padimate O) had no androgenic activity in vitro, whereas a mixture of its photoproducts was found to have activity. Utilizing flash chromatography, present work is focused on isolating and identifying the active photoproduct(s).

CHED 630

Characterizing the particulate phase of mainstream hookah smoke

Jessica Annonio1,, Jeff Baker2, Cindy DeForest Hauser1, Timothy Oh1.  (1) Department of Chemistry, Davidson College, Davidson, North Carolina 28035, United States  (2) TSI, Inc., St. Paul, Minnesota, United States

Hookah (also known as narghile, shisha, and hubble-bubble) is a form of tobacco use originating in India during the 15thcentury and has spread to various Middle Eastern and Mediterranean regions and Western countries. Tobacco treated with ma'ssel, a sweet tasting paste, is placed in the head of the hookah and heated with charcoal. As the user inhales, hot air vaporizes the tobacco, and semivolatile components condense to form smoke. The smoke is bubbled through liquid contained in the bowl and inhaled.

Other forms of tobacco use such as cigarettes and chewing tobacco have been well characterized; however, information regarding hookah is still lacking. In this study, particle concentrations and size distributions of mainstream hookah smoke particulate matter are quantified. Additionally, the effect of filtration media, inhalation time intervals and heat source are investigated. By looking at these parameters, the adverse health effects of hookah can be better understood.

CHED 631

Bacterial resistance to four classes of antibiotics in the Minnesota River

Marianna E Moffatt1,, Elizabeth W Beck1, Tucker R Burch2, Timothy M LaPara2, Kristine H Wammer1.  (1) Department of Chemistry, University of St. Thomas, St. Paul, MN 55105, United States  (2) Department of Civil Engineering, University of Minnesota, Minneapolis, MN 55455, United States

There is increasing evidence that environmental bacteria are an important reservoir of antibiotic resistance due to antibiotic use in both human medicine and agriculture. This project is part of a larger study investigating impacts of agricultural runoff and wastewater treatment plants on bacterial resistance in surface waters to four classes of antibiotics: tetracyclines, macrolides, sulfonamides, and fluoroquinolones. Here, antibiotic resistance genes (ARGs) were quantified among bacterial communities collected from ten sites during nine sampling events between Summer 2011 and Summer 2012. Five ARGs, the 16S rRNA gene, and intI1 were quantified using qPCR. Other components of the study include measuring antibiotic concentrations and resistance levels among cultivable bacteria from the same sites. To date, our findings suggest there are no consistent differences among sites in relative levels of cultivable resistant bacteria. However, there are higher quantities of antibiotics and ARGs found in samples directly impacted by wastewater treatment plants.

CHED 632

Industrial and agricultural pollutants in the Susquehanna watershed of Pennsylvania

Michelle Piotrowski,, Megan Forman,, Catherine Blithe, Amy Dougher, Christopher Millet, Michael Montemarano, J. Scott Niezgoda, Usha Rao.Department of Chemistry, Saint Joseph's University, Philadelphia, PA 19131, United States

Concentrations of metals and nutrients in the Susquehanna River watershed, an EPA-designated “American Heritage River” system, have been analyzed seasonally over several years. The Susquehanna River and its tributaries form 50% of the inflow of the Chesapeake Bay, and comprise its largest source of industrial and agricultural pollution. In particular, over a century of anthracite coal mining in Northeastern Pennsylvania has contributed acidity, turbidity, and metals to the Susquehanna basin. In addition, since the Susquehanna River drains some of the most agriculturally productive land in the U.S., nitrogen and phosphorus from agricultural runoff enter the river system and are carried downstream to the ecologically vulnerable Chesapeake Bay.

The current study assesses field parameters such as pH, temperature, conductivity, and temperature in the water, as well as nutrient levels in water and concentrations of iron, calcium, copper, zinc and nickel in the water and sediment collected from 18 sample sites in Pennsylvania. In general, nickel, zinc and copper were present in low concentrations in water and sediment, while calcium was elevated in the aqueous phase and iron in the sedimentary phase. Phosphorus levels are relatively low (<0.1 mg/L) in the samples collected. However, given the large volume of water that reaches the Chesapeake Bay from the Susquehanna River and its tributaries, total phosphorus loads from the Susquehanna River system tend to contribute to eutrophication in the Chesapeake Bay.

CHED 633

Collection and analysis of volatile organic compounds from a hair salon in Eastern Oregon

Garret Zinzer,, Jason Mumm, Robert Barrington, Philip Deenik, Jeremy Riggle.Department of Chemistry & Biochemistry, Eastern Oregon University, La Grande, OR 97850, United States

Passive sampling semi-permeable membrane devices (SPMDs) were used to collect air samples from a hair salon in Eastern Oregon. SPMDs were deployed for just over 30 days in a local boutique. Following deployment, the SPMDs were retrieved and returned to the laboratory. SPMDs were then dialyzed with hexane to remove volatile organic compounds (VOCs). The dialysate was then reduced in volume and analyzed. Identification and quantification of VOCs was carried out using gas chromatography-mass spectrometry (GC-MS).

CHED 634

Chemical characterization of PM10 in the Grande Ronde Valley in Eastern Oregon

Philip Deenik,, Jason Mumm, Robert Barrington, Garrett Zinzer, Jeremy Riggle.Department of Chemistry & Biochemistry, Eastern Oregon University, La Grande, OR 97850, United States

Atmospheric particulate matter smaller than 10μm in aerodynamic diameter (PM10) is a complex mixture of organic and inorganic components. These components are largely a product of local processes and also have significant implications for human health. This research project focuses on the PM10 in the Grande Ronde Valley, Oregon. Samples were collected on quartz-fiber filters using a hi-volume sampler on the campus of Eastern Oregon University. These samples were then analyzed for different metals using Atomic Absorption Spectroscopy. The samples were also tested for polyatomic ions using High Performance Liquid Chromatography. Volatile Organic Compounds (VOC's) and Polyaromatic Hydrocarbons (PAH's) were also extracted and quantified using Gas Chromatography Mass Spectrometry (GC-MS).

CHED 635

Characterization of ozonation products for the macrolide antibiotic roxithromycin

Wendy J Consoer,, Daniel J Kellen, James R Byrnes, Kristine H Wammer.Department of Chemistry, University of St. Thomas, St. Paul, MN 55105, United States

With the increase of antibiotics detected in surface water, it is important to understand whether or not antibacterial activity is retained when antibiotics are transformed during the drinking water treatment process. This study examines the effects of ozonation on the macrolide roxithromycin. Previous studies have suggested that some ozonation products of roxithromycin may retain antibacterial activity because parts of the molecule necessary for activity are left intact. This study aims to identify the major ozonation products of roxithromycin and determine the presence of any antibacterial activity. Roxithromycin solutions were treated with aqueous ozone, under various pH and DOC conditions, and residual roxithromycin was quantified using HPLC analysis. Product mixtures were screened for antibacterial activity with a biological assay using Staphylococcus epidermidis then analyzed using QTOF-MS. To date no ozonation products that retain antibacterial activity have been observed.

CHED 636

Chemical sustainability in the bromination of organic compounds: Evaluating a tungstate catalyst in the synthesis of 3-bromooxindole-3-acetic acid, a potential therapeutic agent

Kyle E. Murphy,, Edward J. Brush.Department of Chemistry, Bridgewater State University, Bridgewater, MA 02325, United States

The goal of green chemistry is to eliminate the use and generation of hazardous chemicals to prevent harm to people and the environment. We have been studying the synthesis of 3-bromooxindole-3-acetic acid (BOAA). BOAA is converted into 3-methyleneoxindole (MOI) which is an inhibitor of cysteine proteases, enzymes that are suspected contributors in diseases such as cancer. The major issues with the BOAA synthesis are poor atom economy and low percent yield. The standard synthesis requires indole-3-acetic acid (IAA), tert-butanol, and N-bromosuccinimide (NBS). We have identified that the bromination of IAA by NBS is responsible for the poor efficiency of this reaction, and have evaluated bromide salts, hydrogen peroxide, and a layered double hydroxide tungstate catalyst for the greener bromination of IAA. Initial testing of this catalyst has given promising results for a more efficient BOAA synthesis.

CHED 637

Quantitative analysis of heavy metal contaminants in river sediments using LIBS

Chris Malfitano,, Jude A. Kelley.Department of Chemistry, College of the Holy Cross, Worcester, Massachusetts 01610, United States

We have developed a new technique for analyzing river sediment for heavy metal contamination. Atomic Absorption Spectroscopy (AA) is the gold standard for such quantification, but has issues with sample preparation, waste generation and speed. We report a laser induced breakdown spectroscopy (LIBS) approach as a quicker and cheaper alternative. We have demonstrated that the technique is both sensitive and repeatable enough for use in environmental monitoring.

LIBS is commonly used for qualitative analysis. For quantitative analysis, the setup must be optimized for reproducibility. The sample rests on a platform that can be reproducibly vertically positioned to overlap with the focal point of the laser. A standoff lens collects the light emitted from the generated plasma, enabling operation at low laser power, which minimally disturbs the samples.

We benchmark the LIBS results with AA measurements performed on identically contaminated samples.

CHED 638

Bioavailability of cadmium in inexpensive jewelry

Mallorie L. Boron,, Jeffrey D. Weidenhamer.Department of Chemistry, Geology & Physics, Ashland University, Ashland, Ohio 44805, United States

The US Consumer Product Safety Commission (CPSC) recently accepted methods proposed by industry for testing cadmium bioavailability in children's jewelry. Samples are extracted in saline solution (simulating mouthing) or 0.07 M hydrochloric acid (simulating swallowing) to estimate cadmium release. One unanswered question is whether cadmium release increases when electroplated coatings are damaged. Earlier tests identified several pieces for which leaching increased as much as ten-fold when the item's coating was damaged. For this study, X-ray fluorescence (XRF) was used to identify high-cadmium items with a range of zinc content, because zinc appears to reduce cadmium bioavailability. Duplicate high-cadmium samples, one cut in half and one left intact, were analyzed by the different extraction methods. An alternate procedure using a briefer extraction of ground material from each jewelry item is being compared to the other test methods. Following bioavailability testing, total cadmium and zinc content of all items is being determined.

CHED 639

Photoproduction of singlet oxygen in natural waters: Influence of Cu2+ and Fe3+ complexed by dissolved organic matter

W. Jedida Ouedraogo,, John D. Thoemke.Department of Chemistry and Geology, Minnesota State University, Mankato, Mankato, MN 56001, United States

Dissolved organic matter (DOM) in natural waters is an assemblage of biological macromolecular fragments and has a number of ecological and geochemical functions, including metal binding. The metal ions interact with DOM to form complexes, and this interaction influences the photoproduction of singlet O2, which plays a significant role in chemical transformations within the water column. This project investigated the influence of DOM-bound metal ions on the photoproduction of singlet O2.

Natural water samples were obtained, filtered, and titrated with Cu(NO3)2, and Fe(NO3)3. The samples were irradiated with ultraviolet light. Then the depletion of furfuryl alcohol (FFA), which is proportional to the amount of singlet O2, was monitored by HPLC analysis. This was compared to the photoproduction of singlet O2 in each sample in the absence of added metal ions. As expected, variations in singlet O2 production were observed.

CHED 640

Lake Macatawa sediment analysis

Eric Greve,, Dan Tobert, Julissa Pabon, Graham Peaslee.Department of Chemistry, Hope College, Holland, MI 49422, United States

An EPA-funded toxicological study of Lake Macatawa sediment was performed jointly by Hope College and Grand Valley State University in 2003-2004. Fourteen of the fifteen sites studied showed no macroinvertebrate toxicity and were well within EPA acceptable limits for both organics and heavy metals. However, one site showed elevated levels of lead and polycyclic aromatic hydrocarbons (PAHs) – both above the EPA probable effect limits. This initially indicated a leaking underground gasoline storage tank or just a long history of fuel spills. An extensive study in 2005-2006 by Dan Tobert and Julissa Pabon at Hope College further examined the geographical extent of the lead and PAH sediment contamination. Now six years later, the same location was revisited to determine if the PAH and lead contamination has grown, decreased, or remained the same. A modified EPA solid-liquid extraction procedure for PAHs was employed and a Gas Chromatograph/Mass Spectrometer was used to identify and quantify PAHs extracted from sediment samples. Microwave assisted acid digestions and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) was used to determine lead and other heavy metal concentrations in the sediment samples. By comparing these results to the data collected six years earlier along with the ratio between various PAHs, it was possible to identify the source of pollutants to be pyrogenic and not petrogenic in origin.

CHED 641

Heavy metal remediation using tea waste: A comparative study

Yshua Rodriguez,, Nixon Mwebi.Physical and Earth Sciences, Jacksonville State University, Jacksonville, AL 36265, United States

Heavy metal remediation is a global endeavor due to the numerous hazards caused by the toxicity of the heavy metals in the environment. Increased industrialization has lead to a widespread use of heavy metals resulting in contamination of waters by these toxic metals from the industrial discharge. The toxicity of heavy metals has not only been linked to increased damage of organs such as the kidney or liver but also to the promotion of neurodegenerative disorders and cancer. This has made the removal of the heavy metals and their immobilization a global environmental concern.

The uptake of heavy metals by various natural substances has found increased use. The use of tea waste from domestic and factory sites for heavy metal adsorption or remediation use has gained popularity in recent past. This is partly due to the fact that use of tea waste not only helps remediate the toxic waste it also puts into use the increasing amounts of the waste biomaterial. In this study, the ability of tea waste from local restaurants and vendors to uptake heavy metals such as lead, chromium and cadmium was investigated using both the batch and column experimental setups. Our findings indicate that the ability of the tea waste to adsorb the heavy metals depended on both the type and concentration of the heavy metal. This effect was evident in both the batch and column studies but was more evident in the latter experiments.

CHED 642

Investigation of pharmaceutical pollution of surface water in Georgia

Nathan Potter,, Catrena Lisse.Department of physics, Chemistry, and Astronomy, Georgia College and State University, Milledgeville, Georgia 31061, United States

A collaborative group of chemistry and environmental science undergraduate students at Georgia College and State University is investigating the presence of pharmaceuticals in local water. Xenoestrogens are synthetic compounds that mimic the hormone estrogen when introduced to the human body. These compounds can be present in human waste after the consumption of pharmaceuticals, which leads to the contamination of sewage. Although the sewage is treated by a sewage treatment plant there is little to no treatments for xenoestrogens leaving the compounds nearly untouched. Once the sewage treatment water is released the xenoestrogens may contaminate surface water areas such as lakes and rivers. This project focuses on testing various surface water areas in middle Georgia for xenoestrogens due to human waste and comparing the results with EPA standards. The presentation summarizes the methods and results of the collaborative group findings.

CHED 643


CHED 644

Degradation of the antidepressant venlafaxine in aerobic municipal wastewater sludge

Cody Staebler1,, Stephanie S Strand2, Melissa M Schultz1.  (1) Department of Chemistry, The College of Wooster, Wooster, Wooster 44691, United States  (2) Department of Biology, The College of Wooster, Wooster, OH 44691, United States

Public and regulatory interest regarding the presence of pharmaceuticals and personal care products (PPCPs) in the environment is increasing. Wastewater treatment is the primary route of PPCPs into the environment. Within wastewater treatment there are many routes by which chemicals are transformed; however, biodegradation due to the metabolic activities of microorganisms during the treatment process is the predominant route of PPCP breakdown. Consequently, it may be possible to decrease the amount of PPCPs entering the environment by augmenting WWTPs with microbes capable of more efficiently degrading these molecules. To establish a model system for exploring the biodegradation of PPCPs, initial studies investigated the degradation of the widely prescribed antidepressant venlafaxine. Microcosms containing aerobic sludge were spiked with deuterated venlafaxine.Two venlafaxine metabolites were observed as early as day 2 of the microcosm experiment. Bacterial community composition shifts in the sludge will be determined by DGGE (Denaturing Gradient Gel Electrophoresis).

CHED 645

Comparison study of volatile components extracted from Rhizophora mangle L. bark, leaves and roots in Biscayne Bay, Florida

Kristel Sanchez,, Patricia Altagracia Santana,, Kyle Wicomb, Naomi Pierre, Joyce Louis, Mayra Exposito.Chemistry, Florida International University, Biscayne Bay Campus, North Miami, Florida 33181, United States

Essential oils were extracted from different parts of Rhizophora mangle L. to compare the different compositions of their volatile components. Isolation and characterization of these chemicals was performed by steam distillation, gas chromatography and Infrared Spectroscopy. Kinetic analysis was performed using UV-Vis spectrophotometer with emphasis on the bark extractions due to their biochemical properties. Extractions were performed on each of the parts selected for this study with solvents with different polarities. Preliminary findings on the characterization of the chemical components across the different parts of Rhizophora mangle L. showed varying levels of composition, with manool being present at a high percentage in the bark extracts. Manool's oxidation reaction was studied using ceric ammonium nitrate reagent. We hypothesize that this oxidation reaction is of great biomedical importance for human welfare; previous research has shown that manool and its derivatives have inhibitory properties that could be beneficial for human health.

CHED 646

Brazilian pepper: An invasive tree in the South Florida Everglades with beneficial properties for human health

Shantell Rolle,, Patricia Santana,, Gabriela Tarnay, Mayra Exposito, Maria Cristina Del Sol, Nashua Wisdom.Arts and Sciences, Florida International University, Biscayne Bay Campus, North Miami, Florida 33181, United States

The ornamental plant Brazilian pepper invades aquatic and terrestrial habitats, reducing the quality of native South Florida biotic communities. The isolation and characterization of the essentials oils from the fruits, leaves and bark was done to study the nature of their properties and actions. Following the extraction by simple steam distillation, the oils were isolated using a “Green Technique” based on the freezing points of the substances. Characterization of the major components involved GC, Infrared, and Refractive Index. Targets molecules were modeled using SPARTAN Software calculating its electronic and molecular properties. Chemical differences were found in the essential oils of the seeds, leaves and bark. Brazilian pepper is known worldwide for its diverse ethnobotanical properties, such as wound healing, larvae control for the Aedes aegiptis mosquito, and antioxidant properties. Future research may prove that utilizing this abundant invasive species as a resource could benefit both human health and the environment.

CHED 647

Quantitative study of the effect of humic acids on spectrophotometric analysis of Hg(II) using dithizone

Zachary Andreasen1,, Hong Zhang1, Stephen Okine1, Baohua Gu2.  (1) Department of Chemistry, Tennessee Technological University, Cookeville, TN 38501, United States  (2) Environmental Science Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States

Our previous research showed that humic substances may affect spectrophotometric analysis of environmental samples of Hg(II) using dithizone, which has thio-groups of high affinity for Hg(II). We did a follow-up study to quantify this effect using Acros humic acid (ACHA) and Aldrich humic acid (ADHA) and model organic acids (oxalate and cysteine). Our study shows that both ACHA and ADHA can decrease the sensitivity of the Hg(II) analysis (Hg(II) calibration curve slopes) linearly within 20-80 ppm of the HAs, but at 100 ppm, ADHA causes more decrease than ACHA. Oxalate shows a very mild effect over 20-100 ppm. Cysteine shows no effect below 1 ppm, but significantly decreases the Hg(II) calibration curve slopes linearly at 1-3 ppm and completely inhibits binding of dithizone to Hg(II) above 3 ppm. These results further indicate that the thio-groups in the HAs are responsible for the effect of the HAs on the Hg(II) analysis.

CHED 648


CHED 649

Optimization of expression of nitrobenzene dioxygenase reductase

Austin Laroche,, Matthew Neibergall.Department of Chemistry, Bethel University, St. Paul, MN 55112, United States

Nitroaromatic compounds are commonly used in pesticides, dyes, and explosive. When disposed of improperly, these compounds can be released into the environment acting as mutagens and pollutants. This is especially harmful because the stability of the benzene ring allows the nitroaromatic compound to resist oxidation. The bacteria Comamonas has proven capable of catalytically degrading nitrobenzene to catechol through the use of a multicomponent nitrobenzene dioxygenase (NBDO). Past research has successfully cloned NBDO genes into an E. coli vector which allows for more efficient cellular growth and protein expression. The purpose of this work is to seek to optimize conditions for growth of E. coli with our NBDO cloning vector present and to maximize the expression and isolation of nitrobenzene dioxygenase reductase (NBDR). This will be an important step in determining the overall reaction mechanism of the Rieske dioxygenase enzyme found in Comamonas. Some variables that will be tested are time of bacterial growth, medium formulation, temperature, and IPTG concentrations.

CHED 650

Re(VII) reduction in the presence of sorbed Fe(II): Plausible removal pathway in suboxic porewaters

Clayton T Wagner,, Paul J Yanez, Megan M Maloney, Trent P Vorlicek.Department of Chemistry and Geology, Minnesota State University, Mankato, MN 56001, United States

Re deposition is generally thought to involve reduction. Unfortunately, the pathway to Re removal remains unclear. Authors purport Re sequestration begins in suboxic (absence of oxygen and sulfide) environments; others produce evidence supporting removal under anoxic (presence of sulfide) conditions. This research aims to clarify such issues by positing a plausible pathway to Re fixation in suboxic sediments. While reduction of Tc(VII) is known to be strongly favored in the presence of alumina-sorbed Fe(II), analogous behavior for Re(VII) has not been established. Preliminary glovebox experiments involve reacting 10 μM ReO4- at pH=7.0 in the presence of 100 μM Fe(II), hydrated δ-alumina, or hydrated δ-alumina previously exposed to 100 μM Fe(II). At various times, aliquots of test solutions are filtered (0.45 μm) and ReO4- quantified using reverse phase ion pair chromatography with suppressed conductivity detection. For comparison, similar experiments involving Mo(VI) (MoO42-) will also be performed and presented.

CHED 651

Ion exchange chromatography techniques for determination of rare earth elements in ultramafic rocks

Matthew H. Pittman,, Scott Vetter.Chemistry, Centenary College of Louisiana, Shreveport, Louisiana 71104, United States

The abundance and elemental ratios of the rare earth elements (REE) are used as indicators of the petrogenesis of rocks. Typical basaltic rocks have REEs in ppm abundances. Ultramafic igneous rocks have extremely low concentrations of the REE at or near the detection limit of the ICP-MS. Ion-exchange columns have been used to remove unwanted elements thereby concentrating REEs so they can be detected by the ICP-MS without additional dilution. Exchange columns consisted of a 30 mL beaker with a conical bottom that was welded to 30 cm long, quarter-inch diameter Teflon tubing. Twenty-one cm of 50Wx8 cation exchange resin (200-400 mesh) was placed in the columns for all extractions. Samples were dissolved in HNO3 and HF, dried; redissolved in HCl, and loaded into the column. The first 70 mL of eluent gave >99% of the REEs were captured off the column.

CHED 652

Fluorescence characterization of chromophoric dissolved organic matter produced by bacteria in the North Atlantic Subtropical Gyre

Thomas Kinsey1,2,, Natasha McDonald2, Rachel Parsons3.  (1) Undergraduate Department of Chemistry, Spring Hill College, Mobile, Alabama 36608, United States  (2) Bermuda Bio-Optics Project, Bermuda Institute of Ocean Science, Ferry Reach, St. George's GE01, Bermuda  (3) Molecular Marine Biology, Bermuda Institute of Ocean Science, Ferry Reach, St. George's GE01, Bermuda

The chromophoric fraction of dissolved organic matter (CDOM) is a major component in the regulation of the oceanic underwater light field, affecting the amount of solar radiation available throughout the water column for primary producers, and creating developmental issues for remote sensing of water color as a proxy for phytoplankton abundance. One challenge in characterizing the global CDOM pool has been identifying individual chromophores and the manner in which CDOM composition changes, based on spatial and temporal variability. Evidence has suggested that a large fraction of the CDOM pool is derived from terrestrial matter; however, microbial production of CDOM has also been demonstrated. Here we pose the question of whether these various sources of CDOM differ in chromophoric composition. The CDOM absorption spectrum allows for a quantitative measurement of CDOM concentration, but tells little about the individual molecules making up the oceanic CDOM pool. However, fluorescent characteristics of CDOM can provide more insight into identifying molecules or groups of molecules within this CDOM pool. In this experiment, water from the Bermuda Atlantic Time Series site in the North Atlantic Subtropical Gyre was incubated to allow bacterial production of CDOM. Samples were taken at various time points throughout the incubation and analyzed via spectroscopic methods including UV/VIS absorbance and 3D excitation/emission matrix spectroscopy (EEMS) to investigate CDOM abundance and to characterize fluorescence of individual chromophores within the CDOM sample. These measurements were taken in conjunction with total bacterial abundance and dissolved organic carbon (DOC) measurements to correlate with CDOM production.

CHED 653

Multidimensional fractionation and mass spectral characterization of Suwannee River fulvic acid

Codey B Henderson,, Alexandra C. Stenson.Chemistry, University of South Alabama, Mobile, Alabama 36688, United States

Previously, we separated aqueous humic substances through a phenyl reversed-phase chromatography column into 100 fractions, which were then analyzed through mass spectrometry (including tandem mass spectrometry and H/D exchange). The data revealed early eluting material is highly oxidized; late eluting material retains more characteristics of precursor molecules. Here, further fractionation of early, mid, and late eluting fractions through a Sielc Obelisc column in tandem with two Ni2+ IMAP columns (stripped then un-stripped) will be performed. Previously noted contamination from non-humic peaks will be addressed by increasing the amount re-fractionated through the second stage and identifying non-humic contaminants and their source. Once the additional fractionation has been optimized, fraction will be analyzed through mass spectrometry to further elucidate compositional differences. The elucidation is an important step forward in the structural characterization of humic substances and the ability to use, reproduce, or manipulate humic substances to environmental, chemical, or pharmacological benefit.

CHED 654

Microbial diversity of the deep subsurface: Characterization and identification of thermophiles

KaNesha Gillyard1,2,, Abidemi Ojo2, Esta van Heerden2.  (1) Department of Chemistry, Spelman College, Atlanta, GA 30314, United States  (2) Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, Bloemfontein, South Africa

Previous phylogenetic studies have shown high abundance of thermophiles in extreme environments. In addition, 16S ribosomal RNA libraries have confirmed the presence of the thermophiles in the South African deep mines. Culture-dependent and culture-independent methods were used to analyze the microbial diversity of the deep mine community. Therefore, we attempted to characterize and identify thermophiles from the soil and to conduct biodiversity studies of fissure water collected from the deep mine using culture-dependent and culture-independent techniques, respectively. Isolation relied heavily on bacteria cultivated in rich media and identification of the pure isolates using a molecular approach. Preliminary results obtained suggest a diversified bacterial environment in the soil with the presence of both Gram positive and Gram negative bacteria. Furthermore, the microbial biodiversity studies of the fissure water sample solely based on denaturing gradient gel electrophoresis method suggests the presence of eukarya and bacteria, and possibility of the absence of archaea. As thermophiles have been known to demonstrate great importance in revolutionary global technology, the isolation and identification of thermophiles conducted in this study may be relevant to future revolutionary publications.

CHED 655

Speciation, photophysical, and chiroptical properties of europium(III)-tetracycline species

Kirandeep K. Deol,, Gilles Muller.Department of Chemistry, San Jose State University, San Jose, CA 95192-0101, United States

Tetracycline (TC) is a commonly used antibiotic that prevents the growth and spread of bacterial infections and treats acne. The biological action of TC is known to inhibit protein synthesis in bacteria; however, the chemical behavior of TC is not completely understood. Studies have shown that TC can exist in various species and conformations depending on the environment present. TC speciation depends on the effects pH, metal ions, and solvents have, so our goal in this research project will be to understand how these effects affect the structure, species, photophysical and chiral-optical properties of TC.

A complete study of the species formed and its conformation in relation to the metal ion, solvent, and pH was envisaged using steady-state luminescence, time-resolved luminescence, and 5D07F0(Europium, or Eu) excitation spectroscopy. In addition to this study, we applied the circularly polarized luminescence (CPL) measurement to understand how the conformational speciation of tetracycline reflects the chiral structural changes with the emitting lanthanide metal, Eu(III).

These various measurements confirmed the presence of three different TC species in solution, TC (pKa1 = 3-4), TC- (pKa2 = 7.3-8.1), TC2- (pKa3 = 8.8-9.8). Each TC species has the capability of forming a unique complex with the Eu (III) metal ion, which was determined through the use of CPL. We have shown that the change in pH of each solution favors the formation of certain TC species that act as a “fingerprint” to indicate the structural changes to the chiral-optical properties of each Eu (III) – TC species.

CHED 656

Investigation of the photophysical and chiroptical properties of Eu(III), Tb(III), and Gd(III) complexes with a derivative of dipicolinic acid

Jacob M. Schekman,, Joey Nguyen, Gilles Muller.Department of Chemistry, San Jose State University, San Jose, CA 95192-0101, United States

Lanthanide metals, once thought of as rare material, have become an increasing interest in Inorganic Chemistry. From catalyzing petroleum to intensifying stadium lighting, or in the case of this project, identifying the chirality of surrounding molecules in a solution, lanthanides have become a widely used material.
We hypothesize that our ligand of interest, a derivative of dipicolinic acid, will result in the formation of triple-helical complexes and lead to stable chiral emitting species on the luminescence time scale. We also hypothesize that if the intermolecular interactions between a chiral molecule and the lanthanide(III) complex are stronger for one enantiomer than another, then there should be a measurable shift in the racemic equilibrium of the complex using the circularly polarized luminescence (CPL) spectroscopy where the difference in the emission of left and right circularly polarized light is monitored. We also resorted to the 5D0¬7F0(Eu) excitation spectroscopy to study the speciation of the Eu(III):ligand complex solution, and steady-state and time-resolved luminescence measurements were conducted to determine the efficiency of the energy transfer from the ligand to the lanthanide(III) ions.

These various measurements confirmed an efficient ligand-lanthanide(III) energy transfer, but a weak metal-centered luminescent quantum yield due to an incomplete intersystem-crossing-transfer. It has also been found that aromatic p-stacking and hydrogen bonding interactions are the main contributors to effective perturbation of our racemic D3 Eu(III) complex. This work confirmed that our lanthanide(III) complexes, with the use of CPL, can be employed to determine the molecular structure of various chiral luminescent species.

CHED 657

Synthesis of novel magnetic anisotropic single-molecule magnets

Jacob C Lutter,, Curtis M Zaleski.Department of Chemistry, Shippensburg University, Shippensburg, PA 17257, United States

In order for a material to function as a single-molecule magnet (SMM) it must be able to remain in a particular spin state, which is only possible if there is an energy barrier between the up and down states. The energy barrier is related to the temperature at which the magnet can operate and store data. For a SMM the energy barrier is equal to |D| x S2, where D is the magnetoanisotropy and S is the spin state. Thus, the goal of SMM research is to produce an energy barrier of sufficient height that the molecule is able to store information at room temperature. The goal of the proposed research is to design a molecule that possesses a large spin value but is also asymmetric. The metals to be explored include manganese, iron, cobalt, and chromium.

CHED 658

Structure and characterization of a manganese 15-MC-5

Benjamin R Tigyer1,, Matthias Zeller2, Curtis M Zaleski1.  (1) Department of Chemistry, Shippensburg University, Shippensburg, PA 17257, United States  (2) Department of Chemistry, Youngstown State University, Youngstown, OH 44555-3663, United States

Metallacrowns are a class of coordination compounds that are inorganic analogs to crown ethers. While a crown ether possesses the repeat unit of carbon-carbon-oxygen, a metallacrown possesses the repeat unit of metal-nitrogen-oxygen. Most metallacrowns can encapsulate metal ions within the cavity made by the [M-N-O] ring. In an attempt to synthesize novel metallacrowns, the metallacrown MnII(Fm)2[15-MCMn(III)N(shi)-5](Im)5 [where shi3- = salicylhydroximate, Fm = formate, and Im = imidazole] was synthesized and characterized by X-ray diffraction and infrared spectroscopy. The compound crystallized in the monoclinic space group P 21/c with a = 13.2053(12) angstroms, b= 24.621(2) angstroms, c= 21.491(2) angstroms, alpha= 90 degrees, beta= 101.8610(10) degrees, gamma= 90 degrees, V=6838.0(11) angstroms3, and Z= 4. In addition, the imidazole molecules and carboxylate groups will be substituted with other derivatives that will hopefully be added to the MnII(X)2[15-MCMn(III)N(shi)-5] molecule, where X = carboxylate anion.

CHED 659

Synthesis and spectroscopy of 15N-labeled bis(trispyrazolylborate)cobalt(II)

Jami R Bennett1,, Tyler S Hageman2, David L Tierney1, Robert M McCarrick1.  (1) Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States  (2) Department of Chemistry, MidAmerica Nazarene University, Olathe, KS, United States

The 15N-labeled congener of bis(trispyrazolylborate)Co(II) was prepared using 15N-pyrazole that was synthesized from 15N-hydrazine sulfate and tetramethoxypropane. Pulsed EPR (ENDOR and ESEEM) of both the natural abundance (14N) and isotopically labeled (15N) compounds will be presented. These are among the first successful pulsed EPR studies of a high-spin Co(II) complex, and the data provide a clear path toward understanding the nature of bonding in this historically important complex.

CHED 660

Carbonic anhydrase as a model for matrix metalloproteinase inhibition

Tessa M. Woodruff,, Amy R. Marts, Anthony A. Forchione, Justin M. Chu, David L. Tierney.Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States

Carbonic anhydrase (CA) is being used to model matrix metallproteinases (MMPs), as both are zinc-dependent enzymes that bind to zinc in a His3(OH) environment. CA is being used to screen potential zinc chelators, such as maltol, thiomaltol, acetohydroxamate and benzylacetohydroxamate, via spectroscopic examination of their binding to Zn-CA and cobalt substituted CA, using optical spectroscopy. More detailed spectroscopy of the Zn- and Co-containing enzymes is being used to examine their binding modes.

CHED 661

Synthesis and purification of H2TPP and its metal complexes analyzed through NMR and fluorescence spectroscopy

Brianna A Hill,, Ronald Strange.Department of Chemistry, Fairleigh Dickinson Univeristy, Madison, New Jersey 07940, United States

We have investigated the optical fluorescence and absorption properties of several tetraphenylporphine (TPP) bases and their metal complexs. The fluorescence spectra are reported. The kinetics of metal insertion into the TPP base was studied by fluorescence and by NMR. In addition, the synthesis of several TPP derivatives under mild conditions were carried out using a deutero acid to establish the source of protons in the adduct.

CHED 662

Synthesis of a platinum(II) dithiolene building block with labile diimmine ligands

Jacob B. Smith,, Paul J. Derry, Bradley W. Smucker.Department of Chemistry, Austin College, Sherman, Tx 75090, United States

In our quest to synthesize and characterize light-harvesting building-blocks utilizing diimmine platinum(II) dithiolene complexes, we report the synthesis and characterization of cis-(pz)2Pt(mnt) (mnt = maleonitriledithiolate, pz = pyrazine).This building-block exhibits light-absorbing and redox properties as well as possessing relatively labile monotopic pyrazine ligands. The exchange of pyrazine with a variety of bridging immine ligands is utilized in the syntheses of new building-blocks with greater stability and more desirable redox and light-harvesting properties for use in the self-assembly of supramolecular squares and model complexes.

CHED 663

Magnetic susceptibility of iron and cobalt spin crossover compounds in solution

Daniel P. Baker,, Amy R. Marts, David L. Tierney.Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, United States

Spin crossover (SCO) complexes are of interest for potential applications in quantum computing. The SCO phenomenon involves a change of spin state in response to an external perturbation such as change in temperature; the compounds of interest show hysteresis in their solid state susceptibilities. To help understand the structural features that govern this process, we are examining the solution behavior of these systems. NMR relaxation measurements, illustrating the physical magnetic relaxation process, will be correlated with Evans susceptibility measurements, on a series of Fe and Co SCO complexes.

CHED 664

Chromium(3+) binds rapidly to transferrin in the presence of physiological bicarbonate concentrations

Kristi Wu,, Ge Deng, Bin Liu, John B Vincent, of Chemistry, The University of Alabama, Tuscaloosa, AL 35487-0336, United States

Transferrin, the major iron transport protein in the blood, also transports trivalent chromium. In aqueous buffer (with ambient (bi)carbonate concentrations), the binding of chromium to transferrin is slow, taking days to reach equilibrium and too slow to be physiologically relevant. However, in the presence of 25 mM (bi)carbonate, the concentration in human blood, chromic ions bind rapidly and tightly to transferrin. Details of the kinetics of chromium binding to human serum transferrin and conalbumin (egg white transferrin) in the presence of bicarbonate and other major potential chromium ligands in blood will be presented.

CHED 665

Investigating the effect of steric bulk on the catalytic activity of substituted tin(II) chlorides in the esterification of a free fatty acid

Emily A Benton,, Richard W Hartmann.Department of Chemistry and Biochemistry, Nazareth College, Rochester, NY 14618, United States

Recent work in our group has shown tin(II) halides to be effective Lewis acid catalysts for the esterification of a free fatty acid (FFA) with an unusual pattern of reaction rates (I> Br> Cl >F). To confirm that this effect is due to steric bulk, substituted tin(II) chlorides of the form SnCl2X2 (X= Me, Et, t-Butyl) were used as catalysts under the same reaction conditions as the original halides. Reaction rates for the substituted halides follow a similar trend (t-Buytl> Et > Me). We present here the methods used to obtain and analyze our data, our potential mechanisms of this reaction, and our planned future work.

CHED 666

Synthesis of tin (II) halide-phosphine complexes and characterization via 119Sn, 31P, and 19F NMR spectroscopy

Briana Laubacker,, Richard Hartmann.Department of Chemistry and Biochemistry, Nazareth College, Rochester, NY 14618, United States

Recent work in our labs has shown SnX2 (X = F, Cl, Br, and I) to be effective Lewis acid catalysts for the methylation of oleic acid. The results show a clear trend in reaction rates, with SnI2 being the best catalyst and SnF2 the worst. However, we are unable to determine if this result is due to changes in electron density at the metal center, or the steric bulk introduced by the halide ligands. In an effort to systematically modulate the electron density on the tin center we have undertaken the synthesis of several phosphine derivatives of each tin (II) halide using the following phosphines: triphenylphosphine, tris(4-chlorophenyl)phosphine, tris(4-fluorophenyl)phosphine, tris(4-methoxyphenyl)phosphine, tri(p-tolyl)phosphine, 1,2-bis(diphenylphosphino)ethane, and trioctylphosphine. 119Sn, 31P, and 19F NMR studies verify the formation of several novel compounds and this poster will discuss the interpretation of these spectra and the possible identity of the compounds that were formed.

CHED 667

Activation energy determination for the esterification of free fatty acids in oleic acid for biodiesel synthesis using Lewis acid tin (II) iodide

Kristin Nichols,, Richard Hartmann.Department of Chemistry and Biochemistry, Nazareth College, Rochester, NY 14618, United States

Biodiesel is a readily produced and commonly used alternative fuel source. Biodiesel can be synthesized from renewable resources, such as used cooking oil, through esterification of free fatty acids (FFA) or tranesterification of triglycerides. Because used oils are often contaminated with FFA's we have chosen oleic acid as a model system for investigating reactions that convert FFA into methyl esters. An acid catalyst is used to treat the FFA's and create fatty acid methyl esters (FAME). Tin halides are common Lewis acid catalysts and are readily available. Preliminary results show that the rate constants for these reactions fit the following trend: SnF2 < SnCl2 < SnBr2 < SnI2, monitoring the reaction progress using 1H NMR. Based on these results, we have undertaken a series of experiments to determine the activation energies of the reactions. This poster will present my methods and results on the use of tin (II) iodide to catalyze the methylation of oleic acid.

CHED 668

Activation of CO2 by zinc-β-diketiminate complexes

Joshua A. Goodner,, Lei Yang.Department of Chemistry, University of Central Arkansas, Conway, Arkansas 72035, United States

CO2 is one of the most important greenhouse gases and a potential low cost carbon source for both commodity chemicals and complex organic molecules. Therefore, activation of CO2 is not only a significant environmental issue, but also has a great impact in industry level. In recent years, the significant interests in conversion of CO2 by transition metal complexes to value-added products have been continuously increasing. In this project, we focus on the activation of CO2 by zinc-alkyl complexes supported by β-diketiminate ligand platform. Zinc complexes have been synthesized and characterized by NMR, X-ray crystallography, IR and mass spectrum. Interesting reactivities of these complexes with CO2 have been observed in NMR studies.

CHED 669

Synthesis and characterization of dynamic porous coordination polymers (DPCPs) supported by amide ligands

Ethan P. McMoran,, Pyi Thein Kyaw, Lei Yang.Department of Chemistry, University of Central Arkansas, Conway, Arkansas 72035, United States

Guest-host chemistry of small gas molecules, such as H2, N2 and CO2, with dynamic porous coordination polymers (DPCPs) has attracted considerable attention due to the high selectivity and efficiency of these materials. In pursuit of new generation of DPCPs, we synthesized a series of organic ligands functionalized with amide groups, which are expected to significantly improve the flexibility of the framework and improve the interaction between guest molecules and the host surface. Transition metal compounds with various nuclearity have been prepared and characterized by X-ray crystallography, IR, UV-vis, mass spectrum and elemental analysis. The interesting structural and spectroscopic features of these complexes will further enhance the understanding of ligand design and polymer construction, which are major contributors for adsorption properties of DPCP materials.

CHED 670

Construction of low-coordinate iron-sulfur clusters supported by bidentate guanidine ligands

Jamie D. Beck,, Lei Yang.Department of Chemistry, University of Central Arkansas, Conway, Arkansas 72035, United States

The iron-molybdenum cofactor (FeMoco) is the catalytic site of nitrogenase to fix atmospheric nitrogen gas (N2). The high-resolution crystal structure of nitrogenase showed that the belt iron atoms are four-coordinate at rest state. Recent studies indicated the three-coordinate iron might be one of the transition states during catalysis. Our project focuses on the construction of new low-coordinate iron-sulfur clusters supported by bidentate guanidine ligands, which are super-bases with strong coordination donors to metal centers. Two bidentate guanidine ligands were synthesized and characterized by NMR, IR, mass spectrum and elemental analysis. Iron compounds with the ligands have been prepared to react with sulfur source such as S8, NaSH and Na2S. Further characterizations of these compounds are currently underway.

CHED 671

Investigation of the kinetic isotope effect with tin(II) bromide for the esterification of oleic acid

Nandini Singh,, Nicole Bayona,, Nazareth College, Rochester, New York 14618, United States

Biodiesel made from waste cooking oil is a popular substitute for petroleum diesel. However, due to its high content of free fatty acids (FFA), waste oil must undergo an initial acid catalyzed esterification. This process typically employs concentrated H2SO4 but we chose a milder Lewis acid, tin (II) bromide, as our catalyst. Our investigation is part of a larger project which uses oleic acid as a model FFA, and the tin(II) halides (SnF2, SnCl2, SnBr2, and SnI2) as catalysts. Our investigation primarily focuses on the tin(II) halides SnCl2 and SnBr2, because previous research suggests that these two halides are most appropriate for the methylation of oleic acid. Methanol-D was substituted for methanol in order to assess the role of this species in the overall mechanism. Through the use of NMR, we have determined that methanol-D does eventually make methyl ester, but it takes substantially more time for the reaction to occur and it also occurs best at 60ᵒC. Our investigation is done at 55ᵒC and 60ᵒC with both the SnCl2 and SnBr2 halides compare the percent methyl ester created from the different temperature of the two different tin(II) halides. This poster will present our interpretation of the data, how it relates to potential mechanisms, involved in determining the rate limiting steps and the broader impact for the series of tin(II) halides.

CHED 672

Rh(I) complexes of a non-innocent pincer ligand bearing thioether and N-heterocyclic carbene donors

Hannah L Cronk,, Philip L Osburn.Department of Chemistry and Biochemistry, Bloomsburg University, Bloomsburg, Pennsylvania 17815, United States

Although numerous symmetrical pincer-type complexes based on N-heterocyclic carbenes have been studied, unsymmetrical, mixed-donor NHC pincer complexes are far less common. Our previous work with Pd(II) complexes of a pyridine-bridged mixed thioether/NHC (SNC) pincer ligand has demonstrated some unique reactivity patterns endowed by the hybrid, non-innocent ligand system. Expanding upon this work, we now wish to describe the coordination chemistry of our SNC ligand toward Rh(I) and preliminary reactivity studies of the resulting complexes.

CHED 673

How does the metal-metal distance influence the orbitals available for electron transfer in organometallic wires?

Laurel E Howard,, Charity Lovitt.Department of Chemistry, Seattle University, Seattle, Washington 98122, United States

From a chemist's perspective, electron transfer in molecular wires is simply the movement of electrons from an occupied molecular orbital (HOMO) to an unoccupied molecular orbital (LUMO). In order to create an optimal molecular wire, it is necessary to determine structures that encourage metal-metal electron transfer. Triple decker sandwich complexes of the type M1M2(C5H5)3, where M1=Fe, Ru, Os and M2=Fe, Ru, Os have been proposed as the smallest repeating subunits of molecular wires. Using density functional theory (DFT) the M1-M2 distance was varied for each of the triple decker molecule subunits to determine the relationship between M1-M2 distance and the HOMO-LUMO gap. The energy difference between HOMO and LUMO varied from 4.2 to 4.5 eV based on the identity of the metals and decreased as the distance between the two metals increased.

CHED 674

Quantifying the uptake of KP1019 in yeast cells

Kyle J Hoffman1,, Pamela K Hanson2, Laura K Stultz1.  (1) Department of Chemistry, Birmingham-Southern College, Birmingham, AL 35254, United States  (2) Department of Biology, Birmingham-Southern College, Birmingham, AL 35254, United States

Platinum based drugs have been used for years in the treatment of tumors, but these drugs are less than ideal because of their toxicity. A search for other metal-based drugs has led researchers to indazolium trans-[tetrachlorobis(1H-indazole)ruthenate (III)] (KP1019), a novel ruthenium based drug. KP1019 has undergone phase I clinical trials with no dose limiting toxicity. It has been shown that the drug inhibits cell growth, damages DNA, and causes cell death in both cancerous and yeast cells. KP1019 uptake has been observed in mammalian cells, and the purpose of this study was to show uptake in yeast. After a two hour incubation, yeast cells that were treated with KP1019 showed measurable uptake of ruthenium as measured by atomic absorption spectroscopy. This experiment supports the theory that yeast cells are an acceptable model organism to study KP1019.

CHED 675

Chiral thiophosphoramides as ligands for gold(I) catalysis

Kelsey Mesa,, Anna Wenzel.Keck Science Department, Scripps College, Claremont, CA 91711, United States

Thiophosphoramides provide us with the opportunity to design highly versatile ligands for asymmetric catalysis. Monodentate thiophosphoramides can be better suited to serve as ligands for gold(I) over the more conventionally used bisphosphine ligands, as bisphosphines have the potential to create undesired side products due to the reactivity of phosphorus. In addition, the steric distinction provided by the tetrahedral geometry of the phosphorus atom in a thiophosphoramide has the capacity to provide high asymmetric induction. An effective, seven-step synthetic route towards the preparation of these complexes will be discussed, as well as their application as catalysts to effect the asymmetric hydroamination of alkenes.

CHED 676

Imine ligands appended to a polyethylene glycol framework

Lindsay C Wiener,, Bradley M Wile, of Chemistry and Biochemistry, Ohio Northern University, Ada, OH 45810, United States

Progress toward the synthesis of a series of new ligands featuring a PEG moiety is described. These ligands are intended for use in supporting transition metal complexes for aqueous-phase catalysis and recycling.

CHED 677


CHED 678

Lanthanide triple helical complexes with an aminodipicolinic acid derivative

Eliseo E. Quiroz,, Jacob M. Scheckman, Gilles Muller.Department of Chemistry, San Jose State University, San Jose, CA 95192-0101, United States

An organic ligand derived from the aminodipicolinic acid is complexed with three different lanthanide ions, Eu(III), Tb(III), Gd(III), to form triple-helical complexes that lead to chiral emitting species. We hypothesize circularly polarized luminescence (CPL) spectroscopy will confirm the chiroptical activity of these complexes later. We will also determine the stability constants for the different forms of the ligand:metal complexes (i.e. 1:1, 2:1 and 3:1); most importantly the stability constant for the 3:1 complex. Direct excitation spectroscopy was used to study the speciation of the Ln(III):ligand complex solution, whereas the efficiency of the energy transfer from the ligand to the metal ions was investigated using steady-state and time-resolved luminescence measurements. An efficient ligand-lanthanide(III) energy transfer was confirmed with these measurements, but a weak metal-centered luminescent quantum yield may be due to an incomplete intersystem-crossing transfer. The stability constants were determined through spectrophotometric titrations.

CHED 679

Tin(II) halides as catalysts for the methylation of oleic acid

Elana Tontarski,, Richard Hartmann.Department of Chemistry and Biochemistry, Nazareth College, Rochester, NY 14618, United States

Although biodiesel is known to be an effective and environmentally sound replacement for petroleum diesel, it has remained a marginal fuel because of high production costs. The majority of this cost could be eliminated if high free fatty acid (FFA) waste oils were employed as the starting material rather than virgin oils. Because these kinds of oils require acid catalyzed pretreatment, we have been investigating a variety of mild Lewis acids as replacements for the highly caustic and sulfur containing H2SO4 which is the standard catalyst employed. Using oleic acid as a model FFA we have found SnX2 (X = F, Cl, Br, and I) to be an effective catalyst for this reaction and have also observed an interesting trend in reaction rates (I>Br>Cl>F). This poster will present our findings along with a discussion of their significance and the unique use of 1HNMR to determine the rates of these reactions.

CHED 680

Synthesis of metal-organic polymers using 4,5-imidazoledicarboxylate

Natalie Schieber2,, Sydney Combs1, Raj Kishore Vakiti1, Bangbo Yan1, Cathleen Webb1.  (1) Department of Chemistry, Western Kentucky University, Bowling Green, KY, United States  (2) Vanderbilt University, Nashville, TN 42701, United States

Metal organic polymers are a class of compounds composed of organic ligands connecting metal ions. These compounds are valuable because of their large surface area and porosity. The potential applications for these compounds include heavy metal ion capture, carbon capture, and hydrogen fuel cells. We have synthesized four compounds using a variety of organic ligands and metal ions. The ligands include 4,5- imidazoledicarboxylic acid (IDC) and 1,3,5-benzenetricarboxylic acid (BTC). The metal ions were supplied by calcium nitrate, calcium hydroxide, sodium hydroxide, and copper chloride. Variables including ligand composition, time and temperature of heating, and pH were adjusted. The structures of the compounds were obtained using single crystal x-ray diffraction. Powder x-ray diffraction and IR spectroscopy have also been performed for the sodium-IDC compounds.

CHED 681

Kinetics of formation of transition-metal halide complexes of di-2-pyridyl ketone oxime

Michael Remesic,, Barry L. Westcott.Department of Chemistry & Biochemistry, Central Connecticut State University, NEW BRITAIN, CT - Connecticut 06050, United States

Several first-row transition metals were reacted with di-2-pyridyl ketone oxime (dpko) at a 1:1 stoichiometric ratio at both a neutral pH and a pH <2. Novel complex formation with both bromide and chloride ligands were observed and rates of formation were monitored and determined by electronic spectroscopy. Novel complexes incorporating Cu2+ and Ni2+ metal centers reacted nearly instantaneously regardless of coordinating halide, although copper complexes were formed only at acidic pH. Complexes of Co2+ with dpko exhibited slower rates of reaction. Here we present the results of our kinetic studies, along with characterization and proposed mechanisms of formation of the novel complexes.

CHED 682

Systematic modification of electron density on a series of tungsten based Lewis acid catalysts with minimal structural changes

Molly Kingsley,, James Chambers, Richard Hartmann.Department of Chemistry and Biochemistry, Nazareth College of Rochester, Rochester, New York 14618, United States

The results of recent experiments in our group have shown that tungsten compounds (WCl6 and WCl4(PPh3)2) are successful Lewis acid catalysts in the methylation of oleic acid. While it is clear the oxidation state of tungsten influences the rate of reaction, we are unsure of its specific role because both structural and electronic changes were made. In an attempt to investigate the sole effect of electronic changes, we have systematically synthesized a group of compounds of the general formula: WCl4(PPh3-X)2 (X = H, F, Cl, O-CH3, and CH3, all in the para position). These compounds present a scenario where no appreciable change to the structure has been made, yet the electron density of tungsten is influenced from afar. We report here the synthesis, and characterization of these compounds along with a 1H NMR study of their ability to catalyze the methylation of oleic acid.

CHED 683

Synthesis and characterization of transition metal doped SnO2 and TiO2

Joshua S. Page,, Janet L. Hunting.Department of Chemistry, Ithaca College, Ithaca, New York 14850, United States

New materials are needed to replace carbon black as the cathode support in proton exchange membrane fuel cells. Tin(IV) oxide and titanium(IV) oxide were chosen as host materials due to their low cost, acid resistance, and non-toxicity. SnO2 and TiO2 were doped with molybdenum, niobium, tungsten, tantalum and iron, with substitutions of 5–40%, to form new compounds that maintain the rutile structure of the host material. The new compounds, both singly- and multiply-doped, were synthesized by grinding together powders in the correct stoichiometric ratios followed by heating to 950–1100 °C for 6 days in sealed quartz tubes. The resulting powders were characterized using single-crystal X-ray diffraction, X-ray fluorescence, resistivity tests and powder X-ray diffraction.

CHED 684

Molybdenum- and tungsten-doped tin(IV) oxide compounds prepared by sol-gel for PEM fuel cell cathode supports

Automm R. Lombardo,, Janet L. Hunting.Department of Chemistry, Ithaca College, Ithaca, New York 14850, United States

Tin(IV) oxide is able to withstand the environment of a proton exchange membrane fuel cell; however, SnO2 has a high resistance to electron flow and alone cannot be used as an alternative cathode support. The rutile structure was doped with transition metals (tungsten, niobium, molybdenum, cobalt, and iron) to improve conductivity. Synthesis was performed with the sol-gel method, using metal isopropoxides as starting materials. Sn0.7W0.3O2, Sn0.7Mo0.3O2, Sn0.7W0.2Mo0.1O2, Sn0.7W0.2Nb0.1O2, Sn0.7W0.2Co0.1O2, Sn0.7W0.2Fe0.1O2, and Sn0.7Mo0.2Co0.1O2 were synthesized. These compounds were characterized by powder X-ray diffraction, X-ray fluorescence, and resistivity and acid tests.

CHED 685

Project SHArK at Suffolk University

Katharina Feister,, Blerta Milo,, Rachael A Kipp, of Chemistry and Biochemistry, Suffolk University, Boston, MA 02114, United States

Due to their abundance, band gap size, and inherent stability, metal oxide semiconductors seem to be a promising avenue to efficiently and inexpensively photoelectrolyze water, producing hydrogen that could later be used as an energy carrier. No one metal oxide semiconductor or combination of different metal oxides is currently known to proficiently split water to generate hydrogen.

Due to the vast number of possible combinations, a distributed research project called the Solar Hydrogen Activity Research Kit (SHArK) Project was created by Bruce Parkinson (University of Wyoming), in order to mobilize many different schools to test various metal oxide combinations for their effectiveness. The Suffolk University SHArK group has collected data using the pipetting method. High precision has been obtained across multiple users and sites. Preliminary results indicate that several metal oxide combinations show increased photoelectrolysis activity.

CHED 686

Effect of dendritic and chromophoric ancillary ligands on the color-tuning and efficiency of phosphorescent cyclometalated iridium (III) complexes

Emily F. Amond,, Jason K. Vohs.Department of Chemistry, Saint Vincent College, Latrobe, PA 15650, United States

The quickly advancing technology of organic light-emitting devices (OLEDs) and flat panel displays requires new and better materials to increase their efficiency and the spectrum over which they can be color-tuned. Phosphorescent iridium (III) complexes have been shown to be effective in the fields of photochemistry and optoelectronics because of their high quantum efficiency. Iridium (III) complexes were synthesized which contained both dendritic and chromophoric ligands. In addition to the identity of the chromophoric ligand, the effects of increasing dendrimer generations on the complexes were studied. The complexes were characterized by 1H NMR spectroscopy, and the photoluminescent properties of the complexes were measured by UV-vis and fluorescence spectroscopy. The incorporation of both types of ligands into the complexes was attempted as a way to expand the emitted color spectrum without compromising the initial efficiency of the complexes, which could have a positive impact on the further improvement of OLED displays.

CHED 687

Synthesis of a polymer bound copper-hydride catalyst

Liz A. Closurdo,, Stacy A. O'Reilly, of Chemistry, Butler University, Indianapolis, Indiana 46208, United States

In the early 1990's a copper-hydride catalyst developed by Stryker and co-workers was heralded as a major advancement in the conversion of a,b-unsaturated ketones to saturated ketones. A polymer bound copper-hydride catalyst based on Stryker's reagent has been synthesized. The polymer bound copper-hydride catalyst was used to convert cyclohexanone to a silyl enol ether. The copper catalyst was removed from the reaction mixture by filtration, isolated and reused.

CHED 688

Evaluation of possible electrocatalysts for the reduction of carbon dioxide and/or protons utilizing cyclic voltammetry

Marryssa Russell,, Jean MacPetrie Ogden, Justin Edmonds, Tad Schrader, David R. Weinberg.Department of Physical and Environmental Sciences, Colorado Mesa University, Grand Junction, CO 81501, United States

Problems with storing solar energy efficiently have significantly limited its utilization. We are addressing this issue through the search for inexpensive catalysts that could efficiently combine solar electricity with carbon dioxide and/or protons to generate fuels. These fuels could then be stored and burned for energy as needed. In order to find electrocatalysts that can reduce carbon dioxide and/or protons at relatively positive potentials, we are focusing on inexpensive, solution-phase organic molecules and transition metal complexes that will likely transfer both protons and electrons simultaneously. Possible catalysts are being tested using cyclic voltammetry in both organic and aqueous solutions, and they are being evaluated based on the potentials and currents involved in their reductions of carbon dioxide and/or protons.

CHED 689

Recent developments in the syntheses of a series of podand ligands utilizing the amines: Diethylenetriamine, triethylenetetraamine, or spermine, and a variety of functional aldehydes

Candice Kashat,, Chanel Pattah, Antoinette Mordi, Osama A Elghondi, Hassan A Masloum, Mark A Benvenuto.Department of Chemistry & Biochemistry, University of Detroit Mercy, Detroit, MI 48221-3038, United States

A series of ligands utilizing diethylenetriamine, triethylenetetraamine, or spermine, and utilizing further functionality through the addition of aldehydes via Schiff's Base condensations, have been synthesized. Each is a multi-dentate neutral molecule containing a minimum of two nitrogen donor atoms and possibly two oxygen donor atoms. Structural characterization has been predominantly by 1H and 13C nuclear magnetic resonance spectroscopy. This, plus the metal binding capabilities of the ligands, will be presented.

CHED 690

Use of 4,4'-diaminodicyclohexylmethane to form a series of multi-dentate ligands and selected lanthanide metal complexes thereof

Shelby D Maurice,, Antoinette Mordi, Chanel Pattah, Alexis Konja, Mustansir Hussain, Mark A Benvenuto.Department of Chemistry & Biochemistry, University of Detroit Mercy, Detroit, MI 48221-3038, United States

A series of bis-bidentate ligands, each utilizing 4,4'-diaminodicyclohexylmethane (DADCM), and a functional aldehyde, were generated through Schiff's base condensations. Synthesis and characterizations of the ligands by NMR, and of selected metal complexes of them via NMR and single crystal structure (where possible), will be presented and discussed.

CHED 691

Use of 1,2-diaminocyclohexane as a synthon to form multi-dentate ligands, and selected metal complexes thereof

Sarah Vella,, Mark A Benvenuto.Department of Chemistry & Biochemistry, University of Detroit Mercy, Detroit, MI 48221-3038, United States

A series of tetra-dentate ligands, each utilizing 1,2-diaminocyclohexane, and a functional aldehyde, were generated through Schiff's base condensations. Synthesis and characterizations of the ligands by NMR, and of selected metal complexes of them, will be presented and discussed.

CHED 692

Synthesis and structure of diacetyl-4,4-dimethyl-4'-methylbis(thiosemicarbazone) with select transition metals

Max Thompson,, Willis Weigand.Department of Chemistry, Southwestern University, Georgetown, Texas 78626, United States

Bis(thiosemicarbazone) complexes have shown a wide variety of uses over the past few decades. A number exhibit strong anticancer capabilities, while others show antileukemic properties. Others find use as imaging agents, and a recent development presents the possibility of the use of a bis(thiosemicarbazone) complex in fighting Alzheimer's disease. Diacetyl-4,4-dimethyl-4'-methylbis(thiosemicarbazone) is a bis(thiocarbazone) that is frequently seen as an intermediate in the synthesis of more complex ligands, and, as such, has been the subject of less investigation. This ligand has been synthesized and reacted with a variety of transition metal ions. The resultant complexes have been characterized through NMR and IR. Additionally, the crystals of these metal-ligand complexes have been isolated and x-ray crystallography was performed.

CHED 693

Studies of the microwave assisted borohydride catalyzed reaction of rheniumpentacarbonyl halides with chelating phosphines

Kristina Martinez,, Kurt R. Birdwhistell.Department of Chemistry, Loyola University New Orleans, New Orleans, LA 70118, United States

We have studied the microwave assisted reaction of rhenium pentacarbonyl halides, ( X =Cl, Br) with chelating phosphines. The reactions were catalyzed by borohydride and heated by a microwave to rapidly form new rhenium carbonyl complexes under mild conditions. The products were purified by column chromatography and characterized by NMR, IR, and ES-MS. Details of the reaction and microwave parameters, and spectroscopic results will be discussed.

CHED 694

Synthesis and characterization of cobalt(III) compounds for inorganic chemistry laboratory manual

Amy Kloosterboer,, Evonne M Rezler.Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States

We have recently developed an Inorganic Chemistry Laboratory Manual at Florida Atlantic University to provide undergraduate chemistry students the opportunity to learn in a “hands-on” environment key concepts in coordination chemistry. This experiment will incorporate different synthetic and analytical techniques with a discovery-based focus on the study of coordination compounds, crystal field theory, the spectrochemical series, and the counter ion effect. The students will synthesize three related cobalt compounds and their respective geometrical or optical isomers. They will use these compounds to perform two different microscale cation exchange column chromatography experiments involving separation and purification based on charge and polarity. The last section of the experimental procedure will be devoted to the characterization of all compounds using IR, UV-Vis, and for the first time in the Inorganic Chemistry curriculum, Raman Spectroscopy.

CHED 695

New dirhenium paddlewheel compounds with alternating O,O'- and N, N'- bridging ligands

Michael J Tarne,, Michael Q Dequeant.Department of Chemistry, Hendrix College, Conway, AR 72032, United States

Dirhenium paddlewheel compounds have shown unique structural and photophysical properties due to the quadruple bond between rhenium atoms and the bridging ligands between the rhenium atoms. Many of these compounds have had only one type of bridging ligand between the rhenium atoms. In this project, Re2(OAc)2Cl4 is reacted with formamidine ligands ((p-XArN)2HCH; X = -H, -Cl, -OCH3, -CH3, -C(O)CH3) under various conditions to give Re2(III, III) paddlewheel compounds with alternating bridging acetate and formamidinate ligands and axial chloride ligands. Preliminary results of the compounds' structural and photophysical properties and electrochemical behavior will be presented.

CHED 696

Synthesis of zero, one, and 2D copper(I)-pyrazine complexes

Michael J. Anderson2,, Bangbo Yan1, Cathleen Webb1.  (1) Department of Chemistry, Western Kentucky University, Bowling Green, KY 42101, United States  (2) Department of Chemistry, Columbus State University, Columbus, GA 31907, United States

Crystal engineering of coordination polymers has been a prominent area of interest in solid material research. The coordination number and orientation of transition-metal binding sites with organic ligands and connectors constitutes an array of atoms ideal for the establishment of a unique framework in association with a desired porosity and large surface area. Applications of these porous materials include ion exchange networks for the removal of toxic metals in waste water, and porous frameworks with tunable electrical, optical and magnetic properties. Our experiments in the synthesis of copper based complexes using the aromatic nitrogen heterocycles ligands have led to four structures: [Cu(pzc)2(H2O)2], [Cu(pzc)2], [CuCl(pzc)2(H2O)2], and [CuCl(pz)2] (pzc = 2-pyrazinecarboxylate; pz = pyrazine).

CHED 697

Preparation, characterization, and activity studies of palladium catalysts on alumina and silica supports

Michael J. Anderson,, Anil Banerjee.Department of Chemistry, Columbus State University, Columbus, GA 31904, United States

Palladium catalysts were prepared by dry impregnation and wet incipient methods of metal nitrate solutions being added to slurry of alumina and silica supports separately; this was finalized by drying in an air oven and calcination in a tube furnace at 600 °C for two hours. Characterization of the catalysts involved several techniques including a) pulse chemisorption; b) Brunauer-Emmett-Teller (BET) method of physical adsorption to measure total surface area; c) Temperature Programmed Oxidation (TPO); and d) Temperature Programmed Desorption (TPD) to determine active sites of the catalysts. Pulse, TPO/TPD studies were conducted with Micromeritics 2705 Chemisorb equipment. Dispersion of Pd on alumina was 35%, TPD of this catalyst showed hydrogen desorption at 300-550 ºC indicating hydrogen was adsorbed even at high temperature. Activity studies are being done using CO oxidation (1% CO and oxygen) on selective catalysts. The data on catalytic properties as well activity studies will be presented.

CHED 698

Reaction rates of amino acids with analogs of the anticancer drug cisplatin

Celia J. Whelan,, Kevin M. Williams.Department of Chemistry, Western Kentucky University, Bowling Green, Kentucky 42101, United States

We are studying the reactions of various amino acids with analogs of the anticancer drug cisplatin that differ in both size and shape. Reaction of cisplatin with proteins likely precedes reaction with DNA in the body, and both size and shape of the platinum complexes often affect the reactions with protein targets more than with DNA targets. In this study, cisplatin analogs have been reacted with the amino acid histidine, and the reactions have been monitored by NMR spectroscopy. Rate constants were calculated and, when compared to previously obtained constants, it has been seen that adding bulk to the platinum compound has little to no effect on the reaction with histidine compared with other targets such as methionine. Thus, sufficient bulk may increase the relative number of histidine adducts compared with methionine adducts.

CHED 699

Complete oxidation of nitrogen heteroatoms in aromatic amines

Nathan G Strom,, Katharine M Brown, Peter Baran.Department of Chemistry, Juniata College, Huntingdon, PA 16652, United States

The complete oxidation of pyridazine and pyrazole has never been accomplished using usual oxidizing agents such as peroxides, peroxoacids, permanganates, or chromates. Only mono N-oxides of unsubstituted pyridazine and pyrazole have been reported. The HOF·CH3CN complex, that demonstrated the ability to completely oxidize 1,10-phenantroline to 1,10-phenanthroline N,N′-dioxide1 was therefore chosen as the oxidizing agent. Pyridazine N,N′-dioxide and pyrazole N-hydroxide, N′-oxide were isolated when HOF·CH3CN was used. The new organic compounds that are promising ligands in coordination chemistry were characterized using IR, GCMS, elemental analysis, and X-ray crystallography. The pyridazine dioxide was then complexed with CuCl2. IR spectroscopy, elemental analysis, and X-ray crystallography were used to study the composition of the complex.

1 S. Rozen, S. Dayan, Angew. Chem. Int. Ed. 1999, 38, 3471.

CHED 700

Synthesis, characterization, and initial biophysical reactivity of [η6-(C6H6)Ru(curcuminoid)Cl] complexes

Kinsey L Hall1,, Shylene A Scott2, Floyd A Beckford1.  (1) Department of Natural Sciences, The University of Virginia's College at Wise, Wise, VA 24293, United States  (2) Lyon College, Batesville, AR 72501, United States

We have synthesized a series of organometallic ruthenium piano-stool complexes with curcuminoids as co-ligands from the reaction of [(C6H6)RuCl2]2 with the curcuminoid in a methanolic solution containing potassium hydroxide. The complexes have been characterized by elemental analysis and various spectroscopic methods. The hydrolysis (defined as the replacement of the chloride ligand by a water molecule) of the complexes shows a complicated behavior with rates constants ranging from 1.1 x 10-5 s-1 to 1.2 x 10-4 s-1. We have also investigated the interaction of the complexes with calf-thymus DNA using absorption and fluorescence spectroscopies as well as viscometric methods. From UV-Vis absorption spectrophotometry the binding constant with calf-thymus DNA is 103 – 104 M-1.

CHED 701

Progress toward synthesis of phenyl-substituted spirometallabifluorenes

Patrick M Wallace1,, Jerome L Mullin2, Caryn K Prudenté1, Henry J Tracy1.  (1) Department of Chemistry, University of Southern Maine, Portland, Maine 04104, United States  (2) Department of Chemistry and Physics, University of New England, Biddeford, Maine 04005, United States

Group 14 metalloles have been shown to demonstrate an aggregation induced emission (AIE) phenomena. Our group is interested in synthesis and characterization of these highly fluorescent compounds, and we have been successful in producing several new spirometallabifluorenes. The unusual photophysical properties of these compounds may make them suitable for practical applications such as labeling biological molecules, fabrication of OLEDs, chemical sensors, and optoelectronic devices. Progress and results toward synthesizing these novel metalloles will be presented.

CHED 702

Synthesis of group 14 metalloles

David J Tiberi,, Jason K Vohs.Department of Chemistry, Saint Vincent College, Latrobe, Pennsylvania 15650, United States

Research on the properties of heterocyclopentadienes has been conducted over the past 50 years, and this class of molecules has recently been employed in the conductive polymer layer of some organic light-emitting diodes (OLEDs). Heterocyclopentadienes containing metals, also known as metalloles, have demonstrated excellent electron transport abilities which stimulated their use in this way. Through altering the metal contained in the metallole, the band gap of these molecules can then be tuned. Metalloles were synthesized containing group 14 metals. These compounds were characterized by 1H NMR spectroscopy and X-Ray crystallography if applicable. The replacement of the metal contained within the molecule allows for the properties to be altered while the substituents stay the same. These molecules can then be altered to be used as monomers for poly-metallole synthesis.

CHED 703

Cobalt catalyzed production of aromatics using C6F5CpCo(CO)2

Christopher Houser,, Eric Hawrelak.Chemistry and Biochemistry, Bloomsburg University of Pennsylvania, Bloomsburg, Pennsylvania 17815, United States

This study examines the catalytic synthesis, via an organocobalt catalyst [C6F5CpCo(CO)2], and purification of triphenylbenzene (TPB), biphenyl picolene (BPP), and tris(trimethylsilyl)benzene (TTMSB). TPB and TTMSB were prepared via the reaction between phenylacetylene and tetramethylsilane(TMS) respectively with 10 mol % of catalyst in refluxing octane. The BPP was prepared via the reaction between phenylacetylene and 10 mol % of catalyst in refluxing acetoniltrile. The purification process for each molecule began with a thin layer chromatography was then run on a Grace Davison Flash Chromatography Instrument. The synthesis of each molecule was determined via NMR in CDCl3. The yields for these reactions are still being optimized and at a 75:1 acetonitrile to phenylacetylene molar ratio, BPP can be made exclusively from TPB.

CHED 704

Palladium(II) and platinum(II) terpyridine complexes with 4-substituted pyridines: Building blocks for synthesis of heteronuclear complexes

Daniela Canales,, Rafael A Adrian, of Chemistry, University of the Incarnate Word, San Antonio, Texas 78209, United States

New palladium and platinum complexes have been synthesized by the reaction of M(terpy)(NO)3 (where M =Pd(II) or Pd(II) and terpy = 2,2':6',2''-terpyridine) with 4-substituted pyridines. In these complexes the ligand coordinates through the nitrogen in the pyridine ring to the Pd(terpy)2+center leaving the functional groups in the 4-position available for interaction with other complexes. The characterization of these complexes and their reactivity towards the formation of heteronuclear complexes will be discussed.

CHED 705

Ruthenium complexes with functionalized-pyridines: Building supramolecular networks through hydrogen bonding

Brayan Quintela,, Rafael A Adrian, of Chemistry, University of the Incarnate Word, San Antonio, TX 78209, United States

New ruthenium(II) complexes have been synthesized by the reaction of Ru(bpy)2(NO3)2 (where bpy = 2,2'-bipyridine) with isonicotinamide and 4-picolylamine. In both complexes the ligands N-coordinate to the Ru(bpy)22+ metal center leaving the amino groups available for hydrogen bonding. The characterization of these complexes and their reactivity towards the formation of supramolecular structures will be discussed.

CHED 706

Theoretical investigation of the utility of ammonia borane derivatives for hydrogen storage

Justin Mark,, Andrew S. Dutton.Department of Chemistry and Biochemistry, Suffolk University, Boston, Massachusetts 02114, United States

Ammonia borane has become an interesting compound of study with its high hydrogen content of ~19% (wt/wt), making it a plausible fuel in the possible switch to hydrogen energy. Releases of hydrogen molecules off of ammonia borane derivatives were simulated in Gaussian 09, using the B3LYP/6-311+G(d,p) and CBS-QB3 levels of theory, in order to study the free energies of the reactions. Substituents with varying degrees of electron donating and withdrawing power were selected in order to study the shifts in the free energies of the derivatives, after hydrogen release, compared to those of regular ammonia borane. The substituents seem to have similar patterns in terms of affecting free energies, regardless of being bonded to the boron or nitrogen atom of ammonia borane. Based on the calculated energies, it seems that ammonia borane derivatives may be useful for hydrogen storage, but a significantly large energy barrier is present between hydrogen releases.

CHED 707

Synthesis and characterization of novel monosubstituted copper dimer liquid crystals

Matthew Pinkelton1,, Thomas Clayton1, Mark Shroyer2, Emma Lorenzen2, Paul Heiney3.  (1) Department of Chemistry, Knox College, Galesburg, Illinois 61401, United States  (2) Department of Physics, Knox College, Galesburg, Illinois 61401, United States  (3) Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States

Reaction of copper (II) carboxylate dimers with copper (II) chloride dihydrate produces a chloride bridged intermediate as shown by FT-IR. Addition of a new carboxylate ligand forms a monosubstituted product which has been identified by elemental analysis, DSC, FT-IR, polarized optical microscopy, SQUID magnetic susceptibility, and variable temperature XRD. These monosubstituted products exhibit liquid crystalline mesophases. Melting points for mixed ligand products are much lower by comparison with copper(II) butanoate parent specie. Both X-ray diffraction and polarized optical microscopy suggest that the rectangular columnar mesophase of the copper(II) butanoate parent is disrupted. The new mesophase exhibits a drastically lowered melting point but retains the antiferromagnetic behavior consistent with the copper dimer molecular structure.

CHED 708

Popularizing N-oxide coordination chemistry via a novel synthetic approach to the ligand precursor 2-pyridinecarboxaldehyde N-oxide

Alexander B Koval,, Peter Baran.Department of Chemistry, Juniata College, Huntingdon, PA 16652, United States

Schiff bases containing a pyridine N-oxide moiety attract much less attention from coordination chemists than their pyridine analogues or Schiff bases derived from salicylaldehyde. The main reason is commercial inaccessibility of 2-pyridinecarboxaldehyde N-oxide (poxal) and its peculiar synthesis requiring oxidation of α-picoline N-oxide by selenium dioxide. Several alternative synthetic routes for poxal have been suggested recently, but with little success, to increase popularity of N-oxide coordination chemistry due to their complicated procedures. We are presenting a simple and efficient two-step synthesis of poxal by employing oxidation of protected 2-pyridinecarboxaldehyde. The details of the synthetic procedure of poxal together with the synthesis and full characterization of copper(II) complexes of its intermediates will be presented.

CHED 709

Investigations of influence of various cupric salts on formation of pyridine N-oxide Schiff bases

Avery H. Fordham,, Peter Baran.Department of Chemistry, Juniata College, Huntingdon, Pennsylvania 16652, United States

Attempts to synthesize a tetradentate Schiff-base (L) via condensation of two equivalents of 2-pyridinecarboxaldehyde N-oxide (poxal) with o-phenylenediamine resembling salen-type ligands yielded a bidentate ligand 2-(2-benzimidazolyl)pyridine N-oxide (poxbim) in a low yield. When the reaction is performed in the presence of a base, a tridentate Schiff base (poxpam), the product of 1:1 (aldehyde:amine) condensation, was isolated. The subsequent condensation of poxpam with additional equivalent of poxal yields the desired tetradentate Schiff base L. A Cu(II) complex with L was obtained via a templated synthesis of poxal and o-phenylenediamine with Cu(NO3)​2. However, Cu(NO3)2 causes poxpam to be catalytically converted to poxbim. Results of complexation studies of poxpam and templated syntheses of L using different cupric salts (chloride, sulfate, and acetate) will be presented together with characterization of isolated complexes.

CHED 710

Structural studies of molybdenum halide clusters

Trevor H. Sams,, Dean H. Johnston.Department of Chemistry, Otterbein University, Westerville, OHIO 43081, United States

Molybdenum halide clusters have been studied extensively due to their unique photophysical and electrochemical properties. Phosphorescent lifetimes as long as 300 μs have been observed in solution measurements. We have prepared a series of molydenum halide clusters, [Mo6X8L6]2- (X = Cl, Br, I), and characterized them using single crystal X-ray diffraction.

We have shown that the nature of the "outer" ligand (L) influences both the photochemical properties of the compound and the structure of the cluster core. We are also developing routes to build hydrogen-bonded networks of cluster units.

CHED 711

Ru(II) complexes for potential use in studies of nitrogenase activity

Lorena I Zuniga,, Robert N Garrner, of Chemistry, University of the Incarnate Word, San Antonio, TX 78209, United States

The ability to test nitrogenase activity has a very useful application in biochemistry. Current methods, which test nitrogenase activity by monitoring the reduction of acetylene to ethene or ethane, are cumbersome and are generally lower throughput. A potential new high throughput method using Ru(bpy)2(CN)2 and other Ru(II) cyano complexes to monitor the nitrogenase reduction of the cyano ligand by electronic absorption is being studied.

CHED 712

Variable-temperature structural changes and resultant photoluminescent effects in isostructural lanthanide cyanometallates containing Au2Pt4 and Au2Pd4 cyanide clusters

Kang Rui Xiang1,, Anthony Thames1, Frankie White1, Lam Pham1, Zerihun Assefa2, Richard E. Sykora1.  (1) Department of Chemistry, University of South Alabama, Mobile, AL 36688, United States  (2) Department of Chemsitry, North Carolina A&T State University, Greensboro, NC 27411, United States

Four isostructural compounds with the formula K2[Ln(H2O)4(M(CN)4)2]Au(CN)2⋅2H2O (Ln = Eu, Gd; M = Pt, Pd), abbreviated KLnMAu, will be discussed. Studies of said compounds will be presented with four foci. First, Au2Pt4 or Au2Pd4 clusters within the compounds have the potential to transfer energy to either Gd3+ or Eu3+ in KLnMAu. Such potential was studied via temperature-dependent photoluminescence experiments. With Gd3+ having no visible emission, it acts as a control for energy transfer from cyanide clusters to Eu3+. Second, the difference in degree of covalency in metal-metal interactions in the Au2Pt4 vs Au2Pd4 clusters will be presented. Third, M-Au and Au-Au distances, cell volumes, and a-axis and c-axis unit cell lengths of all four compounds were recorded with X-ray diffraction. Changes in those properties with respect to change in temperature will be displayed. Finally, variable-temperature structural and photoluminescence changes will be correlated.

CHED 713

Addition of triphenylphosphine oxide ligands to the europium dicyanoaurate system

Anthony T Thames1,, Kang Rui Xiang1, Lam Pham1, Frankie White1, Zerihun Assefa2, Richard E. Sykora1.  (1) Chemistry, University of South Alabama, Mobile, Alabama 36618, United States  (2) Chemistry, North Carolina A&T State University, Greensboro, North Carolina 27411, United States

One of the properties of europium is that it has a high number of coordination sites available for the bonding of ligands. Another property of europium is that its trivalent state displays a characteristic red emission. This research focuses on the synthesis of the europium complex Eu[Au(CN)2]3[OPPh3]4. Energy transfer between the ligands and europium were compared to the energy transfer seen in Eu[Au(CN)2]3 · 3H2O and Eu(OPPh3)3(SCN)3. The structure of Eu[Au(CN)2]3[OPPh3]4 was determined by low-temperature singe crystal X-ray diffraction. X-ray diffraction shows that the structure of the complex is a coordination compound that uses the dicyanoaurate as a bridging ligand between adjacent Eu3+ ions. These experiments also reveal that the structure of the complex is anhydrous, although the reaction conditions did not exclude water or air. Temperature dependent luminescence spectra show that there is indeed energy transfer between triphenylphosphine oxide and Eu as well as the dicyanoaurate and Eu.

CHED 714

Routes toward the synthesis of symmetrical triazole N-heterocyclic carbenes

Bryan Haugen,, Marites A. Guino-o.Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55104, United States

Enders have shown that 1,3,4-Triphenyl-4,5-dihydro-1H-1,2,4-triazol-5-ylidene (TPT) is a stable carbene in the absence of oxygen and moisture. However, since its preparation in 1995, only a few groups have investigated new routes towards this carbene. Herein, we present our attempts in the synthesis of symmetrical triazole based N-Heterocyclic carbene precursors. These precursors will be used to investigate steric effects on a nickel center.

CHED 715

Stabilization of group 13 metal complexes by utilization of the sterically hindered N-heterocyclic carbene, iPR

Allen J. Osinski,, Jason K. Vohs.Department of Chemistry, Saint Vincent College, Latrobe, Pennsylvania 15650, United States

Carbenes are organic molecules that contain a neutral divalent carbon with only six valence electrons. One type of carbene is the N-heterocyclic carbene (NHC). Recently, N-heterocyclic carbenes with large sterically hindering aryl groups have been used to prepare many intriguing main group metal complexes. Here, we report the utilization of the extremely bulky iPr* NHC ligand in the formation of group 13 metal halide complexes. Although this ligand replaces the methyl groups of iPr NHC with phenyl groups, it has been shown in the literature to be malleable enough to contain transition metal centers within the gap surrounding the carbene center.

CHED 716

Borohydride catalyzed preparation of new group six carbonyl complexes: PEG modified reactivity

Ronny Lem,, Kurt R. Birdwhistell.Department of Chemistry, Loyola University New Orleans, New Orleans, LA 70118, United States

We studied the synthesis of group six carbonyl complexes using microwave energy and borohydride catalysts. By combining these technologies, we have devised a low temperature, low pressure, rapid synthesis of group six carbonyl complexes of M(CO)4dppe and M(CO)3dppe(η1-dppe) , where M = Mo, or W. We will present data on these syntheses including: microwave time and temperature, use of green solvents, counterion effects, and product results. We will compare this synthesis to conventional non-microwave preparations of the group six carbonyl complexes using the Chatt synthesis.

CHED 717

Langmuir-Blodgett studies of organosilyl derivatized Dawson polyoxotungstates

Eric Lemieux1,, Elizabeth J. O. Atkinson1,, R. Carlisle Chambers2.  (1) Department of Chemistry, Linfield College, McMinnville, OR 97128, United States  (2) Department of Chemistry, George Fox University, Newburg, OR 97132, United States

Polymetaloxalates are polyatomic ions consisting of three or more transition metal oxyanions linked together by shared oxygens. The goal of this study was to characterize organic-derivatized Dawson polyoxotungstates. Alkylated Dawson derivatives were synthesized by covalently attaching organosilyl groups of differing lengths [(Si2O)(CnHn+1)2 where n=8 or 12] to Dawson lacunary head groups. The derivatives were precipitated by the addition of tetrabutylammonium counter ions. The products were characterized by 1H and 31P NMR and further studied using Langmuir-Blodgett techniques to examine their amphiphilic properties.

CHED 718

Acylation of ferrocene: Which is greener?

Maria Swasy,, Jason K Vohs.Department of Chemistry, Saint Vincent College, Latrobe, PA 15650, United States

The acylation of ferrocene is a commonly performed reaction in undergraduate inorganic laboratories because it demonstrates Friedel-Crafts acylation and it introduces students to metal-arene complexes. With increased concern about the negative impacts that many chemical reactions are having on our environment, green chemistry has become more of an emphasis in classrooms and laboratories. Various procedures that have already been presented as being greener than the traditional acylation of ferrocene will be compared to one another using qualitative and quantitative methods. The 12 Principles of Green Chemistry and green chemistry mass metrics will be used to evaluate the greenness of each of these reaction pathways. The green star representation of these pathways will visually show the greenness of each pathway.

CHED 719

Synthesis and characterization of macrocyclic dimetallic complexes of copper, nickel, and zinc

Kacey L McQuiston,, Karina N Juarez,, Brian G McBurnett.Department of Chemistry, University of the Incarnate Word, San Antonio, Texas 78209, United States

Towards the development of non-platinum antitumor compounds, a series of mixed metal macrocyclic complexes were synthesized. A macrocyclic oxyimine ligand was used as a template for a series of symmetric and asymmetric dinuclear complexes of copper, nickel, and zinc. Potentially active in the binding and hydrolysis of DNA, the synthesis, structure, and characterization of these complexes will be discussed.

CHED 720

Luminescence study of the effect of firing times on the stability of divalent samarium in barium octaborate

Christopher H Drozdowski,, Nathan A Stump;.Department of Chemistry, Winston-Salem State University, Winston-Salem, North Carolina 27110, United States

The product of the homogenous coprecipitation of samarium(III) and barium(II) with sodium tetraborate can be fired in air with an equivalent mass of boric acid producing divalent samarium in barium octaborate (BaB8O13). This process has been studied for 1 and 5 mole percent samarium versus barium samples as a function of firing times using emission spectroscopy. The reduction to divalent samarium in both samples was observed to increase steadily with maximum reduction occurring at 30 minutes firing time. As firing times extended beyond 30 minutes, the divalent samarium increasingly oxidized to trivalent samarium. It was observed that firing of the 5% samarium sample beyond 4 hours resulted in a change in the divalent samarium ion's site as indicated by the samarium(II) emission spectrum. The new site has not been previously reported, but is believed to result from the formation of divalent samarium in barium hexaborate (as BaB6O10 or BaB6O10•B2O3).

CHED 721

Computational and experimental studies of cyanoethylene pentacarbonyl metal (molybdenum and tungsten) complexes: Insights into η2 and η1 competitive bonding

Austin Stewart,, Sheryl L Johnson, Ted W. Camper, Alexus Rusk, David L Cedeño.Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, United States

The bonding of cyanoethylenes to M(CO)5 (M = Cr, Mo, W) could lead to either olefin binding (via the C=C bond, or η2) or nitrogen binding (η1). A recent report by Bubrin et al.1 indicate that the η1 bonding mode is preferred over the η2 mode in W(CO)5(C2(CN)4) counter to what had been previously reported. We have carried out computational (DFT) modeling of the η1 and η2 bonding for the full series of M(CO)5(C2Hn(CN)n) (M =Mo, W and n = 1 to 4) and found out that η1 is preferred in all cases. Furthermore, the preference increases with an increase of the number of cyano substituents. We have also synthesized M(CO)5(E-C2H2(CN)2) and M(CO)5(C2(CN)4) (M = Mo, W) and measured their thermal decomposition kinetics. Experimental results agree with the computational predictions. Analyses of the aspects that govern the preference of η1 bonding over η2 bonding are discussed.

1. Organometallics, 2012 , 31, 6305

CHED 722

Computational study of phenylethylene pentacarbonyl metal (chromium, molybdenum and tungsten) complexes: The influence of steric effects on metal-olefin bonding

Stephen A. Hon, Konrad L Ryba,, David L Cedeño.Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, United States

It is widely accepted that steric interactions influence the bond strengths between a ligand and a transition metal in a complex. In the case of olefins as ligands, however, the extent of this influence has not been incorporated in the model used to describe a metal-olefin interaction. Here we present a computational (DFT) study that quantitative describes the role of steric interactions in the bonding of a series of phenylethylenes (C2H4-n(Ph)n, Ph = phenyl, n = 0 – 4) to M(CO)5 (M = Cr, Mo, W). The results indicate that there is almost a linear decrease of the bond strength with the increase of the number of phenyl substituents and that triphenylethylene and tetraphenylethylene will not make stable olefin complexes. Indeed, results indicate that η2 bonding to a phenyl substituent would be preferred when steric interactions restrict binding to the olefin.

CHED 723

Synthesis and characterization of new aminophenol ligands

Sarah R. DiNapoli,, Courtney A. Downes, Joshua R. Farrell.Department of Chemistry, College of the Holy Cross, Worcester, MA 01610, United States

We are developing a strategy for preparing a library of diaminotetraphenol ligands containing one to four different phenols in one compound. The synthesis of the ligands is based on a series of sequential reductive amination reactions, beginning with a substituted salicylaldehyde and 1,3-diaminopropane. Multidentate aminophenol compounds have applications as ligands for biologically relevant metals, for bioinorganic modeling chemistry and in catalysis. The synthesis and characterization of these new ligands as well their metal complexes will be reported.

CHED 724

Synthesis and characterization of hybrid thiophene-aminophenol ligands

Kevin M. Turner,, Matthew R. Zielinski, Joshua R. Farrell.Department of Chemistry, College of the Holy Cross, Worcester, MA 01610, United States

The synthesis and characterization of a library of thiophene based diamine ligands will be presented. The ligands are synthesized by sequential reductive aminations. Both the electrochemical properties and reactivity with transition metals of these ligands will be reported.

CHED 725

Synthesis and oxidation studies of a copper complex with a tris-oxime ligand

Ryan T. O,Connor,, Craig M. Davis.Department of Chemistry, Xavier University, Cincinnati, OH 45207-4221, United States

Nickel and copper are not typically employed in oxidation catalysts due to the inaccessibility of higher oxidation potentials. However, electron-donating ligands can reduce the oxidation potential, thereby allowing oxygen activation. Baldwin and coworkers have synthesized nickel(II) complexes with ligands containing three oxime functional groups, specifically tris(1-propan-2-onyl oxime)amine (H3TRISOX).

Previously, our group increased the steric bulk of H3TRISOX by substituting the three methyl groups with phenyl groups to form the H3TRIPHOX ligand. The Ni- H3TRIPHOX complex was synthesized, but oxidation studies were inconclusive. This study focuses on the copper complex. Oxidation tests were performed by deoxygenating a solution of Cu(H3TRIPHOX)(H2O)2 in a primary alcohol, then adding three equivalents of NaOH. The volatile components were vacuum distilled from the catalyst. Each trial was qualitatively assessed using 1H-NMR spectroscopy, which revealed the presence of the corresponding aldehyde. Gas chromatography was then used to quantify the number of catalytic turnovers.

CHED 726

Synthesis and complexation of 1-hydroxy pyrazole

Brian Eakin,, Peter Baran.Department of Chemistry, Juniata College, Huntingdon, Pennsylvania 16652, United States

The heterocyclic compound 1-hydroxypyrazole was synthesized and studied as a ligand in transition metal complexes. The ligand was synthesized from pyrazole by oxidation with m-chloroperoxybenzoic acid as outlined by Begtrup and Vedsø. The purity and identity of the resulting crystalline product was confirmed using NMR and IR. Subsequently, complexation reactions with the first row transition metal salts were studied. Progress on complexation of 1-hydroxyl pyrazole and characterization of isolated complexes will be presented.

Begtrup, M.; Vedsø, P. J. Chem. Soc. Perkins Trans. 1. 1995, 243-247

CHED 727

Synthesis of a tridentate pyridone pincer ligand

Jacquelyn Ketner,, Alexandra Sullivan, Hannah Whittemore, B. Scott Williams.Keck Sci. Dept., Claremont Colleges, Claremont, CA 91711, United States

A tridentate pyridonate ligand has been synthesized in a six step synthesis, beginning with diethyl oxalate ($44/kg). A double Clasien condensation followed by a ring closing ammoniation affords diethyl chelidamate. The phenol is protected by iodomethane, followed by a one-pot reaction involving reduction to a diol, tosylation and amination with diethyl amine It is anticipated that the resultant tridentate pyridone ligand, 2,6-bis(diethylaminomethyl)-4-pyridone will be highly pi-basic, and should promote C-H activation in platinum group metals, as suggested by preliminary DFT calculations.

CHED 728

Investigating the photocatalytic activity of mixed metal oxides with SHArK and SEAL to generate hydrogen from water

Elizabeth A. Amoline, Benjamin R. Hellner-Burris, Evan M. Krizon, Nicole L. Zovack, Christopher M. Stanisky, G. Rattan K. Khalsa.Department of Chemistry, Thiel College, Greenville, PA 16125, United States

Electrolysis of water produces hydrogen, which has immense potential as a clean, renewable fuel. Radiant energy from the sun could drive the electrolysis, assuming a suitable photocatalyst is identified. In this work, combinations of mixed metal oxides have been tested, with the goal of finding materials with suitable band gaps and band positions for the photoelectrolysis of water with visible radiation. Two inexpensive systems have been employed: SHArK (Solar Hydrogen Activity Research Kit) and SEAL (Solar Energy Activity Lab). One utilizes a green laser pointer as a light source and the other employs an array of LEDs. These systems allow efficient analysis of photocurrents generated by various multicomponent metal oxides. Results from the two methods will be compared for promising combinations.

CHED 729

Preparation of novel rhenium (I) compounds using less common diimine ligands

Calvin Luu1,, Richard S. Herrick1, Christopher J. Ziegler2, Mitchell C Shetter1.  (1) Department of Chemistry, College of the Holy Cross, Worcester, MA 01610, United States  (2) Department of Chemistry, University of Akron, Akron, OH 44325, United States

Recently 188Re, a β emitter, has started to be considered for medical use. Combining 99mTc, which is widely used in nuclear medicine, with 188Re opens up the possibility of developing related compounds for diagnostic imaging and therapy of a tumor site.

Use of organometallic compounds of technetium or rhenium as tagging agents has received much study because they can be obtained in a clinically appropriate fashion and because compounds can be prepared that withstand biological nucleophiles and that target tumor sites.

Diimines compounds of Re d6 with an appropriate sixth ligand are quite stable and can be modified for biological applications. The most common diimines are 2,2'-bipyridine, and the Schiff base adducts pyridine-2-carbaldehyde imine, and diazabutadiene.

Here we report the use of less common diimines: 2,2'-biimidazole, and 2-(2'-pyridyl)imidazole, 2-(2'-pyridyl)benzimidazole. Each of these ligands has the possibility of further modification by alkylation of an unbound amine. This could prove to be a way of attaching groups that could target a biological receptor.

We have prepared nine Re(CO)3(N-N)X compounds using these three diimine ligands and X = Cl, Br, I. Each compound is completely characterized; the structures of five compounds were elucidated by single crystal X-ray crystallography. The three diimines, which have only occasionally been used in coordination complexes, bind tightly forming stable complexes.

CHED 730

Rhenium(I) compounds bound by tripodal ligands of pyridine and N-methylimidazole

Catherine Bogdanowicz1,, Richard S. Herrick1, Christopher J. Ziegler2, Donald L. Jameson3.  (1) Department of Chemistry, College of the Holy Cross, Worcester, MA 01610, United States  (2) Department of Chemistry, University of Akron, Akron, OH 44325, United States  (3) Department of Chemistry, Gettysburg College, Gettysburg, PA 17325, United States

Technetium-99m is the most commonly used radionuclide in nuclear medicine, but has no stable nuclides. Studying cold rhenium compounds as analogs for technetium derivatives has long been a standard means of searching for radiopharmaceutical candidates. More recently, as rhenium-188 (half-life of 17 hours with β- = 2.1 MeV) becomes available carrier free, and a clinically relevant formulation becomes available for the 188Re(CO)3+ core, there is interest in theranostic treatments, where a matched pair of 99mTc and 188Re compounds would target the same location for diagnostic and therapeutic uses, respectively.

We have previously prepared novel compounds as possible target-specific radiopharmaceuticals. But we have also prepared candidates of novel metal-essential radiopharmaceuticals compounds. One avenue we've examined is the use of neutral tripodal ligands bound to Re(CO)3+ to create lipophilic compounds that will stand up to biological nucleophiles. We have previously prepared Re(CO)3+ derivatives with methane-derivatized tripodal derivatives with amine, pyrazole, imidazole and pyridine donor groups.

In the current study we present results showing that imidazole based-ligands are inferior to corresponding pyridine-based ligands as the tris-imidazole ligands often act only as k2-donors. In each case the methane-derivatized tris-2-pyridine ligand acts as a k3-donor and strongly resists replacement by biological nucleophiles.

Finally, we present new compounds with a pendant ether ligand that will help create lipophilic compounds that might have biological use.

Novel compounds were characterized by spectroscopic and crystallographic means.

CHED 731

Synthesis and characterization of water soluble salen ligand for biological testing

Kathleen A Blacksmith,, Devin McBain, Dylan Carroll, Larry Hanne, Erik Wasinger.Chemistry, CSU Chico, Chico, CA 95926, United States

The potential of Salen type ligands applicability in the medical world is increasingly being uncovered. Unfortunately, most Schiff base complexes are not water-soluble. This poses a problem for designing bioavailable drugs or pro-drugs. The water soluble ligand, Na2[5,5-sulphonatosalen], was synthesized and metalated with nickel, zinc, and copper for testing biological activity in bacteria. The syntheses and spectroscopic characteristics will be discussed.

CHED 732

Ligand-assisted proton delivery in diiron complexes as electrocatalysts for H2 production: Ligand and complex synthesis

Nicholas Zaibaq1,, Pokhraj Ghosh2, Chung-Hung Hsieh2, Marcetta Y. Darensbourg2.  (1) Department of Chemistry and Physics, University of St. Thomas, Houston, TX 77006, United States  (2) Department of Chemistry, Texas A&M University, College Station, TX 77843, United States

The active site of the enzyme diiron hydrogenase is of particular interest to inorganic chemists for its ability to catalyze the reduction of protons to form hydrogen gas. This group is interested in synthesizing biomimetic, organometallic analogs of the enzyme active site which may serve as affordable and efficient electrocatalysts of hydrogen production. This project in particular focuses mainly on synthesizing novel ligands containing a methyl and an amino group (or a substituted amino group) on the bridgehead carbon of a propanedithiolate ligand. Ligands that have been synthesized include the dithiolates SCH2C(CH3)(NH2)CH2S, SCH2C(CH3)(NBn2)CH2S, and SCH2C(CH3)(NHTos)CH2S (Bn = benzyl; Tos = tosyl). As dianions, the potential bridging ligands react to form Fe2(CO)6 complexes which have been characterized by infrared spectroscopy. The complexes containing these ligands may augment catalytic efficacy whereby the amino group acts as a “built-in” base, strategically positioned next to the catalytically active iron for proton delivery.

CHED 733

Phase transition thermodynamics of carborane-based low melting salts

Lars Soderstrom,, Max Klemes, Anna Larsen,, Ithaca College, Ithaca, NY 14850, United States

Presented project pursues development of novel low-melting ionic materials involving closo- and nido-carborane cluster anions. Thermodynamic investigation of the phase transition processes in these materials explores the correlation between the relative enthalpy and entropy contributions and the varying degree of derivatization introduced in cations and anions. The compounds are synthesized in the metathesis reactions and studied by Differential Scanning Calorimetry and X-ray single crystal diffraction methods.

CHED 734

Targeting conjugated enyne isomers via rhodium pincer catalyst advances

Shane S Galley1,, Anna S Larsen1,, Oleg. V. Ozerov2.  (1) Department of Chemistry, Ithaca College, Ithaca, NY 14850, United States  (2) Department of Chemistry, Texas A&M University, College Station, TX 77843, United States

Rhodium complexes with pincer-type ligands (PNP- and PoCoP shown below) are used to mediate the dimerization of terminal alkynes. We pursue the improvement of selectivity of the reaction for each specific enyne isomer by varying the substituents on the phosphines and on the aromatic rings of the ligands, thereby slightly changing the steric and electronic parameters of the rhodium metal center in the catalyst.

CHED 735

Microwave-assisted iodination of 1-carba-closo-dodecaborate(1-): An improved synthesis of CB11H6I6- and CB11HI11-

Paul S Chang,, Aaron J Rosenbaum, Marcus A Juhasz.Department of Chemistry, Whitman College, Walla Walla, WA 99362, United States

Hexaiodinated and undecaiodinated derivatives of 1-carba-closo-dodecaborate(1-) were prepared by microwave-assisted reactions of the closo-CB11H12- cluster. Compared to conventional heating, microwave irradiation was found to significantly reduce reaction times, and reactions were able to be performed with a milder iodinating reagent. The iodinated products, CB11H6I6- and CB11HI11-, were characterized by 11B NMR, IR, and LC-MS. Details of the synthesis of these products and a discussion of their reactivities will be presented.

CHED 736

Synthesis of ruthenium terpyridine and ruthenium bipyridine coplexes for β-methylamino-L-alanine (BMAA)

Brittany D. Bevier,, Arturo Gasga,, Melissa L. Golden.Department of Chemistry, CSU Fresno, Fresno, CA 93740, United States

Beta-methylamino-L-alanine or BMAA is a non-proteinogenic amino acid which is produced by cyanobacteria. It has been found to be a neurotoxin and linked to different degenerative brain diseases such as Parkinson's and Alzheimer's. The fluorescing ligands bipyridine and terpyridine, which have been well studied, were selected to develop ruthenium chelate sensors for BMAA. The starting materials, Ru(trpy)Cl3 and Ru(bipy)Cl2, were synthesized according to literature procedures. In order to better understand the coordination chemistry of these complexes, computational techniques were used first to predict how BMAA may bind to Ru(trpy)Cl3 and Ru(bipy)Cl2. Before adding the BMAA•HCl to the ruthenium complexes the acid is neutralized, and the UV-vis spectrum of Ru(bipy)2Cl2 in ethanol shows a blue shift of the two maxima when BMAA binds. Synthetic and computational results will be presented in further detail.

CHED 737

Synthesis of benzoylpyridine-thiosemicarbazone ligands and their copper and palladium complexes: Analysis of their anti-proliferative properties

Jenny Conner,, Margarett Holder, Amanda Werlein, Edward C Lisic.Department of Chemistry, Tennessee Technological University, Cookeville, TN 38505, United States

Our research is centered around the anti-proliferative properties of benzoylpyridine-thiosemicarbazone ligands and their accompanying Cu2+ and Pd2+ metal coordination complexes. In order to begin our study, we first synthesized several different BZP-TSC ligands, saving some for our studies and reacting the remainder with metal ions. After obtaining these compounds, we then put the compounds we had synthesized through a series of bacteria studies, using the MIC (minimum inhibitory concentration) methods to test the activity of the compounds.

CHED 738

Series of alloxan thiosemicarbazones: Structures and reactions with copper (II)

Margarett Holder,, Talon Hill, Edward C Lisic.Department of Chemistry, Tennessee Technological University, Cookeville, TN 38505, United States

This work demonstrates the synthesis of a series of seven alloxan thiosemicarbazone compounds, and the x-ray crystal structure of one of them, the alloxan tert-butylthiosemicarbazone. The alloxan substrate was reacted with thiosemicarbazide, 4-methyl-3-thiosemicarbazide, 4-ethyl-3-thiosemicarbazide, 4-tert-butyl-3-thiosemicarbazide, 4-benzyl-3-thiosemicarbazide, 4,4-dimethyl-3-thiosemicarbazide, and 4-phenyl-3-thiosemicarbazide to form the thiosemicarbazone ligands. These ligands act as a chelating tridentate ligands with Cu(II) when reacted with copper (II) chloride. These new metal complexes were then tested for anti-proliferative activity in a bacteria study to determine the minimum inhibitory concentrations needed to stop their growth.

CHED 739

Modification of cyclodisilazane ligands for attachment to nanogold particles and gold monolayers

Robert R. Cutler,, Ingo Schranz.Department of Chemistry, Henderson State University, Arkadelphia, Arkansas 71999, United States

The thiolation of cyclodisilazane heterocycles has been explored. It has been determined that functionalizing amido chlorosilanes prior to cyclizing them, affords the desired mercapto cyclodisilazane. The Si—Cl bond is ideal for the attachment of mercaptoethanol to the chlorosilane. Mecraptoethanol reacts selectively with the alcohol group leaving the thiol group available for potential attachment to nanogold particles. Multistep synthetic pathways leading to a number of thiolated products have been attempted. All products and intermediates where characterized by 1H-NMR spectroscopy

CHED 740

Activation of azide by rhenium cluster complexes

Angela M Howard,, Stanley A Knott, Jessica L Durham, Lisa F Szczepura.Department of Chemistry, Illinois State University, Normal, IL 61790-4160, United States

Two new rhenium cluster complexes, [Re6Se8(PEt3)5(N3)](BF4) and cis-[Re6Se8(PEt3)4(N3)2], were synthesized and characterized using 1H and 31P NMR spectroscopy, IR spectroscopy, mass spectrometry and elemental analysis. X-ray crystallographic analyses were also conducted and confirmed the structures of these new compounds. The mono and di-substituted azido complexes were then shown to react with activated alkynes such as dimethyl acetylenedicarboxylate (DMAD), to form triazolate complexes. These compounds were also characterized using a variety of techniques. This presentation will cover the synthesis and characterization of the azide and triazolate cluster complexes as well as alkylation studies involving the mono-triazolate complex, [Re6Se8(PEt3)5(C6H6O4N3)](BF4).

CHED 741

Synthesis and reactivity of novel bimetallic triple-layer complexes

Elizabeth Ochoa,, Alex Watson, Sonam Ghag, Eric Watson.Department of Chemistry, Seattle University, Seattle, WA 98122, United States

A series of novel bimetallic triple-decker organometallic complexes has been prepared. Each complex has been characterized by various spectroscopic methods and its molecular structure determined via X-ray diffraction methods. Two distinct mechanisms for triple-decker formation have been observed. As an example of the first, [(η5-C5R5)Ru(NCCH3)3]PF6 (R=H,CH3) coordinated to one ring of Cp'2Fe (Cp' = tetramethylcyclopentadienyl ligand) to afford a heterobimetallic triple-decker complex ion, [(η5-C5R5)RuCp'FeCp']PF6. By a second mechanism, reaction of [(η6-naphthalene)Mn(CO)3]BF4 with Cp'2Fe brought about ring abstraction to yield Cp'Mn(CO)3 and by mass and charge balance, [Cp'Fe]BF4. The newly produced iron cation then combined with an equivalent of unreacted metallocene to give a homobimetallic triple-layer complex [Cp'FeCp'FeCp']BF4. This chemistry has been extended to Cp'2Ru and Cp'2Os and the crystal structures of [Cp'2OsCl]BF4 and Cp'2Os have been determined.

CHED 742

Microwave assisted synthesis of imide ligands and metal organic frameworks

Nicholas Traversa,, Carmen Gauthier.Department of Chemistry and Physics, Florida Southern College, Lakeland, Florida 33801-5698, United States

This poster will present the synthesis of imide ligands and metal organic frameworks (MOFs) using a microwave reactor and a conventional microwave oven. The imide ligands were used as building blocks in the synthesis of MOFs containing copper (II) ions and 4,4' bipyridine. By using microwave assisted synthesis, reaction times were significantly reduced. The reaction times for synthesis of the imide ligands were reduced from about 24 hours to somewhere between eighty seconds and thirty minutes; while the MOF reactions were completed in less than one hour. The ligands were characterized using 13C and 1H NMR and infrared spectroscopy (IR). The MOFs were characterized by IR, thermo-gravimetric analysis (TGA) and x-ray diffraction.

CHED 743

Synthesis of molybdenum imido complexes containing the ligand N-salicylidene-2-aminophenol

Severin Thompson,, Martin Minelli.Department of Chemistry, Grinnell College, Grinnell, Iowa 50112, United States

Molybdenum imido complexes have been extensively studied and synthesized due to their practical use as catalysts in several chemical reactions, as well as the unique properties of the molybdenum nitrogen bond in these complexes. The structures of molybdenum imido complexes and their sensitivity to air present several synthetic challenges. Our group has successfully synthesized several molybdenum bis(imido) complexes containing the tridentate ligand N-salicylidene-2-aminophenolate (sap). Facile synthesis of these compounds was achieved by refluxing a molybdenum bis(oxo) complex containing the sap ligand (MoO2(sap)) with an aryl isocyanate. Yields and purity of the products were further increased by modifying the reaction apparatus to maintain atmospheric pressure.

CHED 744

Synthesis and characterization of a novel porphyrin

William F. McKinney1,, Ting Yu Su1, Cynthia P. Tidwell1, Prakash Bharara1, Kenneth A. Belmore2.  (1) Department of Biology, Chemistry, and Mathematics, University of Montevallo, Montevallo, Alabama 35115, United States  (2) Department of Chemistry, University of Alabama, Tuscaloosa, Alabama 35487, United States

Porphyrins are of interest in research for their ability to carry out fast electron transfer. The newly synthesized 5,10,15,20-tetra[3,4-dibenzyloxy]porphyrin, TDBOP, was purified using silica gel column chromatography with chloroform as the eluent. The porphyrin was then characterized using 1H NMR, 13C NMR, UV-Visible and fluorescence spectroscopy. The nuclear magnetic resonance spectra confirmed the structure of the compound. The UV-Vis absorption spectrum of TDBOP shows characteristic spectral patterns similar to those of tetraphenyl porphyrin, with a Soret band at 424 nm and four Q bands at 519, 557, 592, and 650 nm. A Beer's Law study was carried out to determine the extinction coefficients at each of these wavelengths. They were found to be 3.9x104M-1cm-1 (424 nm), 1.6x103M-1cm-1(519nm),1.1x103M-1cm-1(557nm), 5.3x102M-1cm-1(592nm), and 5.0x102M-1cm-1(650nm). Excitation at 424 nm gave an emission at 654 nm. The manganese and copper complexes of this porphyrin have been synthesized and are currently undergoing characterization.

CHED 745


CHED 746

Mo(VI) complexes synthesized with 1,2-bis(2-hydroxyanilino)ethane

Michaela R Carlson,, Martin Minelli.Department of Chemistry, Grinnell College, Grinnell, Iowa 50112, United States

The synthetic method for the tetradentate ligand 1,2-bis(2-hydroxyanilino)ethane (L1 H2) was further optimized by an increase in reaction time to produce a yield of 90-93%. MoO2L1 was also successfully synthesized, with a yield of 81%, from a ligand substitution reaction with MoO2(acac)2 and L1 H2. Crystals of the MoO2L1 were analyzed with a Bruker X2S diffractometer and yielded a crystal structure. This complex is a distorted octahedron; the nitrogens from L1 are located trans to the terminal oxo groups. During the summer of 2012, it was also determined that while most Mo(NAr)2 complexes can be synthesized via two methods, reacting an isocyanate with MoO2L1 at 150oC or reacting Mo(N,2,6-diisopropylphenyl)2dme with Na2L1 at -78oC, Mo(NAr)2L1 solutions are temperature sensitive. Thus, only the latter reaction yielded product in low yields; however, the solid Mo(NAr)2L1 is not temperature sensitive.

CHED 747

Electrochemical trace analysis of simazine

Angela M Wieland,, Jay H Brown.Department of Chemistry, Southwest Minnesota State University, Marshall, Minnesota 56258, United States

Simazine is a common broad-leaf and annual grass herbicide used worldwide. It was deemed unsafe by the Environmental Protection Agency but has since acquired its Reregistration Eligibility Decision in 2006. Using Differential Pulse Voltammetry to analyze simazine, a 100mL stock solution of 2.0241*10-4M is prepared with 0.0040g of simazine in methanol. A buffer solution made with 1L of 0.1M Na2SO4 and H2SO4 is added drop wise until pH is 1.20. 10mL of the buffer is pipetted into a sample holder and 10μL of the simazine standard is added after each scan of DPV. After five scans, the detection limit is calculated to be 1.0771*10-7M, or 0.0213ppm. The oral Median Lethal Dose of simazine is > 5g kg-1, or 5000 ppm. The advantages of DPV to monitor contamination levels in water are (1) its low cost, (2) its simplicity, and (3) its effectiveness in detecting trace amounts of compound in solution.

CHED 748

Synthesis of boron-centered heteroscorpionates by metathesis reactions of LiTp* with heterocycles

Elisabeth L. Collins, ECOLLINS1@CUB.UCA.EDU, Richard M. Tarkka, Patrick J. Desrochers.Department of Chemistry, University of Central Arkansas, Conway, AR 72035, United States

Our previous work showed that one of three equivalent pyrazole rings of the scorpionate KTp* can be replaced with a benzotriazole ring. The goal of this study is to determine the generality of the metathesis method for the synthesis of boron-centered heteroscorpionate ligands. The variables being investigated include the counterion (K+ vs. Li+), solvent (DMF vs. toluene), and incoming aromatic ring (benzotriazole vs. 1,2,3-triazole, 1,2,4-triazole and 2-mercapto-1-methylimidazole). When the incoming ring is 1,2,3-triazole, the resultant LiTp'' ligand forms cis and trans isomers of the form L2Ni, where L = Tp'', when reacted with NiSO4. Analogous studies, which use different incoming heterocycles, and in which the L2Cu complexes were synthesized, will also be reported.

CHED 749

Utilization of solid carbon dioxide as the purge gas in the preparation of dicarbonyl(η​5​-methylcyclopentadienyl) triphenylphosphinemanganese

Dominic J. Malone,, Alexander C. Taormina,, Sara E. N. Hayik.Department of Natural Science, DeSales University, Center Valley, PA 1803.4, United States

Solid carbon dioxide was utilized as the purge gas, in place of the typical nitrogen gas method described in previous methods, in the preparation of dicarbonyl(η5-methylcyclopentadienyl)triphenylphosphinemanganese through photochemical substitution of carbonyl ligands of methylcyclopentadienyl manganese tricarbonyl with triphenylphosphine. Utilization of this method resulted in high yields being obtained after one week of UV exposure. FTIR was used to identify the product and none of the less desired disubstituted product, a known product of the traditional method, was detected. The application of this method is highly beneficial for small academic institutions where access to multiple nitrogen gas lines can be limited. Use of this method is ideal since this method produces results similar to those reported in previous sources and allows for discussion of photochemical synthesis techniques.

CHED 750

Synthesis and properties of a nickel(II) complex of 1,3-bis(2-formylphenylthio)propane oxime

Marina Solomos,, Michael J Prushan.Department of Chemistry and Biochemistry, La Salle University, Philadelphia, PA 19141, United States

The ligand, 1,3-Bis(2-formylphenylthio)propane oxime was synthesized from the reaction of 1,3-propanedithiol and o-nitrobenzaldehyde in warm DMF and subsequent reaction with hydroxylamine. The ligand belongs to a class of dithioether-dioxime ligands which have been extensively utilized for their ability to form a variety of complexes with Ni(II), including both polynuclear and mononuclear species. This ligand is first to incorporate an aromatic ring into the ligand backbone structure, which influences the structural, spectroscopic and electrochemical properties of the resulting Ni(II) complex.

CHED 751

Chemical tuning of the charge transfer characteristics of Zn(II) polypyridyl thiol complexes

Marja E Mundy,, Durwin R Striplin.Department of Chemistry, Davidson College, Davidson, North Carolina 28035, United States

Zinc(II) polypyridyl thiol complexes in the solid state have been proven to exhibit interesting ligand-to-ligand charge transfer properties, but typically, under rather high energy excitation. Utilizing quantum computations, new molecules were designed and then synthesized exhibiting absorption and charge-transfer characteristics more in the visible region of the spectra.
The electron acceptor polypyridyl ligand most used was the 2,2'-biquinoline with a variety of electron donor aromatic thiol ligands. These complexes were characterized by UV-Vis, NMR, and various optical spectroscopies.

CHED 752

Synthesis, characterizations, and fluorescence, DNA-binding, and cytotoxicity studies of rhenium(I) naphthalene-2-sulfonato complexes, fac-(CO)3(α-diimine)ReONs (ONs = naphthalene-2-sulfonate)

Dipak Giri,, Santosh K Mandal.Department of Chemistry, Morgan State University, Baltimore, Maryland 21251, United States

Tricarbonylrhenium(I)(α-diimine) complexes are of importance because they exhibit fluorescence and act as anticancer agents. A wide variety of such rhenium complexes with ligands such as chloro, pentyloxo, pentylcarbonato, p-toluenesulfonato, perrhenato, and acetylsalicylato ligands have been synthesized from our laboratory. Recently we have synthesized a series of naphthalene-2-sulfonato complexes from the reactions of the corresponding pentylcarbonato complexes with naphthalene-2-sulfonic acid (HONs) according to eq. 1:

fac-(CO)3(α-diimine)ReOC(O)OC5H11 + HONs → fac-(CO)3(α-diimine)ReONs + C5H11OH + CO2(1)

Characterization of the complexes through IR, NMR, and X-ray crystal structure determinations will be presented. Also the fluorescence properties, DNA-binding studies, and anticancer properties of the complexes will be discussed.

CHED 753

Synthesis and characterization of 1,4,7-triazacyclononane (tacn) based Rh(III) metallointercallators

Haylie L. Hancock,, Steven C. Haefner.Department of Chemistry, Bridgewater State University, Bridgewater, Massachusetts 02324, United States

Barton and co-workers previously established that the macrocyclic amine complex Rh(cyclen)(phi)3+ (cyclen = 1,4,7,10-tetraazacyclododecane, phi = 9,10-phenanthrenequinone diimine) exhibits site specific DNA binding in the major groove for GC base pairs. Building on this elegant work, our group is designing a set of novel intercalating complexes using the ancillary ligand 1,4,7-triazacyclononane (tacn) that potentially exhibit similar DNA binding properties. Replacement of cyclen with tacn creates an open metal coordination site that can be used to attach additional supporting ligands. This gives us the opportunity to modulate the DNA binding strength and specificity. Reaction of RhCl3 hydrate with tacn followed by treatment with silver triflate produces [Rh(tacn)(H2O)3][SO3CF3]3 in good yield. This compound reacts with dppz (dppz = dipyridophenanzine) to form a complex tentatively identified as Rh(tacn)(dppz)(H2O)3+. Details of the synthesis and characterization of this new potential metallointercalator will be presented along with our attempts to prepare the analogous phi complex, Rh(tacn)(phi)(H2O)3+.

CHED 754

Synthesis and reactivity of a macrocyclic binuclear cobalt catalyst: Sequestration of CO2 as a mineral carbonate

Jonathan Keim,, Carrie Poe, Elky Almarez, Patrick Farmer.Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798, United States

The synthesis and characterization of a hexadentate macrocyclic Schiff-base ligand BMXD, and a novel sulfur analogue, BMXD-S, is reported. The BMXD and the BMXD-S ligands were synthesized in good yield and characterized using NMR, mass spectrometry, and elemental analysis. It has been observed that binuclear cobalt BMXD and BMXD-S complexes catalyze the conversion of atmospheric carbon dioxide to carbonate salts. Manometer measurements of CO2 uptake from headgas above a solution of the Co2BMXDadduct at 25 oC and 1 atm of CO2 gave a turnover frequency of 0.727 min-1; analogous measurements for Co2BMXD-Sadduct obtained a turnover frequency of 0.224 min-1. A product of the uptake reaction, Co2BMXD(CO3)3 has been characterized using elemental analysis, IR, mass spectrometry and single crystal x-ray diffraction. The sulfur analogue, Co2BMXD-S(CO3)3 has been characterized by elemental analysis and IR.

CHED 755

Building an automated crystal growth chamber

Chase L. Bouchillon,, Joshua Williams.Department of Chemistry, Union University, Jackson, Tennessee 38305, United States

An automated crystal growth chamber was constructed. The chamber is under software control which gives the user the ability to have precise temperature control over the growth solution and initialize key sequences in the crystal growth process from a computer. A major consideration in the design of the system was to build the chamber using materials that would not contaminate the growth solution. This is so that unwanted crystal growth does not occur and impurities do not develop upon the crystal itself due to other ions in solution. Seed crystals were grown using homogeneous nucleation to provide a surface for heterogeneous nucleation to occur in the growth solution. Using seed crystals, high quality potassium dihydrogen phosphate (KDP) crystals were grown without unwanted homogeneous nucleation inside the chamber. The chamber will be used to grow dye inclusion crystals in order to study the interactions between certain organic dyes and inorganic crystals.

CHED 756

Synthesis and characterization of biomimetic models of multi-copper active sites

Haosen Wang,, T. Nicholas Jones, Brian J. Johnson.Department of Chemistry, College of St. Benedict | St. John's University, St. Joseph, MN 56374, United States

The research project involves the synthesis of a ligand that will serve as a model for the oxygen reducing trinuclear active sites found in multi-copper oxidases, such as laccase and ceruloplasmin. We selected a potential ligand, 1,3,5-tri(2-pyridylmethyltriazole) -2,4,6-triethyl benzene, abbreviated Ltapma, to be the ligand scaffold for this research to bind with three Cu(I) ions and then to bind with oxygen molecules. Our immediate goal for this research is to synthesize and purify the proposed ligand, and bind it to Cu(I) ions to obtain the structure of the tri-copper complex. The reaction of this complex with oxygen will also be explored. By studying these structures, we hope to gain insight into the binding motif of oxygen in these enzymes, which may lead to a better understanding of their functions.

CHED 757

Redox reactions of a Schiff-base copper(II) complex

Michelle Leatherwood1,, Victoria Lim1, Kent Evans2, Jeanette A Krause3, Justin Stace1.  (1) Department of Chemistry and Physics, Belmont University, Nashville, Tennessee 37212, United States  (2) Department of Math and Science, MidAmerica Nazarene University, Olathe, Kansas 66062-1899, United States  (3) Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States

A mononuclear Cu(II) complex, [CuLN4](ClO4)2 (LN4 = N,N'-bis-(1-pyridin-2-yl-ethylindene)-propane-1,3-diamine) has been synthesized and characterized for potential application as an enzyme mimic. The ligand was synthesized via a condensation reaction, the metal center bonded to the nitrogens as a Lewis acid; and pure product was obtained from evaporation of a concentrated acetonitrile solution. The blue crystalline product was characterized by FTIR and X-ray crystallography. The electronic spectroscopy in aqueous solution showed strong absorbance in the UV and the expected low-energy band (λmax = 620 nm, ε620 = 100 M-1cm-1). The complex is unreactive toward strong oxidants in both aqueous (HCl, HNO3) and organic (CH3I in acetonitrile) solutions, but reacts with a reductant (oxalic acid) in water. The proposed rate law of the reaction with oxalic acid and possible mechanisms will be presented. The thermodynamic parameters of the equilibrium state are also presented.

CHED 758

Synthesis of tungsten disulfide nanomaterials from tungsten alkoxides

Clifford D Hardy2,, Bernadette A. Hernandez-Sanchez1, Sarah A Hoppe1, Timothy J. Boyle1.  (1) Advanced Materials Laboratory, Sandia National Laboratories, Albuquerque, New Mexico 87106, United States  (2) Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States

Solution routes to nanoscaled tungsten chalcogenides are of interest for catalysts, lubricants, solar, and battery applications. Recently we developed a general solution route to metal chalcogenide nanomaterials from metal alkoxides (cadmium & alkaline earths) and have extended it to include the WEx. Tungsten disulfide (WS2) nanomaterials are accessible through a solvothermal reaction between tungsten (V) ethoxide and hexamethyldisilathiane. TEM/PXRD of the as prepared materials revealed monolayered WS2. Thermal treatment, under an inert atmosphere, formed bulk WS2. Full details on the synthesis and characterization will be discussed. This work was supported in part by The University of New Mexico's Nanoscience & Microsystems REU Program and by the Laboratory Directed Research and Development (LDRD) program at Sandia. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

CHED 759

Synthesis and characterization of di-3-pyridyl-formamidine and di-pyrazyl-formamidine: Potential new ligands for the formation of polymetallic networks

Joseph M Matta,, Steven C Haefner.Department of Chemical Sciences, Bridgewater State University, Bridgewater, MA 02325, United States

Metal-organic frameworks (MOFs) consist of metal ions and organic molecules that are assembled into rigid 3-dimensional networks. The resulting network structures offer a wide range of potential application including gas storage, chemical sensing, drug delivery, solid-state catalysis, and selective chemical filtering. The vast number of possible ligand-metal combinations gives rise to great variability in MOF synthesis. We have successfully prepared and characterized two novel organic ligands that may be used to synthesize new MOF materials: di-3-pyridyl-formamidine (3-HDpyF) and di-pyrazyl-formamidine (HDpyzF). These molecules feature diametrically opposed metal binding regions. The formamidinate binding region is known to support dimetal centers, while the nitrogen donors of the pyridyl and pyrazyl groups are expected to coordinate with additional metal ions thereby forming a 3-dimensional network. We are currently investigating the coordination chemistry of these novel ditopic ligands. The synthesis and characterization for 3-HDpyF, HDpyzF, and their associated metal complexes will be presented.

CHED 760

Synthesis and characterization of [Ru(tacn)(dppz)(H2O)]2+: A new potential metallointercalator

Minh V Pham,, Steven C Haefner.Department of Chemical Sciences, Bridgewater State University, Bridgewater, MA 02325, United States

Our group is interested in developing new metal based complexes capable of binding DNA through intercalation. Metal complexes that bind DNA have the potential to act as chemical probes, inhibit DNA binding proteins, and photochemically repair or excise DNA lesions. We are currently focusing on the use of 1,4,7-triazacyclononane (tacn) as a supporting ligand for octahedral metallointercalators. This ligand allows for an open coordination site that can be modified to change the DNA binding strength and specificity. To this end we have prepared the potential metallointercalator [Ru(tacn)(dppz)(H2O)][SO3CF3]2 (dppz = dipyridophenazine) in a two step procedure from RuCl3 hydrate. Reaction of RuCl3 hydrate with tacn in dmso produces [Ru(tacn)(dmso)2Cl]Cl. This compound is refluxed with dppz in water and then treated with silver triflate to remove the chloride ions and to form [Ru(tacn)(dppz)H2O][SO3CF3]2 in good yield. Details of the synthesis, characterization, and preliminary DNA binding studies will be presented.

CHED 761

Towards group two metal alkoxides and aryloxides using hydrothermal synthesis

Kayla Ryan,, Marites A. Guino-o.Department of Chemistry, University of St. Thomas, Saint Paul, Minnesota 55105, United States

Alkaline earth metal ions are known for their electrostatic interactions with ligands in aqueous media. This makes prediction of their coordination numbers a challenge when attempting to strategically synthesize coordination polymer networks or metal-organic frameworks (MOFs). Herein, we report our attempts and challenges in systematically synthesizing group two MOFs with alkoxides and aryloxides utilizing hydrothermal synthesis.

CHED 762

Different binding modes of Ni(II) and Cu(II) to the bacterial siderophore desferrioxamine B in seawater-like solutions

Kailee Potter2,, Johan Schijf1, Emily Christenson1.  (1) University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, Solomons, Maryland 20688, United States  (2) Department of Chemistry, Computer Science, and Mathematics, Adams State University, Alamosa, Colorado 81101, United States

Microorganisms secrete siderophores to facilitate uptake of Fe(III), a scarce yet essential nutrient. Siderophores are capable of binding metal ions other than Fe3+. We used desferrioxamine B as a representative siderophore and determined stabilities of its complexes with Cu2+ and Ni2+ in NaClO4 solutions at seawater ionic strength. Stability constants for Ni(II), log β1, log β2, and log β3 were found to be 4.65±0.04, 7.72±0.03, and 9.76±0.07, respectively. For Cu(II), log β1 and log β2, were determined to be 7.86±0.06 and 13.09±0.04, respectively, but log β3 could not be resolved from titration data, indicating that a hexadentate complex does not form. The tetradentate complex is about 5 orders of magnitude more stable for Cu(II) than for Ni(II). Modeling with MINEQL suggests that, in seawater, organic complexes with the observed stabilities would not contribute to the speciation of these metals at free ligand concentrations of less than 10–100 pM.

CHED 763

Synthesis and characterization of cobalt phosphate and cobalt lithium phosphate thin films from the prompt condensation of aqueous precursors

Nam Nguyen,, Daniel Hawley,, Chase Magee, Colby L Heideman.Department of Chemistry and Biochemistry, Eastern Oregon University, La Grande, OR 97850, United States

Cobalt phosphate and cobalt lithium phosphate thin films were prepared by spin casting aqueous precursor solutions onto silicon substrates. The influence of the dehydration temperature was studied by systematically increasing the soft bake temperature between deposition cycles. In cobalt lithium phosphate films two methods were used to control the cation ratio present in the films. One series of samples was prepared by spin casting alternating layers of cobalt phosphate and lithium phosphate solutions. The ratio of cobalt phosphate to lithium phosphate layers was varied in order to control the cation ratio. In the second series, the two precursor solutions were mixed in varying ratios before spin casting. In each case, the final film compositions were examined by etching the films with nitric acid and using atomic absorption spectroscopy to measure the concentration of the cobalt and lithium metals.

CHED 764

P-31 DOSY NMR evidence for oligomer formation by transition metal substituted polyoxometalates in nonpolar solvents

Adam Dannenhoffer,, Nicholas Pantano, Steven Szczepankiewicz, Mariusz Kozik.Chemistry and Biochemistry, Canisius College, Buffalo, NY 14208, United States

Our recent work demonstrated that structures of Transition Metal Substituted Heteropoly Tungstates, TMSHT, in nonpolar solvents are more complex than published in the literature. Phase transfer of TMSHTs, which is accomplished by mixing the potassium salt of TMSHT in water with tetraheptylammonium bromide in toluene, also causes some KBr to be transferred into the toluene phase. Characteristic 31-P NMR signal are attributed to the presence of the K+ and Br- ions interacting with TMSHPTs in toluene solution. However, even after the quantitative removal of potassium and bromide ions, new 31-P NMR data at low temperature (low water contents) indicate that another phenomenon takes place. In a nonpolar solvent two or more TMSHT anions join together through oxide bridges, and more NMR signals appear. 31-P NMR DOSY spectrum indicates the presence of species with larger diffusion coefficients (lower molecular weight) in wet toluene and species with smaller diffusion coefficients (greater molecular weight) in dry toluene for Zn-substituted Keggin anion.

CHED 765

Investigation of the roles of several iron(II) chelators in the release of iron from ferrioxamine B via reduction by NADH

Julia Bair,, Kassy A Mies.Department of Chemistry, Meredith College, Raleigh, NC, United States

Iron is the fourth most abundant element on earth; however, most iron exists in its less soluble ferrous state. Microorganisms compensate for this lack of bioavailability by producing small iron chelators called siderophores. The mechanism for the release of iron from siderophores has yet to be completely understood because iron-siderophore complexes are very stable. Previous studies demonstrate that iron can be released from the iron-siderophore, ferrioxamine B, through formation of a ternary complex between ferrioxamine B and the iron(II) chelator, BPDS, in the presence of reducing agents ascorbic acid, glutathione, or NADH. Preliminary evidence suggests that NADH can directly reduce iron(III) to iron(II) in ferrioxamine B in the presence of BPDS. Here, we investigate the release of iron from ferrioxamine B through direct reduction by NADH in the presence of several iron(II) chelators, including phytic acid and TPEN, which are not expected to be capable of forming a ternary complex.

CHED 766

Synthesis, fluorescence properties, DNA-binding studies, and anticancer properties of tricarbonylrhenium(I)(α-diimine) picolinato and nicotinato complexes

Brent V Powell,, Santosh K Mandal.Chemistry, Morgan State University, Baltimore, Maryland 21251, United States

Tricarbonylrhenium(I)(α-diimine) complexes of the type, fac-(CO)3(α-diimine)ReX, where, X is a monodentate ligand, are important because such complexes possess fluorescence and antitumor properties. Previously many of these complexes have been synthesized from our laboratory. Recently we have synthesized a series of picolinato and nicotinato complexes from the reactions of the corresponding pentylcarbonato complexes with picolinic and nicotinic acid respectively, according to eq. 1:

fac-(CO)3(α-diimine)ReOC(O)OC5H11 + HOZ → fac-(CO)3(α-diimine)ReZ + C5H11OH + CO2(1)

(HOZ = picolinic or nicotinic acid)

We would like to present the characterizations of the picolinato and nicotinato complexes through IR, NMR, and X-ray crystal structure determinations. Also the fluorescence properties, DNA binding studies, and anticancer properties will be presented.

CHED 767

Steric effects on the formation of -oxo-centered nickel(II) hexamers

Alex Confer,, Michael J Prushan.Department of Chemistry and Biochemistry, La Salle University, Philadelphia, PA 19141, United States

A series of thioether-oxime ligands has been prepared from chloroacetone oxime and 3-chloro-3-methylbutanone oxime. Thiolates with varying degrees of steric bulk (ethyl-, isopropyl-, tert-butyl-, napthyl-, and 2-(diethylamino)ethyl-) have been employed, allowing us to observe steric restrictions in the self-assembly of a µ-oxo-centered nickel(II) hexamer. Mass spectral and crystallographic evidence suggest that moderately-hindered, chloroacetone oxime-derived ligand systems tend preferentially towards hexanucleation, while more severely-hindered 3-chloro-3-methylbutanone oxime derivatives do not. Moreover, we have found that steric limitations in the R-group of the thioether also affect self-assembly, insofar as the napthyl thioether “turns off” hexanucleation while the 2-(diethylamino)ethyl thioether favors it. UV-visible, structural, and magnetic data are discussed.

CHED 768

Investigation of ligand exchange between Fe(III), In(III), and Ga(III) dithiocarbamate complexes using 1H NMR

Matthew Logan,, Kevin Roy, Norman V. Duffy, James E. Coffield.Department of Chemistry, Wheeling Jesuit University, Wheeling, WV 26003, United States

Dialkyldithiocarbamate complexes of Fe(III), In(III), and Ga(III) are labile and freely interchange ligands. Proton NMR has been used in previous studies to investigate the exchange of ligands between tris(diethyldithiocarbamato)iron(III) and tris(dibenzyldithiocarbamato)iron(III). The CH2 protons on the ethyl and benzyl substituents are significantly shifted (30 to 40 ppm) due to their proximity to the paramagnetic Fe(III). Though broadened, these peaks are sufficiently separated to determine the relative amounts of the mixed ligand complexes. The distribution of the ligands matches the statistically expected proportions. This study uses proton NMR to study the distribution of these two ligands between paramagnetic Fe(III) and either diamagnetic In(III) or Ga(III). Deviations from statistically expected ratios provide a measure of the preference of Fe(III) for the two different ligands relative to In(III) (or Ga(III)) since they are in competition with one another.

CHED 769

Analysis of the thermal decomposition of several cis-dicarbonylbis(diorganodithiocarbamato)iron(II) complexes

Cassandra Crihfield,, James E. Coffield, Norman V. Duffy.Department of Chemistry, Wheeling Jesuit University, Wheeling, WV 26003, United States

Metal dithiocarbamates are complexes of metal ions and the uninegative dithiocarbamate ligand. The properties of these complexes are dependent on the identity of the metal ion and the nature of the organic substituents on the dithiocarbamate ligand. Previous work in the WJU chemistry department involving thermal removal of one of the carbonyl ligands from cis-dicarbonylbis(methylphenyldithiocarbamato)iron(II) has suggested the possibility of a stable monocarbonyl compound. Successful synthesis of monocarbonyl-bis(diorganodithiocarbamatoiron(II) compounds has not been reported in the literature. This research investigates the synthesis of these monocarbonyl complexes from several cis-dicarbonylbis(diorganodithiocarbamato)iron(II) compounds using a thermogravimetric analyzer. Thermogravimetric analysis is used to determine the synthesis temperatures of the monocarbonyl complexes, as well as the stability of the products in nitrogen and air.

CHED 770

Differential scanning calorimetry of the thermal decomposition of several cis-dicarbonylbis(diorganodithiocarbamato)iron(II) complexes

Andre Lamyaithong,, Norman V. Duffy, James E. Coffield.Department of Chemistry, Wheeling Jesuit University, Wheeling, WV 26003, United States

The preparation and infrared spectrum of cis-dicarbonylbis(dimethyldithiocarbamato)iron(II) derivatives were first reported by Cotton and McCleverty. Previous work at Wheeling Jesuit University has indicated the presence of stable intermediates produced during the thermal decomposition of cis-dicarbonylbis(diorganodithiocarbamato)iron(II) complexes. In particular, evidence suggests the possible formation of the monocarbonylbis(diorganodithiocarbamato)iron(II) complexes through the thermal loss of one of the carbonyl ligands. The successful synthesis of this class of compounds has not been previously reported in the literature. Differential scanning calorimetry (DSC) allows us to measure the energy changes associated with the loss of carbonyl ligands as well as other decomposition processes. Correlating these energy changes with the nature of the organic substituents on the dithiocarbamate ligands will add to the understanding of the impact of those substituents on the bond dissociation energy of the carbonyl ligand.

CHED 771

Nickel complexes with N2OS2 and N2O2S2 ligands

Amanda Huseby,, Sarah King,, Jason J Smee, of Chemistry, The University of Texas at Tyler, Tyler, TX 75799, United States

The synthesis of nickel complexes with dithiolate derivatives of 3-hydroxy-1,5-diazacyclooctane and 3,7-dihydroxy-1,5-diazacyclooctane will be discussed. The complexes will be characterized in the solid-state and in solution. The effects of pH on the structure and stability of the complexes will be shown. Preliminary reactivity studies of these metal complexes towards oxygenating species and alkylating agents in the presence of the pendant hydroxyl group will also be presented.

CHED 772

Syntheses and structures of vanadium(IV) and (V) thiolate complexes

Patrick R Martin,, Brody Snyder,, Jason J Smee, of Chemistry, The University of Texas at Tyler, Tyler, TX 75799, United States

The synthesis of the V(IV) and V(V) complexes of mercaptomethylpropyl-1,5-diazacycloheptane are reported. Non-aqueous techniques were utilized to prepare the V(V) complex due to the tendency of V(V) to undergo reduction in the presence of thiolates. The V(IV) complex is more stable and exists as a dimeric, dicationic species. The characterization of the complexes in the solid-state and in solution will also be presented.

CHED 773

Discussion on one specific case in VSEPR: WH6

Chenxi Zhang,, Xuefeng Wang.Department of Chemistry, Tongji University, Shanghai, China

The Valence shell electron pair repulsion (VSEPR) model provides a useful basis for understanding and molecular geometry. Thus, it is worthwhile understanding of its physical basis. One very interesting specific case of VSEPR model: WH6 will be provided and the factor that controls the “non-VSEPR” structure will be discussed in detail. At last, the comparison between the molecular structure of WH6 and WF6would promote our understanding of bonding between “non-VSEPR” and VSEPR molecule. Here we attempt to provide this paper based on the following main parts: 1) The Pauli principle is the physical basis of the VSEPR model; 2) The metal d orbital participation in σ bonding is an important factor controls the distorted metal complexes; 3)Ligand electrostatic repulsion disfavors the “non-VSEPR” arrangements especially when the ligand has more negative charge or non-bonding electron pairs.

Fig 1. the C3v structure of WH6

Fig 2. the Oh structure of WF6

CHED 774

Synthesis and characterization of low melting point SnF2-SnO-P2O5 glasses

Tristan Harper1,, James York-Winegar2, Carrie Brennan1, Justin Oelgoetz2, Andriy Kovalskyy2.  (1) Department of Chemistry, Austin Peay State University, Clarksville, Tennessee 37040, United States  (2) Department of Physics, Austin Peay State University, Clarksville, Tennessee 37040, United States

Low melting point glasses have recently received attention as a successful host matrix to rare earth metals and organic elements to be used in energy conversion for solar devices. It is known that said glasses usually have insufficient environmental durability. Recent studies have shown that the tin phosphate glasses have both the ability to effectively accept rare earth elements while still maintaining low reactivity. A set of SnF2-SnO-P2O5 phosphate glasses of different compositions and high optical quality have been prepared using conventional melting techniques. The structure of the obtained glasses was studied using a combination of Raman spectroscopy and high-resolution X-ray photoelectron spectroscopy (XPS) methods. Tentative structures have been inferred from the XPS and Raman data. The glasses were then doped with Er2O3. The produced Raman spectra were augmented from the original, concluding that the dopant materials changed the overall structure of the glass.

CHED 775

Biofuels for the undergraduate organic chemistry laboratory

Damaris Delgadillo,, Kaela Caballero, Betsy Leverett.Department of Chemistry, University of the Incarnate Word, San Antonio, TX 78209, United States

A two-part method for the preparation of biofuel from unicellular algae is presented. Neutral lipids are extracted from dried algal biomass using chloroform and methanol and transesterified at room temperature in sodium hydroxide and methanol. The experiment also includes analysis of the mixed methyl ester products by 1H NMR. This laboratory exercise is designed to exemplify aspects of carbonyl chemistry and NMR analysis in the context of the popular topic of renewable fuels from plants and algae.

CHED 776

Comparison of passivation techniques on Multiphase alloy (35% Ni)

Andrew T Wheeler,, Ken Rohly.Department of Chemistry, Bethel University, Arden Hills, Minnesota 55126, United States

The multiphase alloy MP35N, composed of 35% nickel, 35% cobalt, 20% chromium, and 10% molybdenum, is widely used in implantable medical devices. Samples were electropolished, passivated, and analyzed with DC potentiostatic cyclic polarization scans. All samples were electropolished similarly, divided into eight groups, and passivated according to the necessary conditions. These conditions investigated the impact of passivation time, temperature, and solution on the electrochemical characteristics of the samples. In all, 32 trials were completed (n = 4), and results were analyzed by design of experiments software. Passivation conditions were either 10 or 60 minutes, temperature was either 25 or 65 °C, and the solution used for passivation was either 35% nitric acid or 4% citric acid. When passivated for 60 minutes using a 65 °C nitric acid solution, the cyclic polarization scans indicated that no breakdown occurred.

CHED 777

RbNdTa 2 O7: A study in topochemical methods abstract

Lauren Elise Franklin1,, John Wiley2, Dariush Asadi.  (1) Spring Hill College, Mobile, Alabama 36608, United States  (2) Department of Chemistry and Advanced Materials Research Institute, University of New Orleans, New Orleans, LA 70148, United States

The topochemical method, ion-exchange, may be used in the

manipulation of layered, Dion-Jacobson type perovskites. In this

study, the behavior of RbNdTa2 O7 was examined for the

replacement of rubidium by a series of alkali metal cations and 3d

transition metal halides. Results were varied with the expected

outcome which was based on previous successful ion-exchange

experiments performed using perovskites composed of rare-earth

elements similar in nature to neodymium as well as experiments

performed using perovskites composed of transition metals similar to


CHED 778

Structural analysis of Bosch heated exhaust gas oxygen sensors after voltage treatments

Regina E. Blackman1,, Arwa Alshowaier2, Erica P. Murray2.  (1) Department of Chemistry, Francis Marion University, Florence, SC 29506, United States  (2) Institute for Micromanufacturing, Louisiana Tech University, Ruston, LA 71272, United States

Heated Exhaust Gas Oxygen Sensors are used to detect the emissions of the everyday vehicle. Applying a voltage to these sensors simulates the conditions that the sensor is under when in a vehicle. Experiments show that when a voltage is applied for a long enough time, blackening occurs around the electrodes. By performing voltage treatments, it is possible to define the conditions that cause blackening. It is also possible to see the changes in the structure of the Yttria Stabilized Zirconia (YSZ) by cutting the sensor and looking at it under a Scanning Electron Microscope. Looking at the cut sensor under an optical microscope allows for the design of the sensor to be examined and measurements to be taken.

CHED 779

En route synthesis of MTEP/MPEP analogs selective for mGluR5

Sean Pidgeon,, Amy Bradley.Department of Chemistry, Wilkes University, Wilkes-Barre, PA 18701, United States

MTEP/MPEP are antagonists for metabotropic glutamate receptor 5 (mGluR5) located throughout the central nervous system. This G-protein coupled receptor, upon activation by glutamate, is responsible for the influx of Ca+ resulting in various cellular responses. Excessive activation of mGlu5 receptors has shown to cause disorders such as pain, depression, anxiety, and drug addiction/withdrawal. MTEP/MPEP have shown to be potent compounds that prevent such activation and reduce the disorders. Several analogues will be synthesized that can potentially be selective for mGluR5.

CHED 780

Role of myeloperoxidase in apocynin-mediated NADPH oxidase inhibition

Carolyn M Levinn,, Michael S Azzaro,, David K Johnson.Department of Chemistry, State University of New York at Geneseo, Geneseo, NY 14454, United States

Apocynin and its dimer have been shown to be potent inhibitors of NADPH oxidase, an enzyme that produces harmful free radicals in the body. The mechanism and efficiency of inhibition has been investigated. The dimers of apocynin and two structural analogs, vanillin and 4-methyl-2-methoxyphenol, have been synthesized, and their relative inhibitory effects analyzed using LCMS and enzymatic activity assays. It has been shown that there is a logarithmic relationship between the concentration of apocynin and the percentage of inhibition, characteristic of a classic inhibition plot. LCMS data indicates that the method of inhibition involves the apocynin dimer preventing the formation of cysteine dimer link. This hinders the migration of the p47-phox subunit, which would activate the NADPH oxidase enzyme. This mechanism and inhibition data suggest that apocynin and its analogs have potential in many pharmaceutical applications, including treatment for diabetic retinopathy and Alzheimer's.

CHED 781

Manganese-porphyrin complex used as a potential radiation mitigator

Mark J. Biedka1,2,, Detcho Stoyanovsky1.  (1) Department of of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States  (2) Department of Chemistry, Westminster College, New Wilmington, Pennsylvania 16172, United States

Recent studies have shown the medicinal benefit of manganese-porphyrin complexes as radiation mitigators in mice. These studies have shown that clearance of H2O2 within the mitochondria has led to the inhibition of apoptosis, resulting in increased radiomitigative potential from irradiation with γ-rays. Although the manganese-porphyrin complex was able to clear H2O2 form the mitochondria, it failed to protect against superoxide (O2-∙) free radicals. To enhance the pharmacological effectiveness and radiomitigative potential, we tested the ability of porphyrin-Mn2+ complex to be derivatized, using HPLC, with 4-carboxy-2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), to clear O2-∙ within the mitochondria. We report that the substitution of the triphenylphosphonium functional group of the Mn2+-porphyrin complex with TEMPO yielded a pharmacologically inactive complex.

CHED 782

Molecular docking investigation of antileishmanial plant-derived coumarins

William R Erwin,, William N. Setzer.Department of Chemistry, University of Alabama in Huntsville, Huntsville, Alabama 35899, United States

Leishmaniases are diseases caused by species of the protozoan parasite, Leishmania. Leishmaniasis, like most other diseases endemic to the tropics, lacks an effective, safe, and affordable chemotherapy. A number of plant-derived coumarins have been shown to exhibit in-vitro antileishmanial or antitrypanosomal activity. Thirty-seven natural coumarins which had previously exhibited antiparasitic activity were screened in silico against potential Leishmania drug targets using a molecular docking approach, and twenty-two protein targets were examined in this study. The protein target that showed the most “hits” (i.e., the largest number of coumarin ligands that exhibited selective docking energies) was Leishmania major methionyl-tRNA synthetase. Two coumarin ligands showed remarkably strong docking to several protein targets: umbelliprenin and mammea A/AA. This in-silico molecular docking study has revealed potential biomolecular targets of plant-derived coumarins with antileishmanial activity. The results could provide the framework for synthetic modification or de novo synthesis based on this structural manifold.

CHED 783

Cytotoxicity of Juniperus virginia on MCF-7 breast cancer cells

Leah E Woodall,, Noura S. Dosoky, William Setzer.University of Alabama in Huntsville, Huntsville, AL 35899, United States

The goal of this research project was to test the ability of Juniperus virginia extracts to kill MCF-7 breast cancer cells. The species is more commonly known as the Eastern Red Cedar and is abundant in the eastern United States, which makes it a attractive natural source for anticancer chemotherapeutics. Two samples of J. virginiana were collected and extracted using a Soxhlet extractor. The leaves (needles) of male and female trees were separately extracted with refluxing chloroform. An MTT assay was used to determine if either of the samples would effect the growth of the cancer cells. Once it was determined which extract(s) would suspend the growth of these cells bioactivity-directed preparative column chromatography was used to separate and isolate individual active components. It was found that the crude chloroform extracts of the female plant and the male plant showed 61.3% killing and 64.7% killing, respectively, at 100 ug/mL. Fractionation of the crude female extract yielded four active (> 90% kill at 100 ug/mL) fractions.

CHED 784

Highly functionalized aromatics: An investigation into the synthesis and flavoprotein inhibiting properties of benzofulvene motifs

Adam C Glass, Jack Rubenkonig, of Chemistry, Pacific Lutheran University, Tacoma, Washington 98447, United States

Molecules with a benzofulvene motif were synthesized in high yield via a pseudo-condensation of phenyl indenyl lithium with substituted aryl aldehydes. In the optimization of this synthetic method, our group varied several factors including: reaction temperature, solvent, and metal stabilizing group. We then utilized quantitative NMR to determine yields via an internal standard. At present our optimized procedure has yields above 80%. We have now turned our attention towards medicinal applications of the benzofulvene motif. Utilizing protein modeling docking software, we have investigated the utility of the benzofulvene motif as a Flavoprotein active site inhibitor. We have modeled benzofulvene motifs, having determined binding affinities of up to -9.6 kcal/mole to the active site of Human Thioredoxin Reductase, an enzyme targeted in possible anti-carcinogenic pharmaceuticals. Our facile synthetic route may provide a new means of combating aggressive cancer types.

CHED 785

Role of abin 1 mutation in lupus nephritis

Rebecca Oliver1,2,, Erik Korte1, Dawn Caster1, David Powell1.  (1) Department of Nephrology, University of Louisville, Louisville, KY 40202, United States  (2) Brown Science Center, Transylvania University, Lexington, KY 40508, United States

Lupus nephritis (LN) occurs in majority of patients with systemic lupus erythematosus (SLE) and represents a major source of morbidity and mortality. Recent genome wide association studies (GWAS) of patients with SLE identified mutations in NF-κB signaling components, including A20-binding inhibitor of NF-κB 1 (ABIN1), a polyubiquitin binding protein which inhibits NF-κB activity. Preliminary findings from other study show that 2 SNPs in the ABIN1 gene (rs7708392 and rs4958881) have a strong association with LN in European-Ancestry and African American SLE patients, respectively. We have found that immortalized B cells from patients with rs4958881 have elevated levels of toll-like receptor-mediated cytokine/chemokine production as compared to wild type. We show that the ABIN1 [D485N] knock-in mice develop progressive renal function impairment and glomerulonephritis with histologic features of the most common and severe class III/IV human LN.Our results suggest that ABIN1 polymorphisms and subsequent dysfunction contributes to the pathogenesis of LN.

CHED 786

Influence of substituents on the antibiotic activity of highly substituted δ-lactones

Kyle Morgenstern,, Katie Fox,, Lee Raube, Brad Andersh.Department of Chemistry and Biochemistry, Bradley University, Peoria, IL 61625, United States

Through an unexpected condensation reaction between β-keto-esters and benzaldehydes, highly substituted 5-aryl-3-oxo-δ-lactones can be synthesized in a single-pot reaction. It has also been found that the resulting lactones exhibit antibiotic activity against both Gram-positive and Gram-negative bacteria. As a preliminary assessment of the activity of these novel compounds, antibiotic susceptibility tests (minimum inhibitory concentrations (MIC)) were performed against Bacillus subtilis, a ubiquitous soil bacteria. The effect of varying substituents on both the lactone and benzene rings was investigated. From this work it was discovered that the introduction of hydrophobic substituents on the lactone ring and electron withdrawing hydrophobic substituents on the benzene ring enhance the activity of the compounds. Results from both the synthetic efforts and the antibiotic susceptibility testing will be presented.

CHED 787

Progress toward synthesis of a transition metal coordination complex analog of the neocarzinostatin metabolite core

J. R. Olexa,, C. N. Streu.Department of Chemistry and Biochemistry, St. Mary's College of Maryland, St. Mary's City, Maryland 20686, United States

Bioinorganic chemistry is a rapidly growing field with vast pharmaceutical applications. Notable advances have been made in the treatment of a number of complex diseases, including cancer and HIV. The neocarzinostatin metabolite has been well characterized in its binding affinity for a specific hairpin loop structure found on the trans-activating response element (TAR) located on HIV RNA, giving the metabolite potential as an HIV therapeutic. Synthesis of the metabolite through traditional organic chemistry has shown to be difficult, so a transition metal analog has been designed to simplify the synthesis and facilitate structure-activity studies. Progress toward the synthesis of this metabolite core is discussed and the applicability of this methodology to additional RNA sequences and natural products is outlined.

CHED 788

Biological evaluation of a novel series of isoprenylated coumarins as promising pancreatic cancer therapies

Alyssa F. Bacay1,, Maria Jun1,, James Moyer1, Andrew Webb2, Dora Carrico-Moniz1.  (1) Department of Chemistry, Wellesley College, Wellesley, MA 02481, United States  (2) Department of Biological Sciences, Wellesley College, Wellesley, MA 02481, United States

Angelmarin, a coumarin-based natural product isolated from the root of the Japanese medical plant Angelica pubescens, has displayed promising activity against pancreatic adenocarcinoma cell line PANC-1. Given this compound's potential as a pancreatic cancer therapy, structure-activity relationship (SAR) studies have been initiated to discover even more effective compounds and to further investigate the compound's molecular target. A novel geranylgeranylated ether coumarin derivative has been identified as a promising lead structure for further development of novel compounds as pancreatic cancer chemotherapeutics. Cytotoxicity data for a novel lead series against PANC-1 cells under nutrient rich and nutrient deprived conditions will be presented.

CHED 789

Chemical constituents of a methanol extract of Hypericum ellipticum

Keisha Neidrich,, Benjamin Capozzoli, Geneive E Henry.Department of Chemistry, Susquehanna University, Selinsgrove, PA 17870, United States

The Hypericum plant genus has been a consistent source of biologically active natural products. Previous phytochemical studies of hexane and acetone extracts of the leaves of Hypericum ellipticum have afforded a new acylphloroglucinol derivative (elliptophenone A), two new xanthones (elliptoxanthones A and B) and a new benzophenone glucoside (3'-O-beta-D-3'',4'',6''-triacetylglucopyranosyl-2,4,5',6-tetra-hydroxy benzophenone). Some of these compounds exhibited moderate cytotoxicity towards human colon tumor cell lines. In the current study, the methanol extract of Hypericum ellipticum has yielded 3'-O-beta-D-3'',4'',6''-triacetylglucopyranosyl-2,4,5',6-tetra-hydroxy benzophenone, together with other flavonoids and flavonoid glycosides. The compounds were purified using Sephadex LH 20, silica gel and C18 RP column chromatography, together with RP HPLC. Structures were determined on the basis of 2D NMR, IR and MS analyses.

CHED 790

Application of computational docking to examine metabolism of chiral drugs by CYP2C9

Timothy M. Horton1,, Grover P. Miller2, Martin D. Perry, Jr.1.  (1) Department of Chemistry, Ouachita Baptist University, Arkadelphia, AR 71998, United States  (2) Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States

Because chiral drugs make up 50% of drugs on the market, examination of their metabolism could advance understanding of why they are effective. Frequently chiral drugs are cleared much more favorably in one conformation than in the other. Due to their nature and position in the channel where oxidation occurs, certain residues, or amino acids, could act to steer metabolism based on the drug's stereochemistry. Computational approaches including molecular dynamics were performed to simulate metabolism. A novel approach involved the use of the Lennard-Jones potential to estimate the stabilizing energy afforded by each residue to the enzyme-ligand complex. The residues with the largest difference in energy between configurations of drugs were identified for multiple drugs. Several residues, including PHE476, showed much more favorable interaction with one enantiomer of a drug than with the other enantiomer. Such differences based on chirality lent themselves well to the idea of residues steering metabolism.

CHED 791

Computational analysis of ajulemic acid binding sites in PPAYy-similar proteins

Hollyn M. McCarty1,2,, Joseph W. Levy1, Lori L. Hensley2, Martin D. Perry, Jr.1.  (1) Department of Chemistry, Ouachita Baptist University, Arkadelphia, AR 71998, United States  (2) Department of Biology, Ouachita Baptist University, Arkadelphia, AR 71998, United States

Ajulemic acid (AJA), a synthetic analog of THC-11-oic acid, has been shown to induce apoptosis in Ewing's sarcoma (ES) cell lines in vitro; however, the apoptotic mechanism AJA utilizes is currently unknown. X-ray crystallography has revealed AJA bound to only one protein, peroxisome-proliferator-activated receptor gamma (PPARγ), which is not expressed in ES cells. To locate another protein to which AJA binds, a computational approach is taken. Using the functional site analysis program SMAP, the geometric properties of proteins can be compared to proteins on the protein databank. Using PPARγ as a template protein, a list of potential protein targets with similar geometric motifs is created for further investigation. Once a list of proteins is compiled, Surflex Dock, a docking suite within Sybyl-X 1.3 from Tripos Inc., is used to dock AJA with the proteins, using auto and ligand based protomols. Proteins then undergo wet lab investigation utilizing MTT assays.

CHED 792

Antibacterial natural products from Hypericum canadense

Mitchell Lion,, Geneive E Henry.Department of Chemistry, Susquehanna University, Selinsgrove, PA 17870, United States

The Hypericum genus, a member of the Clusiaceae plant family, has yielded a number of natural products which show significant potential as medicinal agents. Acylphloroglucinols comprise the most notable class of biologically active compounds present in the genus. These compounds possess antiviral, antibacterial, antioxidant, anti-inflammatory and anticancer activities. An acetone extract of Hypericum canadense, an understudied species, showed strong inhibition against the growth of a Staphylococcus aureus strain. Purification of the extract afforded two antibacterial phloroglucinol derivatives, uliginosin B and isouliginosin B, terpenes and flavonoid derivatives. The compounds were purified by a combination of silica gel column chromatography and reversed phase HPLC. Structures were elucidated by 2D NMR, MS and IR analyses.

CHED 793

Screening of organic compounds for use as photosensitizers in photodymanic therapy (PDT) treatment of cancer

Cynthia Wilson,, Cierra Baptiste, Kenneth LaiHing.Department of Chemistry, Oakwood University, Huntsville, Alabama 35896, United States

Photodynamic therapy (PDT) is a minimally invasive cancer treatment alternative to current cancer treatments. Studies have shown that photosensitive agents absorb light at selective wavelengths and can chemically change the internal environment of cancer cells by exciting oxygen molecules to the singlet state which reacts quickly with nearby tissues, causing cell death to cancer cells while leaving the surrounding tissue unaffected. We are exploring the light absorbing properties of organic compounds to determine their potential and efficiency as photosensitive agents. Solutions of these compounds, in dimethyl sulfoxide (DMSO) and ethanol, were investigated using UV-Vis spectrometry. Based on their visible absorption spectra, Zinc Phthalocyanine and Manganese Phthalocyanine are the best candidates as photosensitizers currently, with absorption peaks between 600 and 800 nm in both ethanol and DMSO. Other possible candidates will also be presented.

CHED 794

Phenolic profile of select bean/herb varieties using UV-Vis spectroscopy and HPLC

Joseph Tang,, Donald Wharry.Department of Chemistry, St. Edward's University, Austin, Texas 78704, United States

Phenolic acids are organic compounds found in many plant and fruit species. Some have harmful effects, while others have antioxidant properties, making them a popular topic for health food studies. Classifying phenolic quantity is therefore a common method for determining food safety. A Folin-Ciocalteu assay was used to determine total phenolic content in certain dry beans and herbs, with a gallic acid standard. A method for high-pressure liquid chromatography was devised for determining specific phenolic content. After extraction using a solvent containing methanol, water, acetic acid, and butylated hydroxytoluene, samples were analyzed against external standards.

CHED 795

Computational docking analysis of enantiospecificity in CYP2C9 drug metabolism

Shelby C. Cobb1,, Grover P. Miller2, Martin D. Perry, Jr.1.  (1) Department of Chemistry, Ouachita Baptist University, Arkadelphia, AR 71998, United States  (2) Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States

Cytochrome P450s, the largest known super-family of proteins, are most abundant in the liver, where they are known to metabolize drugs and steroids. Of the CYP2 subfamily, CYP2C9 is the most enantiospecific P450 based on metabolic studies; however, the molecular interactions which cause this difference are unknown. To determine how the intermolecular forces differ between enantiomers and the CYP2C9 enzyme, a computational study of molecular dynamics simulations was conducted using Tripos Sybyl-X software to dock a series of chiral drugs into the CYP2C9 crystal structure. The interactions between each ligand and the residues within CYP2C9 were identified, and the energy of each interaction was calculated. These observed interactions and energies allowed for the docking affinity of each residue involved to be determined in order to show which residues contribute to CYP2C9 enantiospecificity. The data obtained will add to future projects studying the broad effects of substrate chirality on metabolic activity.

CHED 796

Spectroelectrochemical characterization of the blood substitute, oxyvita

Nelly Kaneza,, Scott Dorman.Department of Chemistry and Physics, Birmingham Southern College, Birmingham, Alabama 35254, United States

Oxyvita, a zero-linked polymeric bovine hemoglobin is being investigated as a safer hemoglobin-based oxygen carrier (HBOC) due to its homogenous molecular size and structural stability. For oxygen transport and delivery to be effective, the heme-iron has to stay in the reduced form. Once the iron is oxidized, it is no longer able to carry oxygen. To determine the tendency of the Oxyvita Hb to oxidize, its reduction potentials (E°RED) were determined. Using Spectroelectrochemistry (SEC) and Nernst Plot analysis, Oxyvita Hb reduction potentials were investigated and compared to reduction potentials of other hemoglobins. The average reduction potentials for Oxyvita hemoglobin were -112.4±5.6 mV and -166.35±12.6 mV for wavelengths 406 nm and 43 0nm, respectively. These values indicate low resistance to oxidation. However, due to carbon monoxide interference, more trials are needed before any generalizations can be made.

CHED 797

Synthesis of a novel inhibitor of cell wall biosynthesis in Mycobacterium tuberculosis

Michael D Harland1,, Terry J May2, Neil R Thomas2.  (1) Department of Chemistry and Biochemistry, Carroll University, Waukesha, Wisconsin 53186, United States  (2) Department of Chemistry, University of Nottingham, Nottingham, United Kingdom

With the growing threat of Mycobacterium tuberculosis that does not respond to standard antibiotics, new antibiotics are needed to treat this infectious disease. An enzyme known as UDP-galactopyranose mutase (UGM) is an interesting target for inhibiting the growth of Mycobacterium, because of its role in cell wall biosynthesis and its absence in mammalian cells. A virtual screen of the LeadQuest™ library for potential inhibitors identified a compound known as LQ10, which has good inhibition properties with a sub-micromolar IC50. The focus of this research was on developing and synthesizing an analogue of LQ10 that effectively inhibits UGM. The analogue differs by the use of a phenyl group that is thought to increase binding in the active site through additional π-π interactions. Using a 7-step synthetic route starting from a simple piperidine analogue, the final compound was synthesized and purified to be used for inhibition assays of UGM in future studies.

CHED 798

Novel antimalarial compounds

Mark T Schwerkoske,, J. Thomas Ippoliti.Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105, United States

It has been found that certain quaternary ammonium salts play an active role inhibiting the growth of the Plasmodium falciparum parasite, more commonly known as malaria. Through the years the parasite has gained resistance to traditional medications. Variations of quaternary ammonium compounds have shown potent antimalarial properties and have gained attention as a viable new, effective, and relatively cheap malaria treatment. Quaternary ammonium compounds that have a cholesterol moiety attached are not known. A series of 1-bromo carboxylic acids were coupled with cholesterol, and the resulting esters reacted with various diamines and amines to form the novel diquaternary and quaternary ammonium salts. Activities of these compounds were determined by the Swiss Tropical and Public Health Institute via in vitro assay.

CHED 799

Synthesis and computational investigation of 2nd-generation beta-secretase inhibitors

Rebekah Brooks,, Andrew J Lampkins.Department of Chemistry and Biochemistry, Samford University, Birmingham, Alabama 35229, United States

Herein we present the synthesis and computational investigation of a 2nd-generation class of structurally-novel beta-secretase inhibitors. This enzyme, a key player in the neurotoxic amyloid cascade involved in Alzheimer's disease, is an active pharmacological target in both industrial and academic laboratories. Our original design has been modified to optimize biopharmaceutical properties used to predict overall bioavailability and central nervous system penetration (cLogP, tPSA, etc.). We believe the resulting drug candidates will exhibit a more favorable “druggability” profile than their predecessors, while retaining the desired potency. The de novo synthesis of these inhibitors, and their prodrug derivatives, is outlined as is our in silico investigation of their interactions with the target enzyme. Our computational models predict potent (Ki = 109–341 nM), efficient (L.E. = 0.317-0.368) inhibition carried out by a common transition state analog mechanism involving two bifurcated hydrogen bonds (with Asp 32 and Asp 228).

CHED 800

SAR of macrocyclic TMC-95A analogs as inhibitors of the proteasome

Stephanie Steiner,, Frederick Tomlin,, Vincent Peterson, Zack Strater, Marion G. Gotz.Department of Chemistry, Whitman College, Walla Walla, WA 99362, United States

In the search for cancer chemotherapy options, the 20S proteasome has become a target of interest. The natural product TMC-95A is a macrocyclic peptide that has been found to inhibit the proteasome non-covalently through hydrogen bonding. We have designed a new class of modified TMC-95A analogs that include a biaryl ether macrocycle as well as a C-terminal aldehyde that binds to the catalytic nucleophile in the enzyme active site. An SAR study was performed to determine the optimal peptide sequence. It was found that whereas a central leucine residue is most potent in inhibiting the chymotrypsin-like activity, a central asparagine residue is more effective in targeting all three catalytic activities simultaneously.

CHED 801

Progress toward synthesis of a novel trifluoromethyl substituted aurone as a potential anticancer agent

Amelia Zuver,, Brian McKinnon, Chavonda J. Mills.Department of Chemistry, Physics, and Astronomy, Georgia College & State University, Milledgeville, Georgia 31061, United States

In recent years, research has found that the cyclooxygenase-2 (COX-2) enzyme is overexpressed in cancer cells. Research also indicates that COX-2 inhibition decreases inflammation associated with tumor growth. Naturally occurring flavonoid compounds, especially aurones, have been shown to effectively inhibit the COX-2 enzyme and subsequently exhibit anti-cancer activity. Mills, et. al. recently performed molecular docking studies of several novel aurones at the COX-2 active site. As a continuation of this research, a synthetic pathway for one of the promising aurone derivatives, a novel trifluoromethyl-substituted aurone, has been proposed. The structure of the COX-2 binding pocket was taken into consideration during its design. Increased COX-2 inhibitory activity may be attributed to enhanced steric and electron withdrawing effects from the trifluoromethyl group. The target molecule will be synthesized from trifluoromethyl phenol and characterized.

CHED 802

Synthesis of aryl-guanidino polyamine conjugates and inhibition of trypanothione reductase

Jesse Fodero,, Andrew Forrestel, Jessica Stachowski, Mary O'Sullivan.Department of Chemistry and Biochemistry, Canisius College, Buffalo, NY 14208, United States

Protozoan parasites that are members of the family Trypanosomatidae cause human diseases including Chagas' disease in South America (Trypanosoma cruzi) and trypanosomiasis in Africa (T. brucei subspecies). The enzyme trypanothione reductase (TR) is pivotal to the unique antioxidant metabolism of these parasites. This enzyme catalyzes the NADPH reduction of a disulfide of trypanothione. Trypanothione is an unusual glutathione-spermidine conjugate (N1,N8-bis(glutathionyl)spermidine) and the reduced (dithiol) form of trypanothione acts as a reducing agent in several vital processes including maintenance of the parasites' cellular thiol redox balance and reduction of tryparedoxin (which is a substrate for ribonucleotide reductase). Thus inhibitors of TR have potential as novel anti-trypanosomal chemotherapeutics. Here we report the syntheses of several novel aryl-guanidino polyamine derivatives and studies of the inhibiting effects of these compounds on recombinant T. cruzi TR. The polyamines investigated were spermidine (N-(3-aminopropyl)-1,4-diaminobutane) and spermine (N,N'-bis(3-aminopropyl)-1,4-diaminobutane) derivatives with N-carboxamidine and aromatic substituents.

CHED 803

Susceptibility and analysis of triglyceride rich lipoproteins in human blood to chemical oxidative stress

Tyler Poi,, Tim Williams,, Richa Chandra.Department of Chemistry and Biochemistry, Southwestern University, Georgetown, TX 78626, United States

Every year 935,000 Americans suffer from heart attacks; nearly 610,000 result in fatality. Previous studies link the formation of atherosclerotic plaque to oxidized LDL particles, but it is worthwhile to examine other key members of the lipoprotein family. Triglyceride rich lipoproteins (TRL) transport dietary fats to cells and are the metabolic precursors to LDL. Our research delves into the susceptibility of TRL particles to oxidative stress as a possible cause of atherogenesis. Our preliminary research indicates a decrease in protein concentration and structural changes of apo-B100 protein, a major surface protein of TRL in oxidized samples. Our data strongly indicates that TRL undergo a similar free radical oxidation mechanism as LDL. Free radical oxidation of LDL leads to plaque formation and heart disease; it is possible that oxidized TRL particles contribute to the development of atherogenesis as well. Elucidating the mechanism of atherosclerotic plaque development will impact clinical science directly.

CHED 804

Synthesis and evaluation of tautomerically ambiguous nucleosides as potential antiviral agents

Chase Elkin1,, Cody McLeod1,, Vincent Dunlap1, Thomas Kalman2.  (1) Department of Chemistry, Henderson State University, Arkadelphia, AR 71999, United States  (2) Department of Chemistry, University at Buffalo, State University of New York, Buffalo, NY 14260, United States

Antiretroviral therapy for treatment of human immunodeficiency virus (HIV) has developed with great success over the last few decades. While the current therapies are successful, patients often meet with severe side effects and the mutagenic nature of the HIV virus leads to a constant need for new drug development. One such method of development involves incorporation of bases with ambiguous hydrogen bonding faces. We have synthesized a set of nucleosides with such characteristics, which, when incorporated into the viral DNA, will destabilize the DNA. When combined with the high error rate of the RNA polymerase enzymes of the HIV virus, such incorporation may lead to an error catastrophe. Presented here are the results of the synthesis and initial work on the thermal denaturation of DNA duplexes containing the described nucleosides.

CHED 805

Influence of amino acid side-chain mobility, drug binding, and disulfide bonding on the thermal stability of native human serum albumin

Sixbert Muhoza,, Anselme Mucunguzi,, Philip Carlson, Reid Bishop.Department of Chemistry & Physics, Belhaven University, Jackson, MS 39202, United States

Advances in the structure determinations of serum albumin reveal that the binding of different ligands results in a shift in the number and type of salt-bridges resulting from the movements of amino acid side-chains throughout the protein structure. These side-chain movements occur mostly independently of the backbone, which is held in a relatively fixed conformation by 17 disulfide bonds. Here, we present results from a rigorous comparison of the various crystal structures of the protein formed in the presence and absence of various ligands including chloride anion, R- and S-warfarin, and fatty acids. We also present results from biophysical methods including solution differential scanning calorimetry (DSC), fluorescence spectroscopy, and UV-visible spectrophotometry, used to investigate the thermal stability of the protein. Molecular modeling and semi-empirical calculations provide insight into the differential stability of human serum albumin over a range of solution conditions and in the presence of various small molecule ligands.

CHED 806

Assessing the importance of H-bonding at the p-phenyl position in urea-linked heteroarotinoids

Ashlie N Walker,, Shannah M Rider,, Amber E. Williams,, Joshua G. Brock, William J. Kelly.Department of Chemistry and Physics, Southwestern Oklahoma State University, Weatherford, Oklahoma 73096, United States

Urea/thiourea containing heteroarotinoids (1 ) demonstrate great potential as chemotherapeutic compounds. The most effective compound to date contains a p-nitrophenyl group in the structure. As part of an organic chemistry laboratory research experience, we have carried out a qualitative structure/activity project in which the p-nitrophenyl has been replaced by either a methyl or trifluoromethyl group (2 ), in order to assess the importance of H-bonding at this position. The synthesis, characterization and biological activity of these heteroarotinoid analogs will be discussed.

CHED 807

Preparation novel compounds with activity against the malaria parasite, Plasmodium falciparum

Jonathan E Harrell1,, Clare E Gutteridge1, Brett W Sadowski1, Michael T O’Neil2, Patricia Lee2.  (1) Department of Chemistry, US Naval Academy, Annapolis, MD 21402, United States  (2) Division of Experimental Therapeutics, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States

Recent progress in the development of two series of novel antimalarial compounds will be presented. Firstly, the synthesis of three antimalarial compounds expected to possess activity against the malarial cyclin dependent protein kinase, Pfmrk will be described. Secondly, the synthesis of further members of a second novel compound series with promising in vitro efficacy against both blood- and liver-stage P. falciparum will be described. Following the failure of one such compound to cure malaria-infected mice, focus has been to enhance the pharmaceutical properties of this compound series. Newer analogs incorporating structural changes expected to enhance compound polarity have been designed. The in vitro efficacies and pharmaceutical properties of these compounds will be described.

CHED 808

Different route of administration for melanocortin receptor agonist, melanotan II, in the model of cryptogenic infantile spasms

Yosefa Schoor2,, Libor Velisek1, Tamar Chachua1, Jana Veliskova1.  (1) Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY 10595, United States  (2) Department of Biology, Stern College for Women- Yeshiva University, New York, NY 10033, United States

MelanotanII, Melanocortin receptor 3 and 4 agonist, administered intraperitoneally displayed potent effects against spasms in the prenatally primed model of cryptogenic Infantile Spasms (cIS). To confirm the central effects of melanotanII and to understand its true potential as an anti-epileptic drug for Infantile Spasms in humans, a different route of administration was tested in this experiment. The route of intranasal administration which is less stressful then IP and prevents the peripheral effects seen in drugs like ACTH (the first line drug for cIS) was utilized. Due to its small size (ten amino acids) melanotanII was delivered intranasally and tested for its effect against spasms in prenatally betamethasone-primed animals. A concentration of 10mg of melanotanII in 6ml was administered through nostrils (3ml per nostril) in 15 days old rats. Control animals received saline instead of melanotanII. Collected data did not yield significant differences between intranasally melanotanII - and saline-delivered groups.

CHED 809

Effects of rose bengal on the viability of axenic Leishmania cells

Shawn M Sternisha,, David L Cedeño, Marjorie A Jones.Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, United States

We evaluated the effects of rose bengal on the protozoan parasites, Leishmania tarentolae in culture. Rose bengal, with and without encapsulation into silica nano-particles, was incubated with cell cultures, with and without light exposure. Cell viability was assessed using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and by light microscopy. Nano-particles were loaded by stirring a dispersion with a 160 µM solution of rose bengal in water follow by centrifugation multiple times, with the absorbance of the supernatant measured after each centrifugation step. Cells incubated with encapsulated rose bengal or with nano-particles only resulted in the same cell viability (without and without light exposure). They also exhibited no major abnormalities by microscopy. Cells incubated with free rose bengal were inhibited about 86% (following light exposure) relative to control cells and approximately 34% (no light exposure). Cells exposed to the rose bengal assumed a different shape than control cells as observed by microscopy.

CHED 810

Identification of new inhibitors targeted against low molecular weight protein tyrosine phosphatase

Kyle A Richards,, Henry V Jakubowski, Edward J McIntee.Department of Chemistry, College of Saint Benedict/Saint John's University, St. Joseph, MN 56374, United States

Low Molecular Weight Protein Tyrosine Phosphatase (LMW-PTP) plays a vital role in both cell proliferation and intercellular communication. Over-activation of LMW-PTP has been linked to the transformation of cells in the liver, kidney, and breast. Past research has shown the National Cancer Institute's diversity set I and II both contained inhibitors targeted against LMW-PTP. Our research is focused on the identification of novel inhibitors of LMW-PTP based on the National Cancer Institute's diversity set III. Inhibitors were first identified via virtual screening using Maestro (Schrodinger LLC) before being tested through an enzymatic assay. We also attempted synthesizing inhibitors based on the structure of a known inhibitor, pyridoxial 5' phosphate (PLP). Results of these efforts will be presented.

CHED 811

Synthesis, characterization, and evaluation of various 7-benzyloxy, 7-heteroalkyloxy, and 7-heteroaryloxy-4-methyl-2H-chromen-2-ones as potential antioxidants

James K Murray, Brandi S Santaniello,, Kerry N Smallacombe, of Chemistry, Immaculata University, Immaculata, Pennsylvania 19345, United States

A recent report looked at the antioxidant properties of a variety of 4-Schiff base-7-benzyloxycoumarins. Several compounds prepared in this study were found to significantly inhibit the action of several well-known free-radical and ROS species. With the scarcity of reports on other 7-substituted coumarin derivatives, the aim of the current work is to synthesize a variety of diversely substituted 7-Benzyloxy, 7-Heteroalkyloxy, and 7-Heteroaryloxy-4-Methyl-2H-Chromen-2-ones and screen them for antioxidant activity against free-radicals and ROS. The lead compound in this project is 7-benzyloxy-4-methylcoumarin and the initial series looks at the preparation of variously substituted 7-benzyloxy-4-methylcoumarin derivatives. Based on the results of the assays and SAR, substituents will be analyzed and modified for further investigation. The second series of derivatives are prepared by focusing on the incorporation of N-heterocyclic rings at the 7-position, in lieu of the benzyloxy group. Derivatives will be analyzed as previously mentioned.

CHED 812

Synthesis and time dependent toxicity of nicotine analogs

Jenn Pyle1,2,, Robert G. Bergosh1, Kelly Mozena1, Megan Liggett1, Douglas A. Dawson2.  (1) Department of Chemistry, Ashland University, Ashland, OH 44805, United States  (2) Department of Biology/Toxicology, Ashland University, Ashland, OH 44805, United States

Nicotinic receptors control the release of numerous neurotransmitters, including dopamine, acetylcholine, and norepinephrine, and holds promise for treating diseases such as attention deficit hyperactivity disorder (ADHD), Parkinson's and Alzheimer's diseases, and schizophrenia. Our goal is to find analogs that have the potential to bind to the nicotinic receptor, causing the release of these neurotransmitters; and not cause increased heart rate, blood pressure, and nausea that are a result of nicotine usage. The synthesis, purification, characterization, and time dependent toxicity of nicotine analogs will be presented.

CHED 813

Design and synthesis of novel flavonoid derivatives as acetylcholinesterase inhibitors

Gabrielle S DePhillips,, Chavonda J Mills.Department of Chemistry, Physics, and Astronomy, Georgia College, Milledgeville, Georgia 31061, United States

Research has shown that inhibition of Acetylcholinesterase (AChE) improves cognitive function of those afflicted with Alzheimer's disease by increasing neurotransmission in the brain. Structure activity relationship studies indicate AChE inhibitors that are hydrophobic, contain aromatic rings, and mimic the tetrahedral intermediate formed during the decomposition Acetylcholine are highly active. Flavonoid derivatives that contain a 4'-OMe group and lengthy 7-O-sugar have been shown to exhibit AChE inhibition. As a result, the design of novel flavonoid derivatives, which incorporate these crucial structural elements, are presented as promising leads for the treatment of Alzheimer's disease.

CHED 814

Synthesis of a naturally occurring diarylheptanoid and its analogs possessing anti-inflammatory activity

Ryan A McMillan,, Joseph B Wick, Amber J Onorato.Department of Chemistry, College of Saint Benedict | St. John's University, St. Joseph, Minnesota 56374, United States

Recently, the natural product (E)-4-(7-(4-methoxyphenyl)hept-5-en-1-yl)phenol has been isolated and synthesized. This compound, along with other related diarylheptanoids, has demonstrated anti-inflammatory activity. Due to the moderate activity of the lead target, a more potent analog can be envisioned. Therefore, this research project is focused on a Structure Activity Relationship (SAR). The synthesis of the natural product along with several analogs will be presented. Upon completion of these syntheses, anti-inflammatory activity will be evaluated.

CHED 815

D-Aspartic acid in frog nervous system

Elliott Rodriguez,, Travis Comnick,, Nathan Gonzalez, Shahad Khomeis, George Fisher.Department of Physical Sciences, Barry University, Miami Shores, FL 33161, United States

D-aspartic acid (D-Asp) is an endogenous amino acid found in the nervous and endocrine systems of many marine and terrestrial animals (including humans) where it has physiological importance in neurotransmission and hormone regulation. We report finding D-Asp in the nervous system the grass frog Rana pipiens. D-Asp, as analyzed by HPLC, was found primarily in the nervous tissues: spinal cord (~17 nmoles/g, 1% D), brain stem (~16 nmoles/g, 2% D), brain (~8 nmoles/g, 0.8% D), and sciatic nerves (~6 nmoles/g, 2% D). Non-nervous tissues (heart, lung, muscle) contained none or very small concentrations of D-Asp. These results demonstrate that D-Asp is present in the frog nervous system and may have a physiological role as a neurotransmitter.

CHED 816

Synthesis and anti-microbial studies of new heterocyclic-thiosemicarbazone compounds

Elizabeth Melton,, Carrie Thompson, Kathleen Mansur, Edward C Lisic.Department of Chemistry, Tennessee Technological University, Cookeville, TN 38505, United States

Thiosemicarbazone compounds are a class of chemicals reported to have much biological activity, including anti-tumor and antimicrobial properties, mainly due to their metal-chelating abilities. The purpose of this project is to present the syntheses of a new series of alpha-heterolytic thiosemicarbazone compounds and chemical characterizations using 1H NMR along with determining the antimicrobial properties of the new compounds. The minimum inhibitory concentrations (MIC) of each thiosemicarbazone ligand were determined with four bacteria (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa), two yeast (Candida albicans and Sacchromycescervisiae), and a mold (Aspergillus niger). These new compounds exhibit striking anti-proliferative activity, suggesting that the medicinal properties of the compounds can potentially be manipulated into making new broad spectrum medicines, especially when exploiting chelating properties using Cu2+.

CHED 817

Synthesis and antimicrobial studies of acetylpyrazine-thiosemicarbazone (APZ-TSC) ligands and their complexes of Pd2+ and Cu2+

Christine N Beck,, Kathleen Mansur, Carrie Thompson, James Ventrice, Edward C Lisic.Department of Chemistry, Tennessee Technological University, Cookeville, TN 38505, United States

Several new acetylpyrazine thiosemicarbazone ligands have been synthesized in our laboratory and characterized by 1H NMR spectrometry. These new compounds have been shown to ligate transition metals such as Pd2+ and Cu2+ through an N-N-S tridentate system. These biologically active compounds were tested for antimicrobial activity by determining the minimum inhibitory concentrations against four bacteria (Bacillus subtilis, Saphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa), two yeast (Canida albicans and Sacchromyces cervisiae), and one mold (Aspergillus niger). Tests show that the Cu2+ and Pd2+ complexes of these ligands exhibit different activities than the individual ligands.

CHED 818

Interaction of cisplatin and omega-3-fatty acid supplements: An investigation of coordination chemistry

Amberley D Castaneda,, Teresita Munguia.Department of Mathematics and Science, Our Lady of the Lake University, San Antonio, Texas 78207, United States

Cisplatin is by far the most notorious metallic chemotherapy drug on the market, with several studies done on the possible drug resistance. Controversy has arisen in the past years as to whether omega-3-fatty acid supplements neutralize chemotherapeutic effects, specifically that of Cisplatin. This study examined the interaction of cisplatin with omega-3-fatty acid supplements by Fourier Transform Infrared (FT-IR) Spectroscopy, through the titration of omega-3-fatty acid supplement to cisplatin. These studies showed preliminary evidence of a π→d coordination between alkene moiety of the omega-3-fatty acid and the metal center of cisplatin. In summary, further research is needed in regards to the coordination between cisplatin and omega-3-fatty acids pertaining to chemotherapy drug resistance.

CHED 819

Synthesis of four putracine analogs using a series of alcohol solvents

Paige E. Horrigan,, Eden L. Rrichard, Francis C. Mayville, Jr..Natural Science Department, DeSales University, Center Valley, PA 18034, United States

This investigation will involve the synthesis of several putracine analogs produced in a series of alcohol solvents. These nucleophilic substitution reactions with alkyl or acyl halides will produce bis(ethyl), bis(propyl), bis(propionyl) and bis(acetyl) putracine. In this study, using a series of alcohols as the reaction solvents allowed for yields of the polyamine analogs to proceed in a greener manner. There are many advantages for using alcohols over traditional volatile organic solvents in synthesis reactions. Alcohols are preferred solvents as they are more environmentally friendly, can be reclaimed or recycled, and reactions are run at lower temperatures. It was also found, in this work that as the alcohol carbon chain length increases the product yield also increased.

CHED 820

Extraction and analysis of the antioxidant, resveratrol, from various R.W. Knudsen family fruit juices

Nicole M. Misko,, Natalie J. Piger, Francis C. Mayville, Jr..Natural Science Department, DeSales University, Center Valley, PA 18034, United States

The objective of this study was to extract, isolate and analyze the antioxidant, resveratrol from various fruit juices. All juices were manufactured by the R.W. Knudsen Family to ensure sample consistency. The R.W. Knudsen juices were utilized because their products are 100% juice containing no additives or preservatives. The quantification of resveratrol was conducted in order to compare the amount of this antioxidant found in the different fruit juices. In order to extract resveratrol liquid-liquid phase techniques were implemented. The concentration of the antioxidant was quantified using ultraviolet/visible spectroscopy at a wavelength of 306 nm. High Performance Liquid Chromatography was used to isolate and identify the active ingredient from each juice after extraction. The analysis of the data collected from this study will suggest which type of fruit juice contained the most resveratrol.

CHED 821

Synthesis of three spermidine analogs using a series of alcohol solvents

Stephanie E. Hadid,, Francis C. Mayville, Jr..Natural Science Department, DeSales University, Center Valley, PA 18034, United States

This investigation will involve the synthesis of several spermidine analogs produced in a series of alcohol solvents. These nucleophilic substitution reactions with alkyl or aryl halides will produce bis(butyl), bis(pentyl), and bis(benzyl) spermidine. In this study, using a series of alcohols as the reaction solvents allowed for yields of the polyamine analogs to proceed in a greener manner. There are many advantages for using alcohols over traditional volatile organic solvents in synthesis reactions. Alcohols are preferred solvents as they are more environmentally friendly, can be reclaimed or recycled, and reactions are run at lower temperatures. It was also found, in this work that as the alcohol carbon chain length increases the product yield also increased.

CHED 822

Determination of bioactivity in Ilex decidua

Cynthia K. Holland,, Martin J. Campbell.Department of Chemistry, Henderson State University, Arkadelphia, AR 71999, United States

Plants have been used for medicinal purposes for thousands of years, and many people still use primitive medicines today. Most plants, however, remain unexplored. One such example is Ilex decidua (Aquifoliaceae), or the deciduous holly, which grows wild in the Southeast United States. Recently literature reports indicate other hollies in the genus Ilex (Aquifolicacaea), for example, Ilex vomitoria, or the yaupon holly, have shown cytotoxic, anti-inflammatory, or chemopreventative activity. Also, ursolic acid, a known cancer cell growth-inhibitor, was found in the berries of Ilex verticillata. In view of evidence of anti-cancer bioactivity in other Ilex species, the deciduous holly was chosen for investigation. Samples of twigs, leaves, and berries have been collected. We report our initial findings from brine shrimp (Artemia salina (Leech)) toxicity screening and compound isolation and structural studies.

CHED 823

Characterization of glycosaminoglycans and their interactions with TAT peptide to increase drug specificity

Amber Schoenecker,, Lisa E. Prevette.Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105, United States

The interactions between cell-penetrating compounds (CPCs), positively charged molecules that can cross cell membranes, and certain cell surface molecules are not well understood but could be exploited for drug design and development. The goal of this study was to compare binding thermodynamics between the CPC trans-activating transcription factor (TAT) peptide, and four negatively charged, linear polysaccharides known as glycosaminoglycans (GAGs), using isothermal titration calorimetry (ITC). Because GAGs are harvested from biological sources, a colorimetric assay employing 2,3-dimethylmethylene blue was designed to quantify the density of negative charge on each GAG. Two-dimensional nuclear magnetic resonance (NMR) spectroscopy was used to support the results of the colorimetric assays. Together, such careful GAG characterization led to the conclusion that TAT affinity is dependent upon GAG charge density and hydroxyl stereochemistry. Understanding preferential affinity of CPCs to certain GAG structures could aid in cellular delivery of CPC-conjugated drugs by improving drug targeting and specificity.

CHED 824

Isolation and characterization of a suspected phytoalexin from Acer rubrum L

Jared T. Baisden,, Janna Pearson, Beth Miller-Lisy, Robert G. Bergosh, Jeffrey D. Weidenhamer.Department of Chemistry, Geology & Physics, Ashland University, Ashland, Ohio 44805, United States

Wilted red maple leaves are toxic to horses, causing death by oxidation of hemoglobin and inducing anemia. Gallic acid derivatives have been identified as the main oxidants present in the leaves. However, our work has found that a previously unknown phytoalexin is produced by wilting red maple leaves. This compound, which fluoresces blue in certain TLC systems, is present only after wilting. The objective of this study is to identify and characterize this compound so that its toxicity can be determined. Wilted leaves were collected, dried, and extracted with methanol. Leaf extracts have been purified through repeated thin layer chromatography and column chromatography. After successful purification, the structure of the compound will be confirmed by NMR and mass spectral analysis. This research will provide insight regarding the mechanism of fungal defense in Acer rubrum and may also be relevant to the known toxicity of wilted red maple leaves to horses.

CHED 825


CHED 826


CHED 827

Synthesis of anthrax lethal factor inhibitors using a novel potent and selective zinc binding group

Alexander Louis Carlson,, Colton Quick, Matthieu J Rouffet.Department of Chemistry, Point Loma Nazarene University, San Diego, California 92106, United States

Anthrax Lethal Factor (LF) is a zinc metalloenzyme that is mainly responsible for the disruption of the MAPKK pathway leading to the apoptosis of the host cell. Selective Inhibition of LF can be achieved by synthesizing small molecules based on 2-sulfonamidobenzimidazole core which has been recently established as a potent and selective zinc binding group. Several inhibitors were synthesized and tested against LF. The results show several promising leads.

CHED 828

LXR and FXR response in human liver cells

Faith Simunyu1,, Saj Parathath2.  (1) Chemistry and Biochemistry, Denison University, Granville, Ohio 43023, United States  (2) Merck, Rahway, New Jersey, United States

LXR can sense excess cholesterol a