Dr. Ramin Radfar, assistant professor of chemistry,received a Cottrell College Science Award from Research Corporation, a private foundation that aids research in the physical sciences, in November. The Cottrell College Science Program support research to enhance the professional and scholarly development of faculty, along with their students. Radfar’s proposal was funded for over $61,000 and will provide additional support for student research at Wofford.
Dr. Radfar is currently conducting research in the area of structural chemistry, which includes protein purification, crystallization, data collection, and modeling.
"My primary research focus is on the use of x-ray crystallography to determine the three-dimensional structure of biologically important molecules. The research carried out in our laboratory employs a multidisciplinary approach to study macromolecules of biochemical significance and therapeutic importance. Folate binding enzymes, which are an important class of biocatalysts and targets in cancer therapy, is an area of interest. Recently, with the support received from Cottrell College Science Award we were able to study glycolytic enzyme enolase and its interaction with cholesteryl esters. Our laboratory is equipped with the state-of-the-art workstation for computational work and modeling, dynamic light scattering for protein folding/size studies, and high performance liquid chromatography system for macromolecule purification." - Dr. Radfar
For more information on summer research with Dr. Radfar, please consult his web site.
Chemistry students Ben Harlan '03, Trevor Hray '03, Brittnee Jones '04, and Andrew Stachiw '04 have been engaged in various research projects with Drs. Arrington and Radfar, as well as faculty at the University of Connecticut, University of Florida, and the University of Washington. Below are descriptions of their research in the Department of Chemistry at Wofford College.
Andrew Stachiw '04
Andrew Stachiw, a senior majoring in chemistry from Greenville, SC, has been active in research since the completion of his sophomore year. Stachiw has been involved in research with Dr. Ramin Radfar, assistant professor of chemistry at Wofford, and completed a National Science Foundation research project at Washington State University during summer 2003.
At the southeast regional meeting of the American Chemical Society in November 2003, Stachiw made a presentation about his research during the Undergraduate Poster Session. He was award first prize for this presentation on Nov. 16.
During spring 2004, Stachiw will study in Ghana through the Council on International Educational Exchange (CIEE). After graduation, Stachiw plans to work with the United States Peace Corps and pursue graduate studies in chemistry.
Below is the abstract from Stachiw's research during summer 2003.
Prospective Synthetic Nano-Scale Biopolymers
Andrew Stachiw, Wei Wang, Alexander D.Q. Li
Nano-scale biopolymers composed of single strand deoxyribonucleic acid, tetraethylene glycol, and organic chromophores have been synthesized which display several properties: self-assembly, folding, and fluorescence. TEG strands are attached to the chromophore, the terminal ends of this product are modified, and then this monomeric unit is incorporated into a DNA strand through use of a DNA synthesizer. These novel biopolymers display both intra- and intermolecular association (folding and self-assembly, respectively), in which the highly conjugated chromophores stack and experience π-orbital overlap. Folding, which has been evaluated as thermophilic, is the preeminent molecular interaction observed. The resulting π-orbital interactions shift the absorption and fluorescence bands of stacked chromophores and yield varying optical properties. Fluorescence Resonance Energy Transfer (FRET) between different stacked chromophores also produces interesting optical results, especially when the biopolymer’s DNA segments are paired to their complementary DNA.
This research was sponsored by the National Science Foundation and the Department of Chemistry at Washington State University.
Description of Research
Miniscule biopolymers, on the scale of a nanometer, composed of repeating segments of organic compounds (organic chromophores and tetraethylene glycol) and biological macromolecules (deoxyribonucleic acid or DNA), have been produced and reported to display properties of self-assembly, folding, and fluorescence. Self-assembly constitutes an intermolecular organization of these biopolymers. Essentially for illustrative purposes, two or more of these biopolymer strands separated in solution have an affinity for each other and associate themselves together in an organized fashion. Folding refers to intramolecular interaction or organization of these biopolymers. During the folding process, a single biopolymer strand in solution will contort/orient itself into an organized fashion, due to affinities or repulsion that the biopolymer has for itself. Folding is the preeminent molecular interaction observed.
As result, the biopolymer structure organization(s)’ unique optical fluorescence is observed. Because of the resultant energy interactions of these phenomena, the molecules emit different wavelengths of visible light than those emitted when not folded or assembled. Of particular interest are the optical consequences of pairing of a perfect and an imperfect complimentary DNA segment to the DNA incorporated into the biopolymer. Because of the rigid double helix formation of two DNA strands, folding of the biopolymer is completely prevented when a perfect complimentary DNA strand binds to it, resulting with the noted fluorescence not observed. However, when an imperfect complimentary DNA strand binds to the biopolymer's DNA bases, folding is less inhibited and a fluorescence results that somewhat alludes to that of the folded states.
Synthesis or production of these biopolymers is a complex and painstaking process. An organic chromophore (a molecule that has a visible and distinct color) that is commercially available is modified so tetraethylene glycol (TEG) can be bonded to both ends of the organic dye. This product is then altered so that it will bond to DNA on one end, but the other is protected rendering it inert. The "protection" is later removed and the biopolymer exposed to further addition (another TEG-organic dye or nucleotide base), thus the biopolymer is augmented as desired. The latter steps involve use of a DNA Synthesizer and phosphoramidite chemistry.
A practical application of this research involves development of a DNA segment database or matrix to which any unknown DNA segment could be tested and its base sequence determined based upon fluorescence emittance.
|Ben Harlan ’05 and Trevor Hray ‘05
Ben Harlan, a junior majoring in chemistry from Florence, SC, and Trevor Hray, a junior majoring in chemistry from Spartanburg, SC, presented their research concerning the photochemistry of 1-methyl-2-butene-3-yne in a rare gas matrix at the southeastern regional meeting of the American Chemical Society, held in Atlanta, Ga., in November. The presentations were made during the Undergraduate Poster Session on Nov. 16. Dr. Caleb Arrington, assistant professor of chemistry at Wofford, was the research advisor for Harlan and Hray’s project.
Below is the abstract from research completed summer 2003.
Investigating the Photochemical Reactivity of 2-Methyl-1-Buten-3-YNE in a Rare Gas Matrix
Ben Harlan, Trevor Hray, and Caleb Arrington
Low temperature matrix isolation provides the environment for studying the excited state reactivity of small unsaturated hydrocarbons. In this study the photoreactivity of 2-methyl-1-buten-3-yne (2-MB) has been examined. Infrared spectroscopy is used to monitor the loss of reactant molecues and the formation of new compounds upon photolysis with a high pressure Hg-lamp. The tentative assignment for the principle photoproduct of 2-methyl-1-buten-3-yne is the isomerization product 1-penten-3-yne, based on theoretical calculations and deuteration studies. This reactivity varies from the observed reactivity of 1-buten-3-yen studied previously under the same conditions.
|Brittnee Jones ‘04
Brittnee Jones, a senior majoring in chemistry and French, from Waynesville, N.C., has extensive research experience, working with faculty members at Wofford College, the University of Florida and the University of Connecticut.
A Charles E. Daniel scholar, Jones was a member of the Wofford women’s soccer team for two years and studied in Paris, France through the Institute for International Education of Students during spring 2002. In Paris, Jones continued to play soccer and said, “It was exciting to have our practice field at the base of the Eiffel Tower.” She has been selected as a member of the Presidential Seminar for spring 2004. Jones plans to pursue graduate studies in chemistry after graduation from Wofford and aspires to work on cancer research for the National Institutes of Health. Jones is also a member of Kappa Alpha Theta women’s fraternity and Wofford’s chapter of the American Chemical Society.
During summer 2003, Jones worked on cancer research with Dr. Ashis Basu, professor of chemistry at the University of Connecticut.
Information about research at the University of Connecticut
Biological Effects of Radiation/Oxidation: Induced DNA Damages
Brittnee Jones and Ashis Basu
The goal of this project was to study adjacent DNA damages that are believed to be generated by peroxide stress and sunlight radiation. These damages are considered to play a key role in mutagenesis, carcinogenesis, and the aging process. A short strand of DNA, which can be duplicated in both mammalian cells and Escherichia coli, was constructed as a way to determine the effects of DNA damages in mammalian cells. We introduced a single damaged guanosine base adjacent to a uracil base in a preselected area of the DNA. Replication of a normal and damaged fragment of DNA in monkey kidney cells were carried out. The product DNA were isolated and analyzed.
In summer 2002, she completed a research project entitled “Structure of C3H Radical Trapped in Solid Argon.” Jones studied possible interstellar space particles using infrared spectroscopy. These particles were generated by laser ablation of graphite at about -261C in a vacuum. This was done so that gas samples from space can be examined for the presence of the examined gasses. This project was in collaboration with Dr. Martin Vala, professor of chemistry at the University of Florida; Dr. Jan Szczepamski, postdoctoral fellow in the Department of Chemistry at the University of Florida, and Dr. Caleb Arrington, assistant professor of chemistry at Wofford. This research was sponsored by the Department of Chemistry and the Center for Chemical Physics at the University of Florida in Gainesville, Fl. and the Department of Chemistry at Wofford College in Spartanburg, S.C. Research findings for this project were presented in New Orleans, La. last spring at the national meeting of the American Chemical Society and are to be subsequently published.
Information about research at the University of Florida
Structure of C3H Radical Trapped in Solid Argon
Brittnee Jones, Jan Szczepamski, Caleb Arrington and Martin Vala
The C3H radical was generated from an acetylene/argon mixture in a pulsed jet electrical discharge, trapped on a 12K cryostat window, and studied via Fourier transform infrared absorption spectroscopy. Using a 12C2H2 +13C2H2 / Ar mixture, all eight isotopomeric bands for each CC stretch and CH and “linear distorted” (LD). The geometry optimization and harmonic frequency calculations, carried out at various spin unrestricted levels of theory (B3LYP, QCISD and CCSD (T)) for spin doublet structures, indicates that the linear structure is a transition state located ca. 12-90 cm-1 above the linear distorted structure. The root-mean-square (RMS) difference between the observed and calculated frequencies of the eight 12/13C3H isotopomers (at the spin unrestricted HF, B3LYP, QCISD levels with 6-31G(d,p), 6-311G++(d,p), and cc-pVTZ basis sets) for the CC and CH modes are much smaller for the LD structure. It is thus concluded that the C3H radical in Ar matrices prefers the linear distorted structure.
This research was sponsored by the Department of Chemistry and the Center for Chemical Physics at the University of Florida in Gainesville, FL and the Department of Chemistry at Wofford College in Spartanburg, SC.stretching mode of C3H were observed. Two structures of C3H were investigated theoretically, linear (L).
In addition, The National Science Foundation provides a list of Research Experiences for Undergraduates (REU). Research Experiences for Undergraduates (REU) This web site lists major universities (alphabetically by state) which sponsor undergraduates in summer research project. Students participating in these programs can participate in cutting edge research at a major university and gain a better appreciation of what graduate school in chemistry is like. Participation in programs such of these provide a significant enhancement of the graduate school application.