Chemistry

Developing Green High School Laboratory Experiments for Gas Laws and Intermolecular Forces to Fulfill Science Standards

Presenter: Laralin Dixon
Faculty Project Advisor: Sally Henrie

Science standards set high school curriculum requirements to promote the comprehension and organization of core scientific concepts. Green chemistry is an effective way of educating students on these concepts with a minimal effect on the environment as well as a lower risk to the students. After connecting the Tennessee Science Standards and the Next Generation Science Standards with the laboratory experiments already included in The Green Chemistry Laboratory Manual for High School, it was found that experiments for intermolecular forces and gas laws also needed to be included in the manual to satisfy the standards. This research focused on developing these two experiments while using green methods and materials.

Development of a Synthetic Method of the Oxidation of [Cr(TMP)C6O6H2Cr(TMP)]2

Presenter: Hattie Hume
Faculty Project Advisor: Randy Johnston

The oxidation of alcohols is a procedure that has been used in many different fields of chemistry for many uses, including both manufacturing processes and laboratory- scale experiments.1 Chromium (III) benzoquinone complexes can oxidize alcohols to aldehydes or ketones, and these complexes may be able to catalytically carry out the oxidation.2 The complexes may be made by preparing Cr(ClO4)2 and reacting it with a substituted benzoquinone and nitrogen donor ligands. Those ligands could be in this specific case, tetradentate ligands, meaning they will bind four donor atoms to a central atom in order to form a reduced coordination complex. Once the reduced form is produced, a reduction-oxidation reaction can be used to form the oxidized form. Many different methods were attempted to accomplish this, and the results will be reported.

Chromatographic Analysis of Common Analgesic Compounds Using TLC, LC, and HPLC

Presenter: Elizabeth Smith
Faculty Project Advisor: Jimmy Davis

The purpose of this research project was to analyze commonly used over-the-counter analgesic drugs using thin layer chromatography, column chromatography, and high-pressure liquid chromatography. The goal was to create a useful Organic Chemistry lab for students to perform in an effort to learn how to use these techniques. In addition to learning how to use these chromatography techniques, students will be able to identify similarities and differences between the techniques, as well as the molecular reasoning that explains the results of each run.

The Role of Arginine 353 on PRMT1 Activity and Dimerization

Presenter: Brianna Correia
Faculty Project Advisor: Betsy Caceres

Arginine methylation, a post-translational modification, is performed by protein arginine methyltransferases (PRMTs), and is observed in a wide variety of cell types from prokaryotes to eukaryotes. With recent and rapid advancements in epigenetic research, the importance of arginine methylation has been highlighted in various processes throughout the body. Notably, it has a strong correlation to signal transduction, transcriptional activation, repression, as well as many important diseases such as lung, breast, and colon cancer as well as various heart diseases. Through former research conducted, it was found that in PRMT molecules, specifically PRMT1, aspartate 37 (D37) was forming a salt bridge with arginine 353 (R35), and that this is what allowed this molecule to be both activated and regulated. From these findings, the following hypothesis was proposed: is the disruption of the R353-D37 bond causing low activity in the R353K mutant? In order to determine this, studies were performed on wild-type (WT) PRMT1, as well as the R353KD37E variant. These constructs were both expressed and purified for the first time at Union University and had results identical to that of PRMT1 molecules.

Quantification of Pollutants from Concentrated Animal Feeding Operations in the West Tennessee Area

Presenter: Cece Morton
Faculty Project Advisor: Sally Henrie and Conitra C. Morton

Recently, the effects of environmental pollution on air and water quality as well as on human health have been studied regarding the emergence of concentrated animal feeding operations (CAFOs). These operations have historically had significant negative environmental effects, often been due to insufficient building standards and waste disposal. Recently, there have been plans to install a number of these operations in the local area. As such, the primary objective of this research was to develop a procedure for measuring pollutants and to obtain preliminary quantitative data for longitudinal testing. An organized manner for the collection of this data was sufficiently developed, and quantitative measurements of relevant pollutants were obtained near both operational CAFOs and at planned sites. The obtained measurements did not indicate any hazards regarding predetermined standards; however, future measurements will need to be completed to evaluate a change in environmental conditions that can be attributed to these operations.

Greening the Synthesis of a Chiral Sorbent Using a Microwave

Presenter: Evan Holt
Faculty Project Advisor: Sally Henrie

Chiral column chromatography is an efficient method used to provide enantiomerically pure mixtures. This technique is frequently used to provide enantiomerically pure medicines. Previously, a chiral adsorbent was developed that utilized a dendritic precursor attached to silica gel with vancomycin termini as the chiral selector. The product showed promise as a chiral selector however, this method required using a poisoned Raney Nickel catalyst and produced an inadequate branch length for the vancomycin to effectively attach to the termini. In subsequent research, the synthesis of the tri-branched dendritic precursor was developed without the use of a Raney Nickel catalyst and provided longer branches. In this research, a greener, more efficient method for synthesizing the dendritic precursor was developed by incorporating microwave synthesis. This resulted in the chiral adsorbent being synthesized in less time, requiring fewer steps, and using less energy and less hazardous solvents.

Potential Models of a Biochemical Catalyst

Student Scholarship: Paige Bogard
Faculty Advisor: Jimmy Davis

The objective of this research was to find a better method to polymerize phenols that are now polluting many water sources. The compounds that were investigated included DAPTT complexes and porphyrins; propylphenol was used as the phenol to be polymerized. The products of these reactions were compared to the product of the dioxane control experiment with the only compound that seemed to yield significant results being Fe porphyrin. These products were characterized through FT-IR, DSC, 13C NMR, and 1H NMR. The results supported the idea that two different polymers, a phenylene polymer and an oxyphenylene polymer, formed with two possible terminal endings, a quinone and an alcohol ending.

Potential Catalysts for the Polymerization of Phenols

Student Scholarship: Jacob Greene
Faculty Advisor: Jimmy Davis

Diacetylpyridine bis benzoic acid hydrazide (DAPBH) compounds were investigated for their ability to catalyze the polymerization of phenols in the presence of hydrogen peroxide. These compounds were compared to hematin as a control catalyst. None of the DAPBH complexes formed a significant amount of product. The product formed by hematin was investigated using FTIR, hydrogen-NMR, and carbon-NMR to determine the polymer structure.

Automatic Expansion of 3D Motif Palette for RNA Tertiary Structure Design

Student Scholarship: Abby Mausey
Faculty Advisors: Randy Johnston and Joseph Yesselman

RNA is a component of a multitude of biological systems. To perform these cellular functions, RNAs must fold into complex 3D structures. RNA's tertiary structure is unique as it is composed of discrete and module building blocks known as motifs. These motifs can be approximated as static LEGO blocks and have been assembled into a diverse set of RNA nanostructures for many practical applications. The goal of this project is to generate a self-updating library of motifs to be used in RNA design. This library will automatically query the Protein Databank (PDB) to identify new RNA structures. When new structures are identified, they will be processed using DSSR (Dissecting the Spatial Structure of RNA) to separate them into their constituent motifs. By creating a centralized location for all known RNA structural motifs and creating RNA structures from the use of the motif database, this research will achieve its long-term goal.

Development of a Microwave-Assisted Synthesis of N,N'-bis(salicylaldehyde)ethylenediamine and Metal-Salen Complexes Experiment +

Student Scholarship: Breanna Johnson
Faculty Advisor: Sally Henrie

The importance of green chemistry is implemented in developing an experiment for an undergraduate organic laboratory. Domestic and commercial microwaves were employed to green up an experiment that synthesizes salen H2 and Co(salen) by refluxing. The research also includes expanding the experiment to include the synthesis of additional salens and metal salens. The microwave aids in reducing waste, the consumption of energy, reaction time, and expenses. Additionally, the use of other solvents was attempted to "green up" this experiment. The experiment introduces students to structures and fundamental concepts of metal-salen complexes and green principles in the laboratory.

Optimizing a Poly(Lactic acid) Polymer Experiment for an Organic Chemistry Laboratory

Student Scholarship: Naomi Dalton
Faculty Advisor: Sally Henrie

Polymer and green chemistry are two of the fastest emerging subdivisions of chemistry and the focus of very important biochemical and chemical research. The importance of these areas is emphasized in a two-step experiment for the undergraduate organic laboratory where the biodegradable and biosourced polymer, poly-L-lactic acid (PLLA), is synthesized. In this experiment, the first reflux reaction forms an L-lactide intermediate from L-lactic acid. The second reaction forms the final PLLA polymer via a reflux ring opening polymerization (ROP). The project goals of this research were to optimize and adjust this previously developed experimental laboratory procedure for synthesizing and analyzing PLLA in order to increase percent yields. Also, to be developed, was a more time and energy efficient microwave ROP procedure to replace the currently existing reflux ROP procedure. An end group analysis procedure of the final poly-L-lactic acid polymer was also developed to further introduce students to the fundamental concepts of polymer chemistry.

Electrochemical Oxidation of Sodium Glucoheptonate to Its Dicarboxylic Acid Salt (P)

Presenter: Haley Barnette
Faculty Advisor: Michael Hayes

The aldaric acid of sodium glucoheptonate offers the potential to be a superior renewable building block chemical as compared to glucaric acid. Electrochemical oxidation may be an attractive "green" route to this compound. The reaction occurred to an extent such that it has the potential to be an efficient method if the pH and temperature fluctuations are reduced. From C-13 NMR spectra of the reaction product, we concluded that the aldaric acid was present and that side reactions were minimal.

Developing a Nylon 6-6/Poly(lactic acid) Polymer Experiment (P)

Presenter: Colin Coleman
Faculty Advisor: Sally Henrie

The importance of green principles and sustainable polymers is highlighted in a new experiment developed for undergraduate organic laboratories where polylactic acid is formed in a two-step process. L-Lactic acid is naturally and synthetically produced and plays a role in several biochemical processes. The reflux reaction of L-lactic acid and a zeolite catalyst in isobutyl acetate results in a viscous solution of the L-lactide form. Subsequent removal of the catalyst purification, followed by ring opening polymerization reflux in isobutyl acetate and further purification produces the polymer product, polylactic acid. Characterization of the product is done using 1H-NMR and IR spectrum. Degradation is observed and compared to synthesized nylon 6-6 through DSC and TGA. This experiment introduces students to structures and fundamental concepts of polymer chemistry and exemplifies modern advances in sustainable materials.

Use of An Inexpensive Surface Plasmon Resonance Instrument to Determine the Binding of α-Lactalbumin to Fragmented Antibodies (P)

Presenter: Kaitlyn E. James
Faculty Advisor: David Wing

The purpose of this research was to develop a laboratory procedure using an inexpensive surface plasmon resonance instrument for undergraduate use that investigates the binding of antigens and antibodies, specifically α-Lactalbumin and anti-α-Lactalbumin. In order for antigen-antibody interactions to be studied by SPR, antibodies must first be attached to a gold-coated glass slide. 2-Mercaptoethylamine (MEA) was used to break the disulfide bonds of the antibodies so they could be attached to the gold-plated slide by exposed thiols on the Fc tail of the molecule. The fragmented antibodies stuck to the gold surface of the slide and produced a consistent change in the SPR angle. As the antigen solution was slowly pumped through the sample cell and over the antibodies, a further change in SPR angle was expected. However, the observed change was inconsistent. In some trials the SPR angle increased while in others it decreased. Our instrument was not programmed to generate a graph of the response as a function of time - called a sensorgram. Thus, there was no way to determine whether or not the α-Lactalbumin bound to the antibodies, and an analysis of the antigen-binding properties could not be completed. The inexpensive SPR instrument could be used by undergraduates to gain familiarity with the SPR technique, but did not prove to be as useful as hoped for purposes of studying antigen-antibody dynamics.

Analysis and Verification of Alternate Industrial Volatility Testing Methods (P)

Presenter: Benjamin Pinkley
Faculty Advisor: Randy Johnston

The ASTM volatility testing method NOACK has long been subject to investigation and generally known to report highly variable data. Despite this, it is still an industry requirement for many product reporting standards. The industry must move away from this highly variable method and toward one with greater reliability and equal or greater accuracy in the collection and analysis of sample volatilities. This research project endeavored to investigate Thermogravimetric Analysis NOACK (TGA Noack) as a supplemental test method to NOACK and eventually phase out the old method. The emphasis of this experiment lay in the developing of a verification method for the TGA Noack as a viable test. Verification is a central part of how industrial research methods are established and can contribute to the forward progress of industrial knowledge. The analytical end of the verification must be highly thorough, testing products across the extreme ends of product ranges, at multiple locations, and must hold up against the standards of the original method. The TGA Noack method was found, through verification studies, to produce data with a dramatically improved accuracy and allow for modifications that raised said accuracy even more. The TGA Noack method passed the initial rounds of verification and then moved on to interlaboratory round robin examination.

Development of a Greener Method for Modifying Silica Gel with a Dendritic Precursor for Chiral Column Chromatography (P)

Presenter: Alexandra Forderhase Faculty Advisor: Sally Henrie

Chiral column chromatography can be an efficient method to purify a mixture, and is used by the pharmaceutical industry to produce pure medicines. In previous research, a chiral adsorbent was developed that utilized a dendritic precursor attached to silica gel with vancomycin termini as the chiral selector. This method required using a poisoned Raney Nickel catalyst and produced an inadequate branch length for the vancomycin to attach to the termini. A greener method was needed to eliminate the use of the Raney Nickel catalyst and increase the length of the branches. In this research, a tri-branched dendritic precursor with nitrile-termini using acrylonitrile and Trizma® base was synthesized and attached to 3-aminopropyl- functionalized silica gel. Compared to previous research, this greener synthesis uses fewer steps, less hazardous chemicals and increases the branch length by two atoms. Future research will use this method to develop an efficient adsorbent for chiral column chromatography.

Using Thermogravimetric Analysis and X-ray Data to Determine Water Coordination in Seven Coordinate Complexes (P)

Presenter: Seth P. Thibado
Faculty Advisor: Jimmy Davis

In coordination of ligands about a metal center, it is sometimes difficult to detect water coordination due to a variety of causes. X-Ray diffraction, along with the technique of thermogravimetric analysis, was used to determine if one can find the water coordination while solving the crystal of a molecule. In solving the crystal, it was observed that there was one water molecule bonded to the metal center in our zinc complex, and this was confirmed through thermogravimetric analysis, successfully indicating the ability to find water coordination using X-Ray data.

Synthesizing the 7-Carbon Analog of Glucaric Acid (P)

Presenter: Dallas Abraham Faculty Advisor: Michael Hayes

Glucaric acid belongs to the family of sugar diacids known as aldaric acids. It is a 6-carbon dicarboxylic acid that can be produced from the oxidation of glucose with nitric acid. Glucaric acid has gained much attention after being named a top 12 renewable building block chemical by the U.S. Department of Energy. With the rise of interest in "green" chemistry, industries are facing pressure to implement renewable feedstocks. Glucaric acid also has potential uses in detergents, corrosion inhibitors, concrete mixtures, and medicine. The aim of this project was to synthesize the 7-carbon analog of glucaric from sodium glucoheptonate using a process described in an expired patent for the oxidation of glucose. The desired compound was produced along with undesired by-products that prevented the product from being isolated and characterized beyond 13NMR in the time available.

Synthesis of the Catalyst M[DAPTT(H2O)2](ClO4)2 for Bleaching Cotton (P)

Presenter: Rebekah Guthrie
Faculty Advisor: Jimmy Davis

Hydrogen peroxide is often used to bleach cotton at high temperatures, high pH, and a large amount of time. Finding a good catalyst that can maximize the efficiency of bleaching under more reasonable conditions can richly benefit many industries. A ligand called DAPTT was paired with different metals to test its ability to take on the role of catalyzing hydrogen peroxide in bleaching cotton of natural impurities such as Morin which causes discoloration.

Visible Light-Induced, Regioselective, Remote Halogenation of 1,2-Diamino Benzene Derivatives (P)

Presenter: Clint Smith
Faculty Advisor: Blake Watkins

Aryl halides are invaluable tools for synthetic chemistry, having use as building blocks for organic molecules or as intermediates in a wide variety of coupling reactions and industrial processes. Issues with common methods of halogenation of arenes include harsh reagents and reaction conditions as well as the possibility of a mixture of products, so methods to obtain regioselective aryl halides would be highly beneficial. In this research, a method for the preparation of mono-halogenated diamino benzene derivatives was developed in a robust and efficient manner. Use of the greener halogenating reagent trihaloisocyanuric acid was explored. The reaction proceeded smoothly at room temperature, open atmosphere, and gave regioselective products in relatively high yields. The current conditions are tolerated with a broad range of substrates.

Synthesis of Nonsteroidal Analogs of CAmSA AS ANTI- Clostridium difficile Agents

Presenters: Isaac Donkor and Angela Taylor
Faculty Advisor: Mike Salazar

Clostridium difficile is a spore-forming bacterium that commonly infects hospitalized patients. It was discovered that CAmSA (a bile salt analog) inhibits germination of C. difficile spores and prevents the onset of C. difficile -associated disease (CDAD). The steroidal nature of CAmSA makes it undesirable due to potential side effects, so compounds were synthesized as novel nonsteroidal C. difficile antigerminants. The m-formamidobenzenesulfonic acid group of CAmSA was retained in the nonsteroidal analogs for effective interaction with the putative bile acid binding site on C. difficile spores. To synthesize these compounds, basic coupling reactions were used. Most products were isolated by extraction, rotary evaporation, filtration and/or recrystallization. FTIR and NMR were used to confirm product formation. In future experiments, additional nonsteroidal analogs will be synthesized followed by in vitro and in vivo testing for effectiveness of the compounds in preventing CDAD in a mouse model of C. difficile infection.

Potential Green Catalyst for the Bleaching of Cotton

Presenter: Dallas Abraham
Faculty Advisor: Jimmy Davis

Cotton is the most used textile fiber in the world, more than 20 million tons are produced in more than 80 different countries. An important part of the production process is bleaching the cotton, for which Hydrogen Peroxide is most often used. This however is a very time-consuming process that must be done in a harsh environment. The need for a catalyst is apparent, and some compounds have shown to be successful catalysts for the process. This project aimed to synthesize a seven-coordinate complex that would serve as a catalyst without having any negative ecological impact. The synthesized compounds were based on the open-cyclic ligand 2,6-diacetylpyridine bis-benzoic acid hydrazone. The different complexes catalytic potential was tested by adding them to the reaction between H2O–2 and Morin hydrate while being monitored by UV-Vis spectrophotometry, and measuring any changes in the absorbance.

Analysis of Fish Oil Supplements for Omega-3 Content and Heavy Metal Contamination

Presenter: Vernon Stafford, III
Faculty Advisor: Joshua Williams

The dietary supplement industry is one of the largest in the world. Due to an absence of adequate US federal regulations, some supplements have been found to have poor quality and purity. This research aims to evaluate the validity of the content and purity claims made by five fish oil supplement manufacturers. Fish oil is known to contain the important omega-3 fatty acids DHA and EPA, but also dangerous heavy metals. By a quantitative nuclear magnetic resonance analysis, it was determined that none of the tested brands have DHA levels lower than the advertised amount. It was also determined by ICP-OES analysis that there was no detectable concentration of heavy metal contamination.

Synthesis Optimization and Applications of a Chiral Selector Adsorbent

Presenter: Minh Dong
Faculty Advisor: Sally Henrie

Chiral separation technique has become a major field for research since the demand of singly pure enantiomer medicine has increased significantly in the pharmaceutical industry. Previously this research successfully developed a procedure to synthesize a tri- branched macrocyclic antibiotic termini silica gel to eventually use as the adsorbent for chiral stationary phase flash chromatography. This particular research finalized the procedure with optimization when necessary. Moreover, the modified silica gel was also tested to confirm its ability to perform chiral separations on metoprolol and warfarin using flash chromatography. Upon experimental results, the tri-branched vancomycin termini silica gel has shown some potentials in chiral separation, but further development is needed to obtain better resolution of these substances.

Constructing a Low-cost Raman Spectrophotometer

Presenter: Seth Thibado
Faculty Advisor: Joshua Williams

In the modern chemistry lab, spectroscopy is one of the most popular and powerful instrumental techniques that is used for both qualitative and quantitative analysis of molecular compounds. It can be used to determine the structure of a molecule as well as the types of bonds present in it. The issue that arises with spectroscopy, however, is that in purchasing an instrument capable of performing spectroscopic analysis, the cost can become a huge factor and on a budget, can limit whether or not one can even be purchased. Raman spectroscopy is one such technique that has been growing in popularity, but remains less accessible to those on a tight budget. It has been demonstrated that a fully functioning Raman Spectrophotometer could be built by carefully planning for and purchasing the necessary components. Using custom coding and buying used parts whenever possible, a functioning Raman spectrometer was constructed for a total cost of $3,246.57.

Comparing Self-Assembled Monolayers on Gold Sensor Chips for Surface Plasmon Resonance Analysis

Presenter: Alexandra Forderhase
Faculty Advisor: Joshua Williams

Surface plasmon resonance systems are widely used in many bioanalytical experiments due to their ability to obtain data from biochemical interactions in real-time in a non-invasive manner. To analyze the ligand-analyte interaction, modification of the sensor chip surface is often needed, and self-assembled monolayers are useful in immobilizing the ligand to the sensor chip surface. Although thiols are more commonly used for SAM formation, there is reason to believe that disulfides offer better results. To test this, the results of IgG and anti-IgG on a bare gold surface, a carbon disulfide/protein A SAM, and a 6-mercaptohexanol/protein A SAM-modified sensor chip were compared. The results on the SAM-equipped chips resulted in much larger shifts, with the sensor chip modified with the disulfide being the strongest, leading to the conclusion that the modification of the sensor chip surface is beneficial and that disulfides are better for SAM formation on a gold surface.