2024 Design and Research Conference

Determining Km, Vmax, and Ki for a Bacterial Spore-Associated Enzymatic Activity of Inosine-E-Purine Nucleoside Hydrolase

Team Member: Carlie McNeal

Advisor: Dr. Rebecca Giorno

Bacillus anthracis is a spore-forming bacterium that causes anthrax. The spore of B. anthracis is formed during sporulation, and a dormant cell is left. Within the spore are enzymes that break down chemicals known as germinants that cause germination. Inosine-uridine-preferring nucleoside hydrolase (IunH) is one of these enzymes, and its purpose is to break down inosine, a germinant, into its two non-germinant components, D-ribose and hypoxanthine. While B. anthracis spores are difficult to decontaminate, germinating spores are much easier. Therefore, inhibiting IunH could propose a germination-inducing step in decontamination efforts. In this study, the enzyme kinetic parameters Km and Vmax will be determined first to understand how readily the breakdown of inosine happens. These parameters will be determined using the Lineweaver-Burk approach to enzyme kinetic analysis after an assay is performed on the spore population following absorbance at 280 nm observed over time. After these parameters are determined, two inhibitors will be tested on the spores, and the Ki values of each will be determined along with the type of observed inhibition. With the information gathered from this study, the inhibition of IunH to promote germination will be better understood and could lead to the development of a germination-inducing step for decontamination.

Usage of Lab-Built Solution-Cathode Glow-Discharge Atomic Emission Spectrometer to Determine Concentration of Lithium In Brines

Team Member: Gray Andres

Advisor: Dr. Sven Eklund

Lithium is in rising demand, and there is a need for an inexpensive method to quantify its concentration within brine water. Solution-Cathode Glow-Discharge (SCGD) is a low-power, low-cost, and portable excitation source for atomic optical emission spectroscopy (AES). SCGD is used in the quantification of elements within liquid solutions by generating an atomic emission plasma between the flowing liquid cathode and a tungsten anode. SCGD has been used in prior research to determine elemental concentrations in water samples; however, in this project, we are constructing a SCGD to determine specifically lithium concentrations in brine samples at the parts per billion level.

Corrosion Resistance of Poly(Oxy Phenylene)(Pop) Barrier Coatings on Stainless Steel Using Electromechanical Impedance Spectroscopy

Team Member: Savannah Spivey

Advisors: Dr. Erica Murray

The corrosion resistance of poly (oxy phenylene) (POP) barrier coatings on austinite steel was studied to assess the potential for preventing galvanic corrosion between metal components commonly used in automobiles and other vehicles. An electropolymerization technique was used to apply the POP coating onto 316 stainless steel plates with 3” x 3” dimensions. The polymerization mixture composed of 0.40M allylamine, 0.23M 2-allylphenol, and 0.23M 2-butoxyethanol in a 1:1 DI water-methanol solution was applied using a voltage of 10 V for one hour. Electrochemical impedance spectroscopy (EIS) was performed to assess the corrosion resistance of the coating. EIS is an effective method for evaluating corrosion resistance as the data can reveal corrosion reactions occurring at different time constants (i.e., diffusion, charge transfer, and other fundamental processes). EIS is highly sensitive to changes at the coating surface, within the coating, and at the coating/metal interface. The EIS measurements of the POP coatings on 316 stainless steel samples were collected using a 3-electrode corrosion cell in a 5% NaCl electrolyte solution. The data was collected every 3 days over 21 days. Measurements were made in triplicate to ensure the data was stable and reproducible. Confocal Imaging was used to observe the coatings post-corrosion testing to evaluate the coating integrity and aid in the interpretation of EIS results. Noticeable changes in the coating resistance were observed following corrosion testing, which suggested that increasing the coating thickness and/or modifying the polymerization mixture may promote corrosion resistance.

BREAK

Fly Ash as a Precursor for Pine Needle Templated Alumionosilicate Xeroxgels

Team Member: Ian Misiak

Advisor: Dr. Sven Eklund

Fly ash, a mostly silica and alumina waste product from burning coal, created a low-density, high thermal capacity, and low thermal conductivity SiO2 – Al2O3 compound by infiltrating de-lignified pine needles. Pine needles were chosen as a template for their highly porous nature which gives it insulating properties. Also, their aspect ratio makes them suitable as an additive for various materials. To increase the compressive strength of the aluminosilicate aerogel, the calcined pine needles were put into an aminopropyltrimethoxysilane solution and stirred to induce crosslinking on the surface. The product was characterized using SEM, XRD, and FTIR to ensure the removal of organic material was successful, to ascertain replication of the wood fiber structure of the pine needles, and to reveal the formation of any crystallinity. The product’s effectiveness as an additive to increase the insulating properties of materials was measured by determining the change in thermal conductivity when mixed with standard paint samples.

Bottle Stir vs Soxhlet Extraction of Parthenolide from Magnolia Grandiflora, Followed by Flash Chromatography Separation

Team Member: Erin Timm

Advisor: Dr. Sven Eklund

Parthenolide is a sesquiterpene lactone whose unique chemical properties allow it to be used effectively for a wide variety of treatments. Traditionally, the leaves of feverfew have been used in folk medicine as a treatment for many mild ailments such as headaches, colds, and arthritis due to their parthenolide content. Recent studies have shown promising future drug development using parthenolide in the treatment of more serious conditions like cancers and rheumatoid arthritis. Magnolia leaves are also rich in parthenolide and are native to the state of Louisiana. Their chemical resemblance to feverfew and abundance in the area make Magnolia a good research candidate in the quantification of parthenolide extracted from plant leaves. Medicines containing parthenolide can be used to subside pains resulting from various conditions, reduce tumor activity, and prevent or treat inflammation. Parthenolide is one of many sesquiterpene lactones that can be extracted from natural plants and separated using silica column chromatography for analysis. In this experiment, Magnolia leaves are collected, ground, and subjected to two extraction techniques using dichloromethane: bottle stir and Soxhlet extraction. The parthenolide from each extraction technique is separated by reversed-phase flash chromatography and HPLC using a C-18 silica column with a 55:45 v/v% acetonitrile: water mobile phase and then characterized and quantified by FTIR, UV-vis, and NMR spectroscopy. Previous studies found the highest yield of extracted parthenolide via bottle stirring extraction. The conclusions reached in this study are intended to contribute to further research into the most effective technique in extracting the highest concentration of parthenolide from Magnolia leaves for use in future drug development.

Degrading Organic Pollutants via Generation of Radical Oxygen Species from Piezoelectric Materials

Team Member: Nathan Holley

Advisors: Dr. Sven Eklund

The presence of organic pollutants in water is a growing concern due to their impact on aquatic ecosystems and public water sources. Pesticides, pharmaceuticals, and other organic compounds are commonly found in water supplies across the United States. The issues posed by these contaminants in the water are serious and can cause lasting health effects. Current methods of removing organic pollutants from water require an outside energy source, which can be circumvented by applying piezoelectric materials. A piezoelectric material generates an electric charge from applied mechanical pressure, such as the motion of water down a drain. This generation of an electric charge causes radical oxygen species to form in the presence of organic pollutants, which, in turn, degrades the organic pollutants. MoS₂ is the principal piezoelectric compound being researched. MoS₂’s ability to degrade organic contaminants such as dyes, antibiotics, and other organic materials is being investigated.

Additionally, the factors influencing its effectiveness as a piezo catalyst are of specific interest. MoS₂ was synthesized via reacting thiourea and MoO₃ in a hydrothermal reaction vessel at high temperatures. To test the ability of MoS₂ to degrade organic materials, the compound was added to a cuvette containing the organic material, and the cuvette was suspended in an ultrasonicator to provide the required mechanical stress. The concentration of the organic material over time is found by plotting the fluorescence intensity of the mixture over time. From this data, the catalyst’s ability to degrade organic compounds can be determined.

Understanding the Formulation, Reactivity, and Physical Properties of Anionic Lanthanide Complexes

Team Member: Benjamin Willis

Advisor: Dr. Elisabeth Fatila

In the last few decades, light-emitting diode technology has been increasingly implemented and studied for use in optical displays and devices. While several families of compounds can give rise to these LED behaviors, lanthanide coordination complexes are well-known for their optical and magnetic properties. Lanthanide beta-diketones are simple coordination complexes that can be difficult to purify and identify. The ability of lanthanides to have high coordination numbers allows them to coordinate to three, four, or possibly even five beta-diketone ligands. Previous work focused on the electron-withdrawing Hhfac (1,1,1,5,5,5-hexafluoro-2,4-pentadione) ligand, and we seek to extend this work to other beta-diketonate complexes. We have been investigating the synthesis of complexes containing beta-diketones with phenyl groups that are less volatile but should be amenable to recrystallization. These phenyl-containing beta-diketonate ligands are possible antenna ligands for luminescence. We show the synthesis and recrystallization of these complexes and characterize these compounds by nuclear magnetic resonance ( 1H, 13C, and 19F) spectroscopy, Fourier-Transform infrared spectroscopy, fluorescence spectroscopy, and powder X-ray diffraction to further understand these anionic complexes’ behaviors and structures.

Faculty Meeting with Advisory Board