Chemistry Commons^™

Modeling Etr1 With Isolable Coinage Metal Complexes Supported By Partially Fluorinated, And Methylated Scorpionates, Shawn Glen Ridlen

Chemistry & Biochemistry Dissertations - Archive

Ethylene is a small molecule that functions as a plant hormone that is closely associated with several vital plant functions ranging from germination, shoot and root growth, sex expression, fruit ripening, senescence and abscission. This gaseous hormone is produced by almost every part of the plant, and mediates these processes throughout out the life of the plant. The ethylene response in many plants is initiated by a group of 5 copper based membrane bound receptors, mainly ETR1 (ethylene receptor 1). These receptors are made up of homodimers linked at their N-termini by two disulfide bonds. Each of the monomer units …

Gas Chromatography And Metal Analysis Of Produced Water Treated With A Household Commercial Filter, Chuong Nguyen

Chemistry & Biochemistry Theses - Archive

Unconventional oil and gas extraction activities, including hydraulic fracturing, are a collection of processes used to liberate significant quantities of natural gas and oil in the United States. Many extraction sites are located in large cities, close to residential areas. In some cases, operational malfunctions can result in spills of thousands of gallons of produced waste water and pose a threat of contaminating underground or surface water resources. Produced water contains a complex mixture of salts, volatile and semi-volatile organic compounds, metals, organic acids, and particulates, as well as additives from the drilling process. In this study, we tested the …

Silver Nanoparticles As A Potential Solar Absorber, Benjamin Hardy

Honors Projects

This work reports the development of Silver nanoparticles implanted into a polymer as a solar absorber. The plasmonic nature of silver nanoparticle allows for adjustments to be made in its UV-VIS-NIR absorbance spectrum. A combination of different sized/shaped particles could result in ideal absorption of the majority of the solar spectrum. Allotting this with the stability of a polymer leads to potential solids or solutions that could work as a solar absorber. Tests were also performed to determine whether or not UV-C irradiation during synthesis effects the characteristics of silver nanoparticles, in particular the absorbance. Successful synthesis of silver nanoparticle …

Enzyme Kinetics Studies To Guide Mathematical Modeling Of Microdialysis Sampling To Predict In Situ Biochemistry, Justin M. Klucher

Chemistry & Biochemistry Undergraduate Honors Theses

Microdialysis is a diffusion-based sampling method that can be useful for monitoring various biological systems. Matrix metalloproteinases are a class of enzymes responsible for remodeling the extracellular matrix that, when dysregulated, are linked to various diseases. The delivery method of microdialysis is of particular interest as a sampling technique for enzymatic reactions. Microdialysis was performed in vitro using a model enzyme, porcine pancreatic elastase, because it is a useful substitute for matrix metalloproteinases. A colorimetric substrate for elastase, succinyl-ala-ala-ala-p-nitroanilide, and its product p-nitroaniline were measured using a UV-Vis spectrophotometer. Using an expanded Beer’s Law equation, both analytes’ concentrations were determined …

Chemical Bonding In Novel 0-, 1-, 2-, And 3-Dimensional Chemical Species, Ivan A. Popov

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While the trial and error approach is still being a dominant pathway for synthesis of various compounds in chemistry, computation-driven approaches have recently been shown to be a very efficient way towards the rational design of new materials with tailored properties. In principle, theoretical design of materials may not only significantly reduce the costs associated with the experiment, but may also result in the prediction of novel compounds possessing completely unexpected geometries. These compounds can serve as long-lived catalysts, powerful batteries, efficient solar cells, or reliable energy storage materials. Since geometric structure of any system is related to its electronic …

The Role Of Sulfur Dioxide In Stratospheric Aerosol Formation Evaluated By Using In Situ Measurements In The Tropical Lower Stratosphere, A. W. Rollins, T. D. Thornberry, L. A. Watts, P. Yu, K. H. Rosenlof, M. Mills, E. Baumann, F. R. Giorgetta, T. V. Bui, M. Höpfner, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

Stratospheric aerosols (SAs) are a variable component of the Earth's albedo that may be intentionally enhanced in the future to offset greenhouse gases (geoengineering). The role of tropospheric-sourced sulfur dioxide (SO₂) in maintaining background SAs has been debated for decades without in situ measurements of SO₂ at the tropical tropopause to inform this issue. Here we clarify the role of SO₂ in maintaining SAs by using new in situ SO₂ measurements to evaluate climate models and satellite retrievals. We then use the observed tropical tropopause SO₂ mixing ratios to estimate the global flux of …

The Covalent Interaction Between Dihydrogen And Gold: A Rotational Spectroscopic Study Of H₂-Aucl, Daniel A. Obenchain, Derek S. Frank, Garry S. Grubbs, Herbert M. Pickett, Stewart E. Novick

Chemistry Faculty Research & Creative Works

The pure rotational transitions of H₂-AuCl have been measured using a pulsed-jet cavity Fourier transform microwave spectrometer equipped with a laser ablation source. The structure was found to be T-shaped, with the H-H bond interacting with the gold atom. Both ³⁵Cl and ³⁷Cl isotopologues have been measured for both ortho and para states of H2. Rotational constants, quartic centrifugal distortion constants, and nuclear quadrupole coupling constants for gold and chlorine have been determined. The use of the nuclear spin-nuclear spin interaction terms D_aa, D_bb, and D_cc for H₂ were required …

29si Nmr And Saxs Investigation Of The Hybrid Organic-Inorganic Glasses Obtained By Consolidation Of The Melting Gels, Andrei Jitianu, Sylvian Cadars, Fan Zhang, Gabriela Rodriguez, Quentin Picard, Mario Aparicio, Jadra Mosa, Lisa C. Klein

Publications and Research

This study is focused on structural characterization of hybrid glasses obtained by consolidation of melting gels. The melting gels were prepared in molar ratios of methyltriethoxysilane (MTES) and dimethyldiethoxysilane (DMDES) of 75%MTES-25%DMDES and 65%MTES-35%DMDES. Following consolidation, the hybrid glasses were characterized using Raman, ²⁹Si and ¹³C Nuclear Magnetic Resonance (NMR) spectroscopies, synchrotron Small Angle X-Ray Scattering (SAXS) and scanning electron microscopy (SEM). Raman spectroscopy revealed the presence of Si–C bonds in the hybrid glasses and 8-membered ring structures in the Si–O–Si network. Qualitative NMR spectroscopy identified the main molecular species, while quantitative NMR data showed that the ratio …

A Computational Study Of C-Cn Bond Activation Through Nickel Catalysis Using The Random Phase Approximation, Craig Waitt

Theses, Dissertations and Culminating Projects

This study evaluates the performance of a computational method known as the Random Phase Approximation (RPA) for a Nickel catalyst that activates the C-CN bond of benzonitrile. The reaction mechanism contains two distinct processes. The first process describes the cleavage of the C-CN bond of benzonitrile. The latter describes the fluxionality of benzonitrile about the Nickel atom. Many popular computational methods would struggle to properly describe either or both processes, because they may not perform consistently for transition-metal complexes, are computationally expensive, or have a strong dependence on orbital energy gaps. The RPA provides results with an excellent balance of …

Design, Synthesis And Characterization Of New Analogs Of Tetraiodothyroacetic Acid (Tetrac) As Novel Angiogenesis Modulators And Their Binding Studies With Αvβ3 Integrin, Mary Adeyeye

Chemistry

Angiogenesis is the formation of new blood vessels from preexisting blood vessels. Design and development of novel angiogenesis inhibitors has been validated as a target in several tumor types. Integrins are important ligands that play a critical role in the angiogenesis process, particularly blood formation and local release of vascular growth factors, and they are members of a family of cell surface receptors. Tetraiodothyroacetic acid (tetrac), a deaminated derivative of thyroid hormone T4, is a thyroid antagonist and blocks the actions of T3 and T4 with an interaction site that is located at or near the RGD recognition site identified …

Differentiation Of Hair Using Atr Ft-Ir Spectroscopy: A Statistical Classification Of Dyed And Non-Dyed Hairs, Matthew S. Boll

Chemistry

Although hair is one of the most common and abundant types of evidence found at a crime scene, the current forensic analyses employed underutilize its full potential evidentiary value. Microscopy is the fundamental technique used to analyze forensic hair evidence, but even this routine and well-accepted method has limitations. In this study, non-dyed and dyed hairs from individuals varying in race, biological sex, and age, were analyzed using attenuated total reflection Fourier transform-infrared (ATR FT-IR) spectroscopy. Through the incorporation of multivariate statistical analysis, spectra collected from dyed and non-dyed hairs were differentiated with high accuracy. After hair spectra were determined …

Determining The Role Of Secondary Structure In Translational Control, Dhruv S. Patel

Chemistry

The central dogma of cellular biology asserts that DNA is transcribed to mRNA, which in turn is translated to a protein. This simplistic conduit of gene expression is heavily regulated at multiple levels to ensure proper temporal and spatial expression of genes. One such mode of regulation occurs at the juncture at which RNAs are translated to proteins, known as translational regulation. mRNAs can be translationally regulated by trans-acting factors, such as RNA binding proteins (RBPs), and/or cis-acting factors. Regulation via these two modalities can depend on structure as well as RNA sequence. Secondary structures, such as stem loops, are …

Advances In Separation And Detection In Open Tubular Chromatography, Brian Nicholas Stamos

Chemistry & Biochemistry Dissertations - Archive

Ion chromatography is an important method of analysis in the field of analytical chemistry with applications in a wide variety of applications from pharmaceutical analysis to purity assurance in semiconductor raw materials. The initial motivator for this research, however, was an extraterrestrial one; to perform ionic analysis of Martian soil extracts. The research reported in this dissertation had two major goals. The primary goal was to create a method of conductivity detection that was applicable to small inner diameter open tubular capillaries. An auxiliary goal was to apply this method of detection in ways that were previously not possible. I, …

Synthesis Of Substituted Tetrahydropyrans Using Metal-Catalyzed Coupling Reaction, Amanda Lieu

Renée Crown University Honors Thesis Projects - All

The purpose of this research is to explore the use of cobalt- and iron-catalyzed cross coupling reactions of alkyl iodides containing beta-tetrahydropyran groups to develop a general method to synthesize substituted tetrahydropyrans. Substituted tetrahydropyrans can be used towards the total syntheses of biologically active natural products. The starting iodide compounds underwent sp3-sp3 and sp3-sp2 cobalt- and iron-catalyzed cross-coupling reactions with different Grignard reagents. It was expected that the formation of the coupled product would be faster than the formation of the side products (elimination and homocoupling) and thus yield the desired substituted tetrahydropyrans. The results of this study showed that …

Hydrogen Molybdenum Bronze Catalyzed Hydrolysis Of Cellulose, Claire O. Baker

Undergraduate Honors Theses

In recent years, there has been increasing concern with respect to the large dependence across the globe on nonrenewable energy sources, such as fossil fuels. Ethanol has been explored, however, in alleviating this problem; cellulose, a polymer of glucose molecules, is a precursor to this potentially useful biofuel. However, the strength and rigidity of the cellulose structure has proven to be a difficult obstacle to overcome in this multistep synthesis. Harsh conditions are required, often including concentrated sulfuric acid and extremely high temperatures, to complete hydrolysis to a useful extent. In this work, the hydrolysis of cellulose was performed with …

The Role Of Urinary Pteridines As Disease Biomarkers, Casey Burton, Yinfa Ma

Chemistry Faculty Research & Creative Works

Pteridines and their derivatives function as intermediates in the metabolism of several vitamins and cofactors, and their relevance to disease has inspired new efforts to study their roles as disease biomarkers. Recent analytical advances, such as the emergence of sensitive mass spectrometry techniques, new workflows for measuring pteridine derivatives in their native oxidation states and increased multiplexing capacities for the simultaneous determination of many pteridine derivatives, have enabled researchers to explore the roles of urinary pteridines as disease biomarkers at much lower levels with greater accuracy than with previous technologies or methods. As a result, urinary pteridines are being increasingly …

Channel Bar Morphology, Distribution, And Mining-Related Geochemistry In The Big River, St. Francois County, Missouri: Implications For Geomorphic Recovery, Lindsay Marie Olson

Graduate Theses/Dissertations

Tailings releases associated with large-scale historical Pb mining in St. Francois County, Missouri resulted in system-wide contamination of Pb and excess sediment in the Big River. Previous studies have addressed basin and segment scale variability of the contaminants; however, little is known about reach and bar scale variability. This study addresses how mining sediment inputs influence bar form and geochemistry across a range of scales. Bar sediment samples were collected at 21 reaches and analyzed for particle size and geochemistry, while air photo analysis was used to evaluate channel morphology, bar type, and area. Bar area is initially low in …

Molecular Basis Of Substrate Recognition In Bjai, An Ahl Synthase From Bradyrhizobium Japonicum, Nicole Cornell

Boise State University Theses and Dissertations

Resistance to antibiotics has become a major challenge in today’s society for treating bacterial infections. Inhibition of quorum sensing has a potential to be a non-antibiotic based therapeutic that could be used to fight these bacterial infections. Quorum sensing is a cell density dependent, intercellular communication mechanism that bacteria use to synchronize behavior such as virulence and resistance to antibiotics. If this switch from planktonic to communal behavior can be inhibited, the bacteria will be less virulent. One possible way to accomplish this is by inhibiting the enzymes that are responsible for making the quorum sensing signaling molecules in Gram-negative …

Exploring Thermoresponsive Affinity Agents To Enhance Microdialysis Sampling Efficiency Of Proteins, Thaddeus Vasicek

Graduate Theses and Dissertations

Affinity agents increase microdialysis protein relative recovery, yet they have not seen widespread use within the microdialysis community due to their additional instrumentation requirements and prohibitive cost. This dissertation describes new affinity agents for microdialysis that require no additional instrumentation to use, have nearly 100% particle recovery, are 7 times more cost efficient than alternatives, and have low specificity enabling their use for a wide variety of proteins. Initially gold nanoparticles were chosen as an affinity ligand support due to their high surface area/volume ratio and colloidal stability. Poly (N-isopropylacrylamide) was immobilized to the gold nanoparticles, which served to sterically …

A Targeted Drug Delivery Strategy For Trypanosomiasis Towards A Diastereoselective Boronate Ester Mediated Intramolecular Diels-Alder Cycloaddition, Heeren Manoj Gordhan

All Dissertations

Human African trypanosomiasis (HAT), commonly called African sleeping sickness, is caused by bloodstream form Trypanosoma brucei and has the potential to affect millions of people in sub-Saharan Africa. Treatments have existed for the past fifty years, but are characterized by severe adverse side-effects and poor efficacy. Trypanosomes generate ATP through glycolysis, or the metabolism of glucose, which is catalyzed by enzymes called hexokinases (TbHK1 and TbHK2) in trypanosomes. Through high-throughput screenings (HTS) and structure-activity relationships (SAR), both hexokinases could be targeted with small molecules to inhibit the first step in the glycolytic pathway of trypanosomes. Of the two hexokinases, TbHK1 …

Design And Characterization Of Plasmonic Nanoprobes And Interparticle Interactions For Surface Enhanced Raman Scattering And Biomolecular Detection, Zakiya Skeete

Graduate Dissertations and Theses

Functional nanoparticles serve as an intriguing class of probes in medical theranostics for enabling rapid, sensitive, multiplexing, and point-of-care treatment and diagnosis. One important aspect of these applications is the exploitation of the unique plasmonic properties of certain metal nanoparticles. A key challenge is the understanding of effective harnessing of the plasmonic coupling of the nanoparticles upon interacting with the targeted biomolecular species. This thesis work focuses on investigating the interparticle interactions of chemcially-labled and bioconjugated gold and silver based nanoparticles and their influences on the plasmonic coupling for specctroscopic detection of biomolecules. Examples of the interparticle interactions include dye-mediated …

Synthesis Of Polythioether Nanoparticles Via Thiol-Alkene/Alkyne Photopolymerization In Miniemulsion, Susan E. Walley

Honors Theses

Emulsion-based processes – such as miniemulsion polymerizations – provide well-studied synthetic routes to polymer nanomaterials. Miniemulsion polymerizations are characterized as aqueous dispersions of small, narrowly distributed monomer droplets created through high shear and stabilized against Ostwald ripening/collisional degradation by addition of an appropriate surfactant and costabilizer. In this work, thiol–alkene/alkyne photopolymerization in miniemulsion is demonstrated as a simple, rapid, and one-pot synthetic approach to polythioether nanoparticles with tuneable particle size and clickable functionality. Nanoparticles with mean particle diameters ranging from 45 nm to 200 nm were synthesized through simple modifications to the miniemulsion formulation and processing parameters. Facile access to …

Kinetic Study Of Conjugated Polymer Packing And Agglomeration, Skye R. Travis

Honors Theses

Although organic electronic materials are flexible, cheap to fabricate, and molecularly tunable, their performance has generally been less efficient than that of their inorganic counterparts. Chemical doping has been attempted as a method to increase the efficiency of organic materials. During this process, an organic material, typically a conjugated polymer, is exposed to an oxidant/reductant, called a dopant. Electron transfer between host polymer and dopant molecules increases the charge carrier density in the doped host material, making it a more efficient conductor. The effects of doping using 2,3,5,6-tetrafluoro-tetracyanoquinodimethane (F4TCNQ) on low molecular weight poly(3-hexylthiophene-2,5-diyl) (LMW P3HT) in varying ratios of …

Synthesis Of A Thermally Reversible Cross-Linked System Using Electrophilic Cleavage/Functionalization Of Poly(Isobutylene-Co-Isoprene), Savannah H. Steadman

Honors Theses

Multifunctional polyisobutylenes (PIBs) are of great academic and commercial interest. Current methods to create these materials currently utilize prohibitively expensive synthetic strategies. Recently, Storey et al. reported a novel method for the synthesis of multifunctional PIB which is more commercially viable than the current methods. For this research, the material produced via this technique was utilized to create a thermally reversible crosslinked system using Diels-Alder chemistry. To achieve this, a bromide-functional polyisobutylene obtained via electrophilic cleavage and functionalization of butyl rubber was split into two portions and further functionalized. The first portion of the bromide-functional PIB was reacted with furfuryl …

Characterization Of Epoxy/Amine Networks With Glycidal Polyhedral Oligomeric Silsesquioxane Surface Modified Silica Nanoparticles, Reese K. Sloan

Honors Theses

Silica nanoparticles were surface modified with octa-functional glycidal polyhedral oligomeric silsesquioxane (G-POSS) and incorporated into an epoxy/amine system in an effort to increase the mechanical performance of the inorganic/organic hybrid material. The silica nanoparticles were first functionalized with 3-aminoprpyltrimethoxysilane (APTMOS) at 5 and 10 weight percent, and then modified with G-POSS at ratios of 1:10 and 1:5 (APTMOS: G-POSS). The modified particles were then incorporated into an epoxy/amine network consisting of diglycidyl ether of bisphenol A (DGEBA) and aromatic amine, diamine diphenyl sulfone (4,4’ DDS) at 1 and 5 weight percent, resulting in 8 different formulations. The incorporation of the …

Studies Towards The Synthesis Of (-)-Centrolobine Via The Carbonyl Ene Reaction Of Exocyclic Enol Ethers, Brianna Shores

Renée Crown University Honors Thesis Projects - All

The goal of this study is the synthesis of centrolobine 7, a naturally-occuring compound that exhibits anti-parasitic and anti-inflammatory activity.

The strategy is to utilize the carbonyl ene reaction to form the 2,6-disubstituted framework of centrolobine 7 from exocyclic enol ether 110 and aldehyde 111. Exocyclic enol ether 110 would be synthesized via literature procedures starting from commercially available glutaric anhydride 11 and anisole 114.

The work completed to date optimizing the following reactions: Friedel-Crafts acylation of glutaric anhydride 11 and anisole 114, the reduction of alcohol 116, and cyclization of alcohol 116 to lactone …

Phospholipase Dζ Enhances Diacylglycerol Flux Into Triacylglycerol, Wenyu Yang, Geliang Wang, Jia Li, Philip D. Bates, Xuemin Wang, Doug K. Allen

Faculty Publications

Plant seeds are the primary source of triacylglycerols (TAG) for food, feed, fuel, and industrial applications. As TAG is produced from diacylglycerol (DAG), successful engineering strategies to enhance TAG levels have focused on the conversion of DAG to TAG. However, the production of TAG can be limited by flux through the enzymatic reactions that supply DAG. In this study, two Arabidopsis phospholipase D_ζ genes (AtPLD_ζ1 and AtPLD_ζ2) were coexpressed in Camelina sativa to test whether the conversion of phosphatidylcholine to DAG impacts TAG levels in seeds. The resulting transgenic plants produced 2% to 3% more TAG …

Fluorescence And Uv-Vis Studies Of Quinone-Induced Protein Modifications, Charles A. Thomas Jr

Honors Theses

Quinones are the metabolites of a class of chemicals known as polycyclic aromatic hydrocarbons. These chemicals have been found to be toxic in the environment, especially when interacting with certain proteins. In this study, we investigated the modification of Lysozyme and Ribonuclease A by a series of benzoquinones as well as few naphthoquinones. Fluorescence spectroscopy was used to measure the degree of modification of Lysozyme and Ribonuclease A when incubated with quinones at differing concentrations and for various times. All reactions, unless noted, were carried out in a phosphate buffer (pH=7.0) at 37°C to mimic physiological conditions. The fluorescence intensity …

A Study Of The Photoacoustic Effect In Ethylene Gas, Jay Nguyen

Honors Theses

Ethylene, C2H4, is a plant hormone produced and released naturally by plants and soil microorganisms. This colorless, flammable gas has a slightly sweet odor usually only recognized by those who have handled ethylene before. In situ analyses of this gas and many other potentially harmful gases outside of the laboratory are often difficult to perform due to the lack of a portable yet reliable unit capable of precisely and accurately detecting and measuring the concentrations of these gases at trace gas concentrations of a few parts per billion. In this research project, photoacoustic spectroscopy was used to detect and measure …

Simplified Reversed Chloroquines To Overcome Malaria Resistance To Quinoline-Based Drugs, Bornface Gunsaru, Steven J. Burgess, Westin Morrill, Jane X. Kelly, Shawheen Shomloo, Martin J. Smilkstein, Katherine May Liebman, David H. Peyton

Chemistry Faculty Publications and Presentations

Building on our earlier work of attaching a chemosensitizer (reversal agent) to a known drug pharmacophore, we have now expanded the structure-activity relationship study to include simplified versions of the chemosensitizer. The change from two aromatic rings in this head group to a single ring does not appear to detrimentally affect the antimalarial activity of the compounds. Data from in vitro heme binding and beta-hematin inhibition assays suggest that the single aromatic RCQ compounds retain activities against Plasmodium falciparum similar to those of CQ, although other mechanisms of action may be relevant to their activities.