Chemistry Commons^™

Silicon And Tin Substituted Halocyclopropanes: Approaches To New Carbenes And Strained Cyclic Allenes, Noura Srour

Honors Theses

Chloro(trimethylsilyl)carbene and chloro(trimethylstannyl)carbene were generated through photolysis of cyclopropanated phenanthrene precursors which were synthesized in two steps. The photolysis reactions were done in the presence of cis and/or trans-beta-methylstyrene. Though product peaks corresponding to the carbene-alkene adducts were observed in the GCMS, the yields were too low for their isolation and complete characterization. Density functional theory (DFT) calculations were performed on the stereoisomers of the precursor to Chloro(trimethylsilyl)carbene and the carbene itself. Surprisingly, Chloro(trimethylsilyl)carbene’s triplet state was found to be more stable than the singlet at this level of theory.

In a related project, (1-bromo-1a,9b-dihydro-1H-cyclopropa[l]phenanthren-1-yl)trimethylstannane, was …

Raman Spectroscopic And Computational Study Of Hydrogen Bond Interactions Between Guanidine Hydrochloride, Trimethylamine N-Oxide (Tmao), Urea, And Water, Andrew Kamischke

Honors Theses

Proteins are broken down in the body and produce water, CO2, and ammonia as by-products. Ammonia is toxic to cells, making it a priority to be excreted. Urea is the key route for the transportation of ammonia out of the body and is the main component of urine. Guanidine is another important nitrogen-containing molecule that is structural like urea and plays important biological roles in the stabilization of proteins. Guanidine hydrochloride and Urea are known to denature proteins and this functionality continues to be a topic of great interest. Urea and guanidine contain many hydrogen bonding sites and interactions with …

Assembly Of A Protein-Based Hydrogel As A Vehicle For In Situ Drug Delivery, Austin Carroll

Honors Theses

The goal of this work is to develop a self-assembling, protein-based gel to deliver drugs at the site of chronic inflammation. There are two engineered protomers that comprise the gel; calmodulin- and M13- are their critical components. Numerous enzymes have been shown to undergo calcium-dependent regulation by calmodulin, an intracellular protein highly resilient to its chemical environment. One of these enzymes, myosin light chain kinase, contains a remarkable 26 residue portion known as the M13 peptide that has been demonstrated to bind to calmodulin in the presence of calcium through hydrophobic interactions. Because the extracellular space in vivo constitutes an …

Studies Of Carbonaceous Materials Using Raman Spectroscopy, Cameron L. Smith

Honors Theses

Various carbonaceous materials including graphene, treated biochar, and C60 were studied using Raman spectroscopy with particular attention given to the treatment process and the Raman enhancement methods. Such studies that focus on the treatment process are useful in determining the extent to which the species was affected via shifts in the Raman peaks. Previous collaborations have proven successful when multiple samples were studied and analyzed. The attempt to create a novel Raman enhancement technique via combination of two previously recorded techniques was ultimately unsuccessful but further work is necessary.

Energetics And Vibrational Signatures Of Nucleobase Argyrophilic Interactions, Suhwan Paul Lee

Honors Theses

This study investigates the interactions of both purine (adenine and guanine) and pyrimidine (cytosine, thymine, and uracil) nucleobases with a pair of silver atoms (Ag2). Full geometry optimizations were performed on several structures of each nucleobase/Ag2 complex and the corresponding isolated monomers using the M06-2X density functional theory (DFT) method with a correlation consistent triple-ζ basis set augmented with diffuse functions on all atoms and a relativistic pseudopotential on Ag (aug-cc-pVTZ for H, C, N, and O and aug-cc-pVTZ-PP for Ag; denoted aVTZ). Harmonic vibrational frequency computations indicate that each optimized structure corresponds to a minimum on the M06-2X/aVTZ potential …

O-Glcnac Post Translational Modification Of Hypoxia-Inducible Factor (Hif) Proteins, Hailey Elisabeth Grisham

Honors Theses

O-linked β-N-acetylglucosamine (O-GlcNAc) post-translational modification (O- GlcNAcylation), plays a vital role in many metabolic pathways, including those of numerous diseases. New research methods and basic functional roles of O-GlcNAc post- translational modification on metabolism, human health, and cancer are quickly developing, but a vast amount of research remains on the specificity of this pathway towards specific proteins. In this study, T47D breast cancer cells were used as an in vitro model to investigate the effects of O-GlcNAc modification on hypoxia-inducible factor (HIF) proteins.

Investigation Of Vibrational Signatures Of Nitrobenzenes Enhanced By Argyrophilic Interactions, Hailey Reed

Honors Theses

This investigation studies the interactions between various nitroaromatic high energy density materials (HEDMs) and a pair of silver atoms (Ag2). Additionally, we examine the changes in frequency, infrared (IR) intensities, and Raman activities induced by the Ag2 unit as the complexes form. Full geometry optimizations of the isolated HEDM molecules as well as complexes where Ag2 is bound to various argyrophillic sites of these compounds have been carried out along with the corresponding harmonic vibrational frequency computations using the M06-2X density functional with a correlation consistent triple-ζ basis set augmented with diffuse functions on all atoms and a relativistic pseudopotential …

Cell-Free Telomere Dna As A Biomarker For Treatment Response And Tumor Burden In Glioblastoma, John P. North

Honors Theses

Telomeres are repeated nucleotide sequences that cap the ends of each chromosome in eukaryotes. Telomeres are among the earliest genomic sequences to be degraded during apoptosis, potentially providing a biomarker of cell death. To study this, we quantified telomeres in serum from Glioblastoma and non-cancer patients. Cell-free DNA was isolated by centrifugation to remove intact cells, and purified using a QIAamp DNA Blood Midi Kit (Qiagen). Cell-free telomeric (cf-tel) and cell-free actin (cf-actin) DNA were analyzed with quantitative PCR. Total cell-free DNA was measured with PicoGreen assays. We hypothesize that patients with Glioblastoma tumors have higher cf-tel DNA levels than …

Purification Protocol Development And Analysis Of Binding Properties Of Calmodulin Collagen-Like Protein, Patrick P. Boddie

Honors Theses

Calmodulin is an intensely studied, intracellular, calcium-binding protein that is involved in diverse physiological processes. When bound to calcium, calmodulin undergoes a conformational change that allows it to bind specific target peptides with high affinity, one being the calmodulin binding region of myosin light chain kinase, herein called M13. This high affinity, calcium dependent association has made it a desirable choice for use in a biomaterial for drug delivery for non-steroidal anti- inflammatory drugs (NSAIDs). Two artificial genes have been designed by our lab for use in the proposed biomaterial: calmodulin collagen-like protein (CCLP), a construct composed of two calmodulin …

Targeting Metastatic Breast Cancer With Statin Drugs And Coq10, Jacob Thrasher

Honors Theses

Statin drugs are commonly prescribed to lower cholesterol levels in patients, but recently statins have been under investigation as a potential anti-cancer drug. Statins are HMG-CoA reductase inhibitors and subsequently inhibit the mevalonate pathway and cholesterol synthesis. Since cholesterol trafficking is vital in the growth and metastasis of cancer, statin drugs are being studied to explore their effects on cancer cells. CoQ10, one of the products from the mevalonate pathway, also has shown some potential anti-cancer properties, but its use to combat cancer is controversial. While some studies have shown that CoQ10 supplements can be synergistic with other cancer treatment …

Studying The Effects Of Hydrogen Bonding In 1h-1,2,3-Triazole And Its Derivatives, Leah Alexandra Wallace

Honors Theses

1,2,3-triazole is used as a building block in many pharmaceutical drugs. The molecule has several derivatives that are useful in other areas including treating fungal infections and in dealing with some environmental issues. One of its derivatives, benzotriazole, is commonly used as an inhibitor of corrosion through the formation of a copper-benzotriazole complex. One area of particular interest in studying triazoles is the ability of these molecules to tautomerize. The hydrogen atom can move from the 1H position to the 2H position and this transfer is thought to be affected by solvent interactions. Here, we study the effects of hydrogen …

Electrocatalytic Oxygen Reduction Studies On Gold Nanoparticles, Leigh Sumner

Honors Theses

After determining that the size of nanoclusters can be tuned such that they have a precise formula much like a chemical compound, much is still not known about nanoclusters, their properties, and how they interact if core size, ligand, and even environment is changed. One such mystery is how does the size of the nanoparticle tune its ability as a catalyst. As it is known that nanoparticles possess unique properties, studies have begun to look towards nanoclusters as catalysts for alternative forms of energy. Therefore, determining how size affects the ability of a nanoparticle catalyst becomes a very important question. …

Development Of A Gel Assay For Analysis Of Bovine Milk Casein, Masa Miscevic

Honors Theses

The main purpose of this research was to develop a gel assay for analysis of casein samples for ultimate application for studies of in vitro models for stomach and intestinal processing of dairy products in adults and infants. It is proposed that casein completely dissolves and is digestible in simulated gastric, and is somewhat soluble and digestible in simulated intestinal environments of adults and infants. The following experimental methods were devised to thoroughly examine behavior and properties of casein originating from different sources in range of solvents and varying pH values. First, casein was enriched in comparison to soluble materials …

Post-Translational Modification Of Hypoxia-Inducible Factor Proteins By O-Linked -N-Acetylglucosamine In Breast Cancer Cells, Sean Williamson

Honors Theses

One of the hallmarks of cancer is its ability to adapt its metabolism to survive and thrive despite needing to overcome significant energy barriers and low oxygen settings in order to do so. The hypoxia-inducible factor proteins (HIFs) play important roles in the processes in which cancer fulfills these requirements. The O-linked -N-acetylglucoseamine (O-GlcNAc) can be attached to cellular proteins through O-glycosylation, and is thus considered a potential target for anticancer mechanisms. HIFs are composed of (HIF-1 and HIF-2, respectively) and subunits. This research found that O-GlcNAc is able to attach to and modify the HIF proteins. This was accomplished …

Heterobifunctional Linear Dendritic Block Co-Polymers (Ldbcs) As Multifunctional Carriers For Targeted Drug Delivery, William Rieger

Honors Theses

Despite current research towards applications of polymeric drug delivery systems (DDSs) in biomedical research, significant limitations—specifically in synthetic accessibility, bio compatibility, and principles of molecular self-assembly—have been discerned. To address these drawbacks, we will investigate the synthesis and characterization of heterobifunctional linear-dendritic block copolymers (LDBCs), which combine the advantageous properties of both linear and dendritic blocks to afford nanomaterials with superior mechanical properties. Our LDBC systems contain two differing functional constituents, namely a hydrophilic polyamidoamine (PAMAM) dendron covalently linked to a hydrophobic polyester (polylactic acid, or PLA), and can self-assemble to form nanoparticles of various morphologies that serve as the …

An Analysis Of Commercial Oxidative Hair Dyes Using Raman Spectroscopy, Allyson Henke

Honors Theses

Here, we aim to further the potential use of surface-enhanced Raman spectroscopy (SERS) in analyzing hair dyes for use in forensic investigations. Current methods include light microscopy and thin-layer chromatography (TLC). However, these techniques can be destructive to the hair samples, do not have high discriminatory power, and have had problems with giving inconclusive results. Raman spectroscopy, on the other hand, is a fast, simple technique with a high discriminatory power. Previous work has shown that SERS can be used for in-situ analyses that is not destructive to the sample. This previous work also demonstrated that SERS could definitively differentiate …

Computational Investigation On Electronic Structures And Properties Of 4,6-Bis(Nitroimino)-1,3,5-Triazinan-2-One: An Insensitive Munitions Compound, Katarina M. Pittman

Honors Theses

In order to minimize unintentional detonation, current munitions research has focused on the development of chemical compounds that are insensitive to external stimuli whilst maintaining their effectiveness. While these compounds, known as high performance in- sensitive munitions compounds, are promising in terms of potency and stability, their envi- ronmental impacts have either not been fully understood or are yet to be investigated. In the present research, we have performed a computational chemistry investigation on electronic structures and properties of an insensitive munition compound 4,6-bis(nitroimino)-1,3,5- triazinan-2-one (DNAM). The Density Functional Theory using the B3LYP and M06- 2X functionals and MP2 methodology …

Prep-Hplc Method Development To Isolate Potentially-Carcinogenic, Arginine-Based Heterocyclic Amines, Victoria S. Kim

Honors Theses

Heterocyclic amines (HCAs) are carcinogenic molecules generated from the reaction of creatin(in)e and amino acids at high cooking temperatures in meat. Previous research has shown that replacing creatine with arginine leads to new, uncharacterized HCA molecules. This research entails implementing and optimizing the preparative HPLC analysis of extracts from multiple burnings of arginine with phenylalanine. Isolated fractions from the prep-HPLC analysis were further analyzed using the Ames test to identify mutagenic compounds. Prep-HPLC provides quality control to the burning process along with isolation of larger quantities of materials for further characterization and molecular structure identification.

Developmental Steroids And Vitamins: Identified And Quantified In Predatory Lady Beetles, Andrea Hixson

Honors Theses

Autumn brings ladybeetles into homes to seek shelter during the winter, which is a nuisance. Their bites may induce an allergic reaction resulting in painful rashes. Predatory ladybeetles have been used as a biological control agents. Not only do they feed on ecological pests, they also feed on the saps of ripe fruits reducing the value of the damaged crop. Two species of ladybeetles (Coleoptera: Coccinellidae) will be examined to determine the quantities of steroids and vitamins used throughout their life stages. The species examined are native, Hippodamia convergens, of North America, and an invasive, Harmonia axyridis, of Asia. The …

The Clean Air Act And Its Impact On Ground Level Ozone Pollution Levels In Los Angeles, California, Rebecca G. Ford

Honors Theses

Ozone (O₃) occurs naturally as a protective, ultraviolet radiation-shielding “Ozone Layer” in the Stratosphere and as a photochemically produced pollutant in the Troposphere. The Clean Air Act (CAA) of 1970 regulates the emission and concentration of O₃ and five other atmospheric pollutants. Since the signing of the CAA, the ongoing question has been whether or not the National Ambient Air Quality Standards (NAAQS) and regulatory policies have had an effect on decreasing O₃ concentration. The Los Angeles metropolitan area is a prime example of how O₃ can be a public health hazard, and taint a …

Octahedral Ruthenium(Ii) Complexes For C-H Bond Activation And Olefin Hydroarylation, Patrick Z. Zdunek

Honors Theses

The study of inert C-H bond activation of hydrocarbons has been gaining interest. As these hydrocarbons are used in the production of many consumables such as fuel, plastics, and detergents, it is necessary to efficiently utilize the finite quantity of petroleum feedstocks. Transition metal complexes are incorporated as catalysts into synthetic routes to create new C-X (X = C, N, O) bonds in order to increase the chemical value of organic molecules. The complex [Ru(η6-p-cymene){P(OCH2CF3)3}(Ph)(OTf)] (1) (P{OCH2CF3}3 = tris(2,2,2-trifluoroethyl) phosphite, Ph = phenyl, OTf = trifluoromethanesulfonate) was prepared and tested for functionality as a catalyst in olefin hydroarylation. Catalytic reactions …

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 …

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 …

Extraction Studies Of Toxic Multiply Charged Oxoanions From Aqueous Media Using Nanojars, Hartman Christian

Honors Theses

In this paper, the potential of nanojars as extracting agents of chromate and arsenate from aqueous media into a non-polar organic medium is investigated. Nanojars are a class of compounds that consist of multiple [cis-CuII(μ-OH)(μ-pz)]n cyclic polymerization isomers (n = 6, 8, 9, 10, 12, 14; pz = pyrazolato anion) that form from self-assembly reactions around a multiply-charged oxoanion core with capping counterions to render an overall neutral complex. This incarcerates the anion, preventing it from escaping the complex without the use of any covalent bonding, making it a potentially highly effective and unique extracting agent. We have concluded that …

Molecular Mass Of L-Arginine-Based Potentially Carcinogenic Heterocyclic Amines, Irene S. Hwang

Honors Theses

Investigation of cancer-inducing molecules in cooked foods has led to the discovery of mutagenic heterocyclic amines (HCAs) in meat. The amino acids creatin(in)e and L-phenylalanine form the precursors for these HCAs. Recent research here at Andrews University have found similar mutagenic HCAs produced from plant-based proteins when L-arginine, rather than creatin(in)e, is substituted in high temperature reactions (simulated cooking) with L-phenylalanine. Our research focused on developing HPLC methods to isolate individual candidates that are then screened for mutagenicity via the Ames test. Mass spectroscopy methods were also developed to identfy the molecular structure of these lead mutagenic L-arginine-based HCAs.

Fluorescence Analysis Of Pamam Dendrimers, Ansel Nam

Honors Theses

Despite their lack of conjugation, polyamidoamine (PAMAM) dendrimers are intrinsically fluorescent, and this fluorescent is somewhat manipulable through altering the dendrimer's solvent. This level of fluorescence is dependent on a number of the dendrimer's qualities: the pH of the solvent, the mass percent concentration of the dendrimer in solvent, and the generation size of the dendrimer. In past studies, fluorescent intensity increased as generation size increased and pH decreased. Thus, this research project will attempt to replicate those results as well as further analyze the efficiency of fluorescence of PAMAM dendrimer in comparison to fluorescein.