Chemistry Commons^™

An Evaluation Of Elemental Composition Of Soils Associated With Ground Nesting Ants In The Family Formicidae In Somerset County, Maine, Haley H. Depner

All Student Scholarship

Ants are keystone organisms and engineers in many ecosystems, playing an important role in nutrient cycling and rearrangement of organic and inorganic materials through foraging, waste management and, in subterranean species, nest construction and maintenance. In this study, I conducted elemental analysis of soils for calcium, copper, iron, potassium, manganese and zinc in and around the colonies of subterranean nesting ants. The two-step analysis used in this study utilizes the efficiency of X-Ray Fluorescence (XRF) Spectrometry to look for overall trends in elemental composition followed by Flame Atomic Absorbance (AA) to achieve higher resolution of select elements of interest as …

Growth, Lipid Production And Biodiesel Potential Of Chromulina Freiburgensis Dofl., An Acidophilic Chrysophyte Isolated From Berkeley Pit Lake, June E. Mohler Mitman

Graduate Theses & Non-Theses

Microalgae remain a promising, but underdeveloped source of lipids for sustainable biodiesel. Some of the obstacles to cost-effective commercial-scale production have been culture contamination and expensive harvest methods. A chrysophyte isolated from Berkeley Pit Lake and identified as Chromulina freiburgensis, was found to grow rapidly in a pH 2.5 liquid medium and to amass numerous intracellular lipid bodies. This research addresses the scarcity of published knowledge on the topic of chrysophyte species as potential lipid sources for biodiesel. It investigates how growth phase, culture conditions, and harvest timing influence the quantity and composition of lipids produced by this alga. …

Investigating The Kinetics Of Clay-Catalyzed Conversion Of Anthracene To Prebiotically Relevant 9,10-Anthroquinone, Hope Juntunen

Masters Theses & Doctoral Dissertations

The presence polycyclic aromatic hydrocarbons (PAHs) on the primordial Earth can be attributed to carbonaceous meteorites bombarding planetary surfaces. Subsequently, the PAHs reacted with catalytic clay mineral surfaces to produce quinones that functioned as electron transporters in emergent biological systems. To address this hypothesis, we assessed the kinetics of anthracene (ANTH) conversion to 9,10-anthraquinone (ANTHQ) in the presence of montmorillonite and kaolinite clay (MONT and KAO, respectively) over the temperature range 25 to 250 oC. Apparent rates of conversion were concentration independent and displayed a sigmoidal relationship with temperature, and conversion efficiencies ranged from 0.027 to 0.066%. Conversion was not …

Development Of Acceptor-Integrated Crystalline Organic Materials, Brandon Yarbrough

Theses and Dissertations

We report the first example of fullerene-containing porous covalent-organic scaffold, which combines not only crystallinity and porosity, but also integrates the intrinsic properties of a redox-active buckyball, along with the ability to tune electronic properties. Thus, the presented studies not only demonstrate the possibility of merging the strong electron accepting properties of fullerene-based derivatives with the versatility of covalent-organic frameworks (COFs), but also begin the class of crystalline, entirely organic, donor-acceptor fullerene COFs through covalently modifying the channel walls. These studies could foreshadow new avenues for buckyball utilization for applications ranging from organic photovoltaics to molecular electronics.

1 H, 13 C, And 15 N Resonance Assignments Of The C-Terminal Lobe Of The Human Hect E3 Ubiquitin Ligase Itch, Steven A. Beasley, Roela Bardhi, Donald E. Spratt

Chemistry

ITCH (aka Atrophin-1-interacting protein 4) is a prominent member of the NEDD4 HECT (Homologous to E6AP C-Terminus) E3 ubiquitin ligase family that regulates numerous cellular functions including inflammatory responses through T-cell activation, cell differentiation, and apoptosis. Known intracellular targets of ITCH-dependent ubiquitylation include receptor proteins, signaling molecules, and transcription factors. The HECT C-terminal lobe of ITCH contains the conserved catalytic cysteine required for the covalent attachment of ubiquitin onto a substrate and polyubiquitin chain assembly. We report here the complete experimentally determined 1 H, 13 C, and 15 N backbone and sidechain resonance assignments for the HECT C-terminal lobe of …

Survey Of Chemistry I, Anne Parker, Farooq Khan, Victoria Geisler, Douglas Stuart

Chemistry Grants Collections

This collection of the grant proposal, syllabus, and final report for Survey of Chemistry I at University of West Georgia was created under a Round 12 Transformation Grant.

Charge-Transfer Or Excimeric State? Exploring The Nature Of The Excited State In Cofacially Arrayed Polyfluorene Derivatives, Ainur Abzhanova, Lena V. Ivanova, Denan Wang, Tushar S. Navale, Sameh H. Abdelwahed, Maxim Vadimovich Ivanov, Sergey V. Lindeman, Rajendra Rathore, Scott A. Reid

Chemistry Faculty Research and Publications

It is well known that upon electronic excitation various π-stacked dimers readily exhibit excimer formation, facilitated by a perfect sandwich-like arrangement between the chromophores. However, it is unclear whether such a dimer is also capable of electron transfer upon excitation, if a strong electron-donating group is covalently attached. In this work, we probe the nature of the excited state in a series of cofacially arrayed polyfluorene derivatives with electron-rich aromatic donor attached via a methylene linker. Our studies show that in all cases excimer formation is energetically favorable, and promotion of a charge-transfer state in such systems is possible but …

Human Serum Albumin Nanoparticles For The Treatment Of Hepatocellular Carcinoma, Mina Hibino

Senior Honors Theses

Hepatocellular carcinoma (HCC) is an aggressive and destructive cancer of the liver. Currently available treatment plans are locoregional therapies aimed to decrease tumor burden, resection that surgically removes the tumor, or systemic therapies for advanced stage to extend survival. However, decompensation post-locoregional treatment and recurrence rates for HCC remain high despite the different treatment modalities. There is a great need for alternative and more effective treatment methods that will further dampen tumor burden while decreasing the risk of intra- and extrahepatic spread. The goal of this project was to develop a non-invasive therapeutic treatment to target HCC cells using human …

Development Of Nanomaterial Supports For The Study Of Affinity-Based Analytes Using Ultra-Thin Layer Chromatography, Allegra Pekarek

Department of Chemistry: Dissertations, Theses, and Student Research

Ultra-thin layer chromatography (UTLC) is a growing field in analytical separations. UTLC is a branch of planar and liquid chromatography that is related to thin layer chromatography. The main advantage of UTLC compared to other techniques is it uses much less material, allowing for faster and more sensitive separations to take place. The UTLC devices fabricated in this project used either silicon oxide or silicon nanopillars deposited on a glass slide using glancing angle deposition (GLAD). Even a thin layer of these nanopillars deposited on a glass slide provide a large surface area for the analyte to be separated. GLAD …

Analysis Of Drug–Protein Interactions During Diabetes By High-Performance Affinity Chromatography, Pingyang Tao

Department of Chemistry: Dissertations, Theses, and Student Research

High-performance affinity chromatography (HPAC) is a type of liquid chromatography in which solutes are separated based on their binding to a stationary phase that is a biologically-related agent. Sulfonylurea drugs have significant binding to proteins in blood, with most of this binding is believed to occur with human serum albumin (HSA). HSA is known to be modified as a result of the high serum levels of glucose that is present during diabetes, which may also alter the function of HSA as a binding agent for many drugs in circulation. Some modifications of HSA that can occur during diabetes involves early …

A Quantitative Lc-Ms/Ms Method For Determination Of A Small Molecule Agonist Of Epha2 In Mouse Plasma And Brain Tissue, Bo Zhong, Yaxin Li, Nethrie Idippily, Aaron Petty, Bin Su Ph.D., Bingcheng Wang

Chemistry Faculty Publications

Compound 27 {1, 12‐bis[4‐(4‐amino‐6,7‐dimethoxyquinazolin‐2‐yl)piperazin‐1‐yl]dodecane‐1,12‐dione} is a novel small molecule agonist of EphA2 receptor tyrosine kinase. It showed much improved activity for the activation of EphA2 receptor compared with the parental compound doxazosin. To support further pharmacological and toxicological studies of the compound, a method using liquid chromatography and electrospray ionization tandem mass spectrometry (LC–MS/MS) has been developed for the quantification of this compound. Liquid–liquid extraction was used to extract the compound from mouse plasma and brain tissue homogenate. Reverse‐phase chromatography with gradient elution was performed to separate compound 27 from the endogenous molecules in the matrix, followed by …

The Effects Of Organic And Inorganic Nanoparticles On Bacterial Deactivation, Lauren Cooper

Mahurin Honors College Capstone Experience/Thesis Projects

Antibacterial resistance is one of the greatest problems in modern medicine, as healthcare professionals are experiencing more and more difficulty in providing effective care. As such, alternative methods of treatment are needed in order to overcome this issue. One recently proposed method of alternative treatment is photodynamic therapy. Photodynamic therapy is a light-based method of treatment that utilizes (1) a photosensitizing agent, (2) light, (3) produced oxygen species. When the photosensitizing agent is injected into an infected region of interest and then irradiated with a certain wavelength of light, the agent is photoactivated and begins to produce harmful forms of …

Analysis And Review Of The Effects Of Bacterial Competition On Efflux Pump Inhibition, Robert Leszcynski

Honors Theses

Multidrug resistant antibacterial strains are a dangerous problem for modern medical professionals. When cells of two different strains are grown together, they must compete with each other for nutrients. This competition can lead to the production of harmful compounds that are toxic to the competing strain. One such compound may be a compound that inhibits the efflux of antibiotics from the cell. When the cells compete with one another, one or both of the cells will produce compounds that are harmful to the competing strain.

Tracking Disparate Colony Morphological Trends With Thermus Scotoductus, Matthew P. Leverick

Honors Theses

When plating most mesophilic bacteria, the colony shape, size, and color tends to be uniform when a single strain is present. When plating defined cell densities of T. scotoductus, however, the colonies were not of uniform size and shape while it grew on the surface. In this project, we sought to observe trends in colony morphology (shape and size) changes using the thermophile Thermus scotoductus on nutrient rich agar plates at 60°C. A general planktonic growth curve was also created to help characterize the activity of this bacterium. This project was our first attempt to characterize if this unusual phenomenon …

Boron Dipyrromethenes: Synthesis And Computational Analysis, Eduardo Rivé Lockwood

Honors Theses

Recently, there has been a growing interest in the boron dipyrromethene (BODIPY, 4,4′- difluoro-4-bora-3a,4a-diaza-s-indacene) compounds. BODIPY compounds have fascinating properties that allow for the absorption and emission of light in the near infrared region of the electromagnetic spectrum. These molecules are highly modifiable making them ideal chemicals for the use of photoelectric energy conversion such as for commercial use in dye sensitized solar cells (DSSCs). It has been previously shown that different meso compounds have only a slight effect on the absorptive capabilities of these BODIPY compounds. We believe that the BODIPY compounds’ lack of planarity is one of the …

Identifying Natural Inhibitors Of Bacterial Efflux Pumps, Marrisa Therriault

Honors Theses

Antibiotic resistance is a constantly progressing epidemic. Many strains of bacteria have developed a resistance to antibiotics, resulting in prolonged sickness and death. Resistance can be to a specific drug (single drug resistance) or to multiple drugs (multi-drug resistance). This resistance can be caused by a tripartite protein pump called an efflux pump that extends through the inner and outer membranes of the bacterium to pump antibiotics from the inside of the cell to the extracellular environment. In E. coli the efflux pump is called AcrAB-TolC. In the efforts to combat this problem, this experiment focuses on the inactivation of …

Structural Studies Of Dna Repeats Implicated In Cancer, Deondre Jordan , '19

Senior Theses, Projects, and Awards

DNA replication is an essential process for the survival of all organisms. Errors can occur during the process that leads to replication stress, which can promote genomic instability, a hallmark of cancer. The Brown lab conducted a genome wide study to identify sites and sequences linked to replication stress. Tandem DNA repeats comprised the sequences identified in this study. One particular DNA repeat (CAGAGG)ₙ stood out due to being highly associated with replication stress. Repeats such as (CAGAGG)ₙ are believed to fold into fold into intramolecular structures that physically block DNA polymerase during replication. Understanding the structures of these problematic …

Diastereoselective Synthesis Of Cyclopentenes Via Rhii-Catalyzed C-H Insertion Directed By A Planar Chiral N-Oxazolidinoyl Iron(0) Tricarbonyl Diene Complex, Benjamin G. Hejna , '19

Senior Theses, Projects, and Awards

Herein is presented a general methodology for the synthesis of cyclopentenes bearing two consecutive, diastereoselectively generated stereocenters by Rhᴵᴵ-catalyzed C-H insertion using a planar chiral N-oxazolidinoyl iron(0) tricarbonyl diene complex as a steric directing group. The majority of this work is dedicated to designing and accessing viable substrates to undergo the aforementioned diastereomerically selective C-H insertion, as well as determination of the absolute stereochemical configuration of the enantiomerically pure product. We hypothesize that the observed stereochemical outcome is caused by the favorability of orienting the substituent on each newly-generated stereocenter away from the sterically bulky iron(0) tricarbonyl fragment. In …

Synthesis And Characterization Of Tripodal Tris(Nitroxide) Aluminum, Gallium, And Indium Complexes, Audra J. Woodside , '19

Senior Theses, Projects, and Awards

One important challenge in green chemistry is the development of safe and sustainable catalytic systems for molecular transformations that do not rely on precious metals. In this vein, I explore how one can expand the utility of aluminum complexes. Aluminum is a prime choice for such catalytic development as it is relatively inexpensive (less than $2/kg), readily available, and non-toxic. Although there are ample examples of aluminum complexes acting as Lewis-acid catalysts, the lack of readily accessible multielectron redox states leaves aluminum complexes inept in redox-based transformations. In order for aluminum complexes to be used in redox reactions, I prepared …

Synthesis And Structural Analysis Of Macrocyclic Arenes: Experimental And Computational Insights, Saber Mirzaei

Master's Theses (2009 -)

Synthesis, properties and applications of macrocyclic molecules have been one ofthe interesting branches of organic chemistry during the past century. Several classes ofmacrocyclic molecules, based on their repeating unit and connectivity pattern, have beendiscovered. Macrocyclic arenes, cyclo[n]veratrylenes, calix[n]arenes and pillar[n]arenes,were among the most interesting and studied molecules. The major difference betweenthese molecules is the methylene-bridged connectivity pattern. In the present thesis, Iattempted to synthesize these molecules using novel approach which has been developedin our group and performing some structural analysis using experimental andcomputational techniques.The first synthesized and investigated molecule is the …

Multi-Instrument Surface Characterization Of Display Glass, Cody Vic Cushman

Theses and Dissertations

Flat panel displays (FPDs) are microfabricated devices that are often fabricated on specialized glass substrates known as display glass. The surface chemistry of the outer few nanometers of display glass can have an important influence on FPD performance and yield. Dsiplay glass surface characterization is difficult because (i) display glass surface composition varies significantly from its bulk composition; (ii) high-surface area forms of glass, such as fibers and powders, may not have the same surface composition as melt-formed planar surfaces, and (iii) the surface composition of display glass may be altered through exposure to chemical treatments commonly used during flat …

Design And Synthesis Of Simplified Analogs Of The Natural Product Sordarin As Potential Antifungal Agents, Yibiao Wu

Dissertations (1934 -)

Invasive fungal infection is a life-threatening illness that causes high mortality, and is especially common among patients with compromised immune systems. However, currently there are only three major classes of clinically useful drugs capable of treating such infections. In addition, due to the fact that drug resistance has become a serious issue especially among patients who suffer from chronic infections, it is urgent to identify new drug candidates, particular those of new classes. The discovery of the natural product sordarin and its novel mechanism of action of inhibiting fungal protein synthesis via the fungal eukaryotic elongation factor 2 (eEF2) led …

Monitoring Silver Nanoparticle Aggregation In Situ By Integrating Particle Impact Voltammetry And Uv-Vis Spectroscopy, Laela Ezra , '19

Senior Theses, Projects, and Awards

Engineered nanomaterials (ENMs) have been increasingly used for a variety of purposes. Silver nanoparticles (AgNPs) are the most widely-used ENM to date. AgNPs undergo many transformations while in solution and in biologically relevant environments, so the development of techniques to analyze the extent of these transformations is crucial. The transformation of interest for this work is AgNP aggregation. There exist techniques to monitor aggregation of AgNPs and other ENMs (such as scanning electron microscopy) but often these instruments cannot measure aggregation in situ: some cannot monitor aggregation in real-time, and none are suited for fieldwork. Two methods that can characterize …

Diastereoselective Cyclizations Of Enantiopure Planar Chiral N-Oxazolidinoyl Diene Iron(0) Tricarbonyl Complexes, Colin C. Howell , '19

Senior Theses, Projects, and Awards

Iron(0) tricarbonyl diene complexes have long been established as effective stereodirecting groups due to their planar chirality and the steric bulk of the iron fragment. If initial diastereoselective complexation can be achieved, these molecules are therefore capable of acting as scaffolds for the stereoselective synthesis of architecturally complex products. The Paley laboratory uses chiral auxiliaries, most recently oxazolidinones, bound to acyclic dienes to assure diastereoselective complexation, before exploring the potential of diverse diastereomeric chemistry on the diene periphery. In this work we report progress on the development of an asymmetric, intramolecular rhodium(II)-catalyzed C-H insertion adjacent to the diene to form …

Site-Directed Spin Label Epr Studies Of The Interaction Between The Influenza A Proteins (M1 And M2) Involved In Viral Assembly, Abigail J. Wong-Rolle , '19

Senior Theses, Projects, and Awards

Influenza A presents a significant concern for public health as it is the cause of seasonal outbreaks and global pandemics. The influenza A proteins, matrix protein 1 (M1) and matrix protein 2 (M2), have been shown to be essential for the propagation of new viruses, especially through their roles in viral assembly and budding. The M2 cytoplasmic tail interacts with the M1 protein, recruiting it to the viral budding site and enabling proper packaging of the viral genome. The Howard lab has previously characterized residues 50-70 in the M2 cytoplasmic tail and the M2 protein’s conformational equilibria by sitedirected spin …

Emergent Properties And Applications Of Self- Assembled Benzophenone-Containing Materials, Baillie A. Dehaven

Theses and Dissertations

Supramolecular assembly of benzophenone through urea hydrogen bonding interactions facilitates the formation of remarkably persistent triplet radical pairs upon UV-irradiation at room temperature, whereas no radicals are observed in solution. The generation of organic radicals is correlated to the microenvironment around the benzophenone carbonyl, the types of proximal hydrogens, and the rigid supramolecular network. High-Field EPR and variable temperature X-band EPR accompanied by simulations suggest a resonance stabilized radical pair through hydrogen abstraction. Previous work has shown that UV-irradiation of self-assembled benzophenone bis-urea host results in low quantities of radical pairs that can be used to enhance NMR signals …

Impact Of Glutathione Transporters On Subcellular Glutathione Pools And Cell Survival In Saccharomyces Cerevisiae, Crystal Conaway Mcgee

Theses and Dissertations

Thiol-disulfide redox homeostasis is integral for maintaining the redox status of proteins and other thiol-containing molecules within cells. Mitochondria are particularly vulnerable to disruptions in redox balance, due to production of reactive oxygen species (ROS) during oxidative metabolism. Among the many antioxidants and detoxifying enzymes existing in mitochondria, glutathione (GSH) has proven to be critical for the preservation of function and structural integrity of the organelle. Therefore, our studies are aimed at elucidating the factors that control mitochondrial GSH metabolism in the model eukaryote Saccharomyces cerevisiae (baker’s yeast). A critical component of understanding subcellular GSH homeostasis is identifying routes of …

Sustainable Polymers And Antimicrobial Biomaterials From Multicyclic Natural Products, Md Anisur Rahman

Theses and Dissertations

In this dissertation, the development of sustainable polymers and antimicrobial biomaterials from multicyclic natural products is illustrated. In Chapter 1, an overall background and recent development of sustainable polymers from natural product-based renewable biomass, antimicrobial biomaterials, and polymerization methods are introduced. Afterward, the primary research objectives of my doctoral research work are illustrated.

In chapter 2, designing block copolymer architectures toward tough bioplastics from renewable natural rosin was described. One of the most abundant natural biomasses is resin acids, however, most of the polymers derived from resin acids are brittle because of their bulky hydrophenanthrene pendant group. To overcome the …

Anion Pool Directed Electroorganic Synthesis, D.M.M. Madushanka Mevan Dissanayake

Theses and Dissertations

The “Anion pool” approach introduces a greener approach for derivatization of pharmaceutically important molecules by amalgamating both electrochemistry and organic synthesis. This is a base and metal free procedure carried out in organic solvents recommended for pharmaceutical preparations. The anion pool procedure generates reactive nitrogen nucleophiles in situ via electrochemical reduction of heteroaromatic substrates. The adoption of such a methodology prevents generation of waste from bases used for deprotonation. Hydrogen is the main by-product of generation of anion pool, which, if produced at a large enough scale could be used as a renewable fuel. These attributes comply with the principles …

Development Of Nickel Catalyzed Cross-Coupling Methodologies, Ryan J. Key

Theses and Dissertations

In this work, we have addressed some of the issues surrounding catalytic crosscoupling reactions by using a nickel terpyridine catalyst, [Ni(tpy)(py)(CH3CN)2](PF6)2 in the Buchwald-Hartwig amination reaction and a functionalized variant, [(2,2':6',2''- terpyridine-4'-benzoic acid)Ni(II)]Cl2 on SiO2, in Suzuki coupling. These processes are unique in the approaches taken to achieve reactivity. In the Buchwald-Hartwig amination reaction, we used photoredox dual catalytic methods to achieve a sustainable approach to generate secondary and tertiary amines. This report is unique in many ways; most importantly, this method uses N-centered radicals to generate new C-N bonds. This report is also the first report to show generation …