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Molecular Design And Patterning Of Biosurfaces On Poly(Tetrafluoroethylene) (Ptfe), Nattharika Aumsuwan

Dissertations

This dissertation describes the design, synthesis, and development of biocompatible poly(tetrafluoroethylene) (PTFE) surfaces that exhibit anti-microbial, anticoagulant, and dual functional surface properties. It consists of two parts: (1) design, synthesis, and analysis of antimicrobial and anti-coagulant PTFE surfaces, and (2) controllable micropatterning of anti-microbial and anti-coagulant species on the surface. PTFE was modified by Ar microwave plasma reactions in the presence of maleic anhydride, which upon hydrolysis creating COOH groups. These COOH primers were utilized as a platform for further surface reactions to attach polyethylene glycol (PEG) spacers, and penicillin (PEN) or ampicillin (AM) onto the PTFE surfaces. The use …

Aqueous Raft Synthesis Of Stimuli-Responsive, Amphiphilic Block Copolymers And Self-Assembly Behavior In Solution And Incorporation Into Lbl Films, Matthew Grady Kellum

Dissertations

Of all the living radical polymerization techniques, reversible addition– fragmentation chain transfer (RAFT) polymerization is arguably the most versatile in terms of the reaction conditions (e.g. temperature and solvent selection), monomer selection (e.g. neutral, anionic, cationic, and zwitterionic), and purification. Since the introduction of RAFT in 1998, the McCormick research group and others including the Lowe, Sumerlin, and Davis research groups have synthesized a wide range of (co)polymers with predetermined molecular weights, low polydispersities, and advanced architectures utilizing aqueous RAFT (ARAFT) polymerization. These research groups have also studied how various block copolymers exhibit stimuli-responsive behavior due to a change in …

Multi Stimuli-Responsive Copolymers Obtained From Colloidal Dispersions, Fang Liu

Dissertations

This dissertation describes the design, synthesis, and development of multi stimuli-responsive random copolymers that exhibit collective responsiveness to temperature, pH or electromagnetic radiation. New colloidal particles of poly(N-(DL)-(1- Hydroxyymethyl) propylmethacrylamide/n-butyl acrylate) (p(DL-HMPMA/nBA) and poly(2-(N,N′-dimethylamino)ethyl methacrylate/n-butyl acrylate) (p(DMAEMA/nBA)) were synthesized, which upon coalesce to form solid continuous films. The presence of lower glass transition (Tg) nBA components not only facilitate film formation, but also provide sufficient free volume for polymer chain rearrangements. These studies showed that coalesced films exhibit 3D dimensional changes upon external stimuli, which are attributed to the collapse and conformational changes of stimuli-responsive components as well as buckling …

Developing A Biosensor For The Detection Of Bacteria: A Comparison Of Methods For Isolating Bacteria-Specific Antibodies, Scott Allen Walper

Dissertations

The antigen-antibody interaction is known to be a high affinity and highly specific interaction that can readily be used for the detection and identification of biological and chemical agents. These studies were conducted to develop an efficient and cost-effective method of obtaining bacteria-specific antibody molecules for integration into a fielddeployable biosensor. Antigen-binding molecules were obtained both as full-length IgG molecules from a hybridoma cell line and as recombinant single-chain Fv (scFv) antibodies isolated from naïve and immunize libraries. Monoclonal and recombinant antibody systems were compared on the effectiveness of producing new, target-specific molecules; the efficiency of production and purification of …

A Study Of The Effective Interfacial Tension Between Miscible Fluids By Spinning Drop Tensiometer And Microfluidics, Gloria Dollie Viner

Dissertations

A miscible system is a system in which two fluids can completely dissolve in one another. A sharp concentration gradient can be observed in miscible systems. We studied the concentration gradient or miscible interface between IBA (isobutyric acid) and water, a miscible system near a consulate point (close to the system’s upper critical solution temperature [UCST]). The original hypothesis was that the sharp concentration gradient of IBA/water was due to barodiffusion, a diffusion effect driven by pressure. We tested this hypothesis by studying IBA/water at five different rotation rates and three different temperatures. At 20 oC, increasing rotation acceleration from …

Comparison Of Rna Quality From Stressed And Unstressed Recombinant Escherichia Coli, Mary Alice Salazar

All Theses

High quality, intact RNA is required for DNA microarray studies, cloning, and reverse transcriptase polymerase chain reaction (rt-PCR) analysis. There are several analytical methods used to assess the RNA quality. The RNA Integrity Number (RIN) from the Agilent Bioanalyzer is one quality control assay used to evaluate RNA. For recombinant Escherichia coli cultured under stressful conditions the RNA profiles obtained using the Agilent Bioanalyzer indicate RNA degradation; however, RNA obtained and purified in parallel from unstressed recombinant cultures indicate acceptable RNA values without significant degradation. We proposed that for stressed E. coli the RIN value is not necessarily indicative of …

Synthesis Of Meta-Terphenyl Scaffolded Molecules For Catalysis And Sensor Applications, Brad Morgan

All Dissertations

The utility of the m-terphenyl has been observed in a wide variety of applications since its first discovery. The tunable conformational flexibility contributes to the unique properties and resulting applications thereof. Chapter 1 goes into detail about the concepts used throughout and defines the tools needed to understand the chemistry in the
resulting chapters.
The primary use of the m-terphenyl herein is as a canopy that shields a pocket created underneath the central ring. Functionalization within this pocket allows metal binding in defined coordination environments. with the use of donor ligands attached to the flanking rings. The applications of these …

Diffusion Monte Carlo Studies Of Quantum Solvation: Finding Nodal Functions Of Wavefunctions Using A Genetic Algorithm, Christina Hansen Howell

Undergraduate Honors Capstone Projects

Solvation is important in many chemical reactions since most reactions occur in solution. Recently, progress has been made using helium-4 nanodroplets as the solvent at temperatures close to absolute zero. Because helium-4 is a superfluid it solvates dissolved molecules much differently that does a conventional solvent. This opens up the possibility of performing new types of chemistry in the superfluid environment. However, the nature of the interaction of the dissolved species with the solvent remains poorly understood. The basic question to be answered in this project is: how does the quantum solvent perturb the rotational dynamics of the solute particles? …

Preparation And Characterization Of Extraction Chromatography Resins Using N-Donor Extractants For Trivalent Actinide And Lanthanide Separations, Christopher L. Klug

UNLV Theses, Dissertations, Professional Papers, and Capstones

Actinide and lanthanide elements exist in the geosphere and biosphere due to both natural abundances and anthropogenic activities. The investigation of the presence and transport of actinides through the environment is of great scientific interest. In order to prepare environmental samples for precise measurements, the individual actinides must be separated from the chemically similar lanthanides, and from neighboring actinides. Existing extraction chromatography resins are either poorly suited for this separation, have bleeding problems, are not reusable, or fail the CHON principle. In an effort to resolve these issues, malonamides and N-donor extractants from the BTP and BTBP classes of solvent …

Self-Assembly Of Architecturally Complex Block Copolymers, Juan Hinestrosa

All Dissertations

The term self-assembly denotes the formation of complex structures from simpler building blocks, resembling the manner in which Nature generates functional systems. In this pursuit, block copolymers present a great opportunity to study the interactions, dynamics and self-assembly of soft matter. Block copolymers have the ability to self-assemble into thermodynamically stable microphase segregated domains of precise shape and size, which are controlled by the chemistry of the constituent blocks, their size and connectivity, temperature and solvent conditions. Specifically, in this body of work two different types of branched copolymers with polystyrene (PS) and polyisoprene (PI) constituents are studied. The complex …

Chemical Characterization Of Botanical Products: Comprehensive Speciation By Liquid Chromatography Particle Beam Mass Spectrometry, Joaudimir Castro Georgi

All Dissertations

The dietary supplement industry has expanded and many of these supplements have become an important aspect of people's everyday lives. In 1994, the U.S. Dietary Supplement Health and Education Act (DSHEA) classified numerous nutraceutical/botanical products as dietary supplements because of their beneficial medicinal properties and provided the necessary regulation to the supplement producers. Since then, the interest of the scientific community towards dietary supplements has grown intensively and numerous studies have been carried out in order to understand the chemical behavior of the active molecules in the human body. The development towards analytical methods for the quantification of the active …

Designing Molecular And Nanoscale Materials For Environmental Chemistry Processes, Wen Guo

Dissertations

This dissertation focuses on fundamental studies to identify materials that detect and degrade common organic environmental pollutants. Chapter 1 represents the overview of two widespread ground water contaminants: organohalides and organophosphorous compounds. Due to continuous usage of these compounds as well as their toxicity, reliable and sensitive methods for their detection and degradation are urgently needed. In Chapter 2 a description of molecular sensors designed with high sensitivity and selectivity to detect and distinguish between three organophosphorus (OP) pesticides are described. These sensors provide dual optical and electrochemical signals for detection, which minimizes false-positives. The signal transduction occurs in real …

Characterization Of The N-Terminal Domains And Disease-Causing Mutations Of The Human Wilson Protein, Joshua Mutambuki Muia

Dissertations

The Wilson protein (ATP7B) is a copper transporting ATPase that is involved in copper trafficking and homeostasis. Unlike the other known P-type ATPases, it possesses six homologous metal binding domains at the N-terminal end. Several mutations in the gene coding for this protein lead to Wilson disease, a hepatic disorder characterized by impaired excretion of copper in the bile, and accumulation of copper in body organs such as the liver, brain, kidney, and eye cornea. Characterization of various regions of expressed and purified ATP7B has been hampered by its low stability, aggregation and degradation.

In this research, novel methods were …

Nanostructured Poly(3,4-Ethylenedioxythiophene)–Metalloporphyrin Films: Improved Catalytic Detection Of Peroxynitrite, Serban Peteu, Pubudu Peiris, Ermias Gebermichael, Mekki Bayachou

Chemistry Faculty Publications

We investigated in this paper the sensing performance of inherently conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), functionalized with hemin (iron protoporphyrin) as an electrocatalytic reporter. The sensing platform is prepared by electrodeposition of a composite film of hemin–PEDOT on a 30-μm diameter carbon fiber electrode (CFE). The polymerized films were characterized by field emission scanning electron microscopy (FESEM), which pointed to nanostructured films with tortuous pores. The electrocatalytic oxidation of peroxynitrite was characterized by cyclic voltammetry as well as other electrochemical methods. The catalytic current is proportional to the analyte's concentration. Optimized hemin–PEDOT modified CFEs were utilized for the first time to …

Ribosomal Rna Mutations That Inhibit The Activity Of Transfer-Messenger Rna Of Stalled Ribosomes, Jacob N. Crandall

Theses and Dissertations

In eubacteria, stalled ribosomes are rescued by a conserved quality-control mechanism involving transfer-messenger RNA (tmRNA) and its protein partner SmpB. Mimicking a tRNA, tmRNA enters stalled ribosomes, adds Ala to the nascent polypeptide, and serves as a template to encode a short peptide that tags the nascent protein for destruction. To further characterize the tagging process, we developed two genetic selections that link tmRNA activity to cell death. These negative selections can be used to identify inhibitors of tagging or to identify mutations in key residues essential for ribosome rescue. Little is known about which ribosomal elements are specifically required …

Cadmium, Copper, Iron, And Zinc Concentrations In The Kidneys Of Grey Wolves (Canis Lupus) From Alaska, Idaho, Montana, And The Northwest Territories, Susan Blunck, Emily Jones, Kelly Petersen, Given Harper, Facutly Advisor, Jeffrey Frick, Faculty Advisor

John Wesley Powell Student Research Conference

No abstract provided.

Imaging The Topography And Monitoring The Electrochemical Activity Of Biological Samples, Erica Woodall, Emma Dewalt, Faculty Advisor, Melinda Baur, Faculty Advisor

John Wesley Powell Student Research Conference

No abstract provided.

Development Of A Discovery Laboratory To Observe And Quantify Protein Denaturation And Coagulation In Egg White Albumin, Elizabeth Ave Maria, Melinda Baur, Faculty Advisor

John Wesley Powell Student Research Conference

No abstract provided.

Electrochemical Assay Of Specific Biological Compounds Using Scanning Electrochemical Microscopy, Thomas Marlow, Aaron Moore, Melinda Baur, Faculty Advisor

John Wesley Powell Student Research Conference

No abstract provided.

An Expeditious Synthesis Of N-Substituted Pyrroles Via Microwave-Induced Iodine-Catalyzed Reactions Under Solventless Conditions, Debasish Bandyopadhyay, Sanghamitra Mukherjee, Bimal K. Banik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

An expeditious synthesis of N-substituted pyrroles has been developed by reacting 2,5-dimethoxy tetrahydrofuran and several amines using a microwave-induced molecular iodine-catalyzed reaction under solventless conditions.

Dihydropyran Formation By A Two Step Process, James Zachary Wright

Undergraduate Honors Thesis Collection

The 2, 6-disubstitued dihydropyran is produced by a two step process, involving a Suzuki Miyaura Cross Coupling reaction followed by anintramolecular ring closing Michael Addition reaction. In this project a vinyl boronic acid, 6-(2-phenylethenyl)-2-hydroxy-I,2-oxaborole, was coupled with cis-ethyl-iodo-acrylate to yield ethyI 2E, 4Z, 8E-9-phenyl-7-hydroxy-2, 4, 8-nonatrienoate, which is capable of undergoing an intramolecular Michael addition to form the dihydropyran. The geometry of the cis enolate and the conjugated double bonds of the coupled product are such that under basic conditions a Michael addition is feasible. Throughout the project, the reaction conditions for high yields of Suzuki product were determined. Dihydropyrans …

Cytotoxicity Of Cu(Ii) And Zn(Ii) 2,2′-Bipyridyl Complexes: Dependence Of Ic 50 On Recovery Time, Yi Shi, Bonnie B. Toms, Namrata Dixit, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

We measure the cytotoxicity of three metal complexes containing the 2,2′-bypyridine ligand, Cu(bpy)(NCS) ₂, 1, [Cu(bpy) ₂(H ₂O)](PF ₆) ₂, 2, and Zn(bpy) ₂(NCS) ₂, 3, toward neuroblastoma cells (SK-N-SH) and ovarian cancer cells (OVCAR-3) using two different cell assays. The cells were exposed to various concentrations of the compounds for 1 h and the percent inhibition of cell growth, I, measured for various times after exposure, i.e., as a function of the recovery time t. After developing the theory showing the relationship between I and t, the cytotoxicity data were analyzed to …

Cytotoxicity Of Cu(Ii) And Zn(Ii) 2,2′-Bipyridyl Complexes: Dependence Of Ic_50 On Recovery Time, Yi Shi, Bonnie B. Toms, Namrata Dixit, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

We measure the cytotoxicity of three metal complexes containing the 2,2′-bypyridine ligand, Cu(bpy)(NCS)2, 1, [Cu(bpy)2(H2O)](PF6)2, 2, and Zn(bpy)2(NCS)2, 3, toward neuroblastoma cells (SKN- SH) and ovarian cancer cells (OVCAR-3) using two different cell assays. The cells were exposed to various concentrations of the compounds for 1 h and the percent inhibition of cell growth, I, measured for various times after exposure, i.e., as a function of the recovery time t. After developing the theory showing the relationship between I and t, the cytotoxicity data were analyzed to reveal that the two copper complexes, 1 and 2, cause the cells to …

Structural Basis For Catalysis By The Mono- And Dimetalated Forms Of The Dape-Encoded N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase, Boguslaw P. Nocek, Danuta Gillner, Yao Fan, Richard C. Holz, Andzrej Joachimiak

Chemistry Faculty Research and Publications

Biosynthesis of lysine and meso-diaminopimelic acid in bacteria provides essential components for protein synthesis and construction of the bacterial peptidoglycan cell wall. The dapE operon enzymes synthesize both meso-diaminopimelic acid and lysine and, therefore, represent potential targets for novel antibacterials. The dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase functions in a late step of the pathway and converts N-succinyl-l,l-diaminopimelic acid to l,l-diaminopimelic acid and succinate. Deletion of the dapE gene is lethal to Helicobacter pylori and Mycobacterium smegmatis, indicating that DapE's are essential for cell growth and proliferation. Since there are no similar pathways in humans, inhibitors …

Identification Of Sea Turtle Leeches Using Dna Barcoding, Triet Minh Truong, Audrey E. Mcgowin Ph.D., Adrian M. Corbett Ph.D.

Chemistry Student Publications

Fibropapillomatosis (FP) is a panzootic plaguing all species of sea turtles with green turtles having the highest percentage of affliction. Although fibropapilloma-associated turtle herpes virus (FPTHV) has been identified as the causative agent of FP, the primary vector triggering this chronic tumor-forming disease is still unknown. Parasitic marine leeches (Ozobranchus spp.) could be a potential mechanical vector behind the emergence of this panzootic, although it is uncertain if it is species specific. Ozobranchus spp. are very small and difficult to distinguish anatomically, and until now, there have been few attempts to document them. DNA barcoding using mitochondrial cytochrome c oxidase …

Environmental Analysis Of Toxic Metals Produced By Cigarette Smoking, Catherine H. Swandby, Melissa C. Rhoten, Joseph E. Garcia

Theses & Honors Papers

Trace metal elements introduced into our environment from anthropogenic sources can become toxic at high levels contributing to a host of human and animal health problems. The purpose of this work is to initially characterize toxic metals present in cigarette tobacco and ash using Electrothermal Atomic Absorption Spectroscopy (ETAAS). The broader impact of this study is to assess the environmental effects of cigarette smoking around designated smoking areas on the Longwood University campus. Smokers may not be informed about the potential harm to the environment from "ashing" directly on the ground. If the toxic metals present in cigarette ash are …

An Entrepreneurial Approach To Librarianship, Flora Shrode, Jennifer Duncan, Wendy Holliday

Library Faculty & Staff Publications

Librarians from Utah State University explain recent efforts to encourage subject librarians to take a more holistic view of their roles. We are shifting from a traditional emphasis primarily on collection development and refocusing on natural connections between collections, instruction, liaison, and reference service. The poster provides background about Utah State University’s situation and explains our approach to analyzing local needs and culture to inform development of a new organizational structure. We describe our vision of subject librarianship, the process by which we assessed librarians’ ideas and goals for performing as subject librarians, and the actions we are taking to …

The Reaction Of A Water Soluble Platinum Compound With Methionine And Derivatives, Yueh Ying Liao

Masters Theses & Specialist Projects

Water soluble platinum complexes are a recent area of emphasis of cisplatin chemistry. The water soluble complexes could have a reduced toxicity compared with cisplatin. Oxaliplatin, which has an oxalate leaving group, has previously been shown to have less nephro-toxicity and higher water solubility than cisplatin. [Pt(en)(oxalate)] (en = ethylenediamine) has been prepared from Pt(en)Cl2 and silver oxalate. This complex has been reacted with methionine and N-acetylmethionine at different molar ratios. At high Pt: methionine ratios, chelates with the sulfur and nitrogen atoms of the methionine are dominant; at lower Pt: methionine ratios, a bis-methionine product is formed. The en …

Section Abstracts: Chemistry

Virginia Journal of Science

Abstracts of the Chemistry Section for the 88th Annual Meeting of the Virginia Academy of Science, May 20-21, 2010, James Madison University, Harrisonburg, VA.

Functionalization Of Aromatic Organic Molecules By Anhydrous Fluorides And By Reductive Elimination Of Iodine(Iii), Bijia Wang

Department of Chemistry: Dissertations, Theses, and Student Research

Solution phase reactivity of nucleophilic fluoride reagents is attenuated by ion-pairing interactions. ¹H-¹⁹F HOESY competition experiments permit generation of a fluoride ion affinity scale in the weak-binding regime. Direct DFT calculations of ion pair interaction energies as well as calculated cation electrostatic potential maps can be used to predict solution phase ion pairing tendencies for closely related ammonium cations. It was found by studying the decomposition of tetra-substituted ammonium cations by fluoride that: 1) rates of E2 decomposition is faster than the S_N2 pathway; 2) aryl substituents destabilize the cations; 3) steric strain tends to …