Chemistry Commons^™

Breaking The Spell: Developing A New Generation Of Porphyrins For Treating Cerebral Tumors, Ryan Harrison Gray

Honors Capstones

No abstract provided.

Developmental Expression Of Xenopus Myosin 1d And Identification Of A Myo1d Tail Homology That Overlaps Th1, Janine M. Leblanc-Straceski, Anna Sokac, William Bement, Pablo Sobrado, Laura Lemoine

Chemistry Faculty Research & Creative Works

Xenopus laevis myosin 1d (XlMyo1d) is a member of the myosin I class, subclass 4. Members of this class are single headed, bind calmodulin light chains and have lipid binding domains in their tails. The rat myo1d homologue has been implicated in endosome vesicle recycling in epithelial cells. Mutations in the Drosophila myosin 1d homologue cause situs inversus in the abdomen. The XlMyo1d cDNA has been cloned and the derived amino acid sequence is 80% identical to the rat and human homologues. Sequence comparison revealed a novel isoform-specific tail homology embedded in the Tail Homology 1 (TH1) domain characteristic of …

Synthesis Of Diruthenium Complexes As Connectable Molecular Components, George Ling

Renée Crown University Honors Thesis Projects - All

There have been great advances in electronics and technology within the last few years. The field of nanotechnology can further improve electronics in terms of efficiency, size and costs. There exist nanowires and nanotransistors that could accomplish this, however there exists no good method of connecting the two components together. Using the bottom-up approach and chemical synthesis, the goal is to synthesize molecular jumper cables and connectable molecular components (CMCs).

The template of the CMC will have two ruthenium (Ru) metal centers connected by a conjugated, organic bridge. Coordinated to the ruthenium metal centers will be different ligands that affect …

Design, Synthesis, And Film Formation Of Fluorine Containing Colloidal Dispersions, Anuradha Misra

Dissertations

Fluoropolymers (FPs) have been subject of interest for many years, however due to extreme synthetic and processing conditions their applications have been limited. This dissertation focuses on design and synthesis of fluorine containing colloidal dispersions to advance limited knowledge and to gain further understanding of fluorine containing colloidal dispersions. Fluoroacrylates and fluoro methacrylates consisting of varying chain length of perfluoroalkyl side chain were copolymerized with methylmethacrylate (MMA) and n-butylacrylate (n-BA) under aqueous environment utilizing phospholipids (PLs) as dispersing agent. Morphologies of colloids, coalescence, and film formation processes after water evaporation was investigated using various microscopic probes such as transmission electron …

Influence Of Functional Components On The Film Formation Of Colloidal Dispersions, Kevin Lee Rhudy

Dissertations

A number of colloidal dispersions were synthesized to advance knowledge and gain understanding regarding interactions between individual components and for elucidation of complex processes governing their film formation. These studies show that for methyl methacrylate/n-butyl acrylate (MMA/nBA) colloidal dispersions, the presence of functional components significantly affects film formation. The incorporation of polyvinyl alcohol (PVOH) into pMMA/nBA colloidal dispersions creates competing environments between the copolymer particle surfaces, aqueous phases, and dispersing agents which results in migration with self-induced stratification occuring during coalescence. pMMA/nBA/PVOH films stratify to form sodium dodecyl sulfate (SDS) rich film-air (F-A) interfaces, and the -SO3" moieties exhibit preferential …

The Synthesis And Characterization Of Novel Microporous Hybrid Organic/Inorganic Materials, Kelly Whitenack

Renée Crown University Honors Thesis Projects - All

Inorganic chemistry is essential to the formulation and improvement of modern materials such as catalysts, semiconductors, optical devices, super conductors, and advanced ceramic materials.¹ New areas of inorganic chemistry are constantly being explored and new and often unusual inorganic compounds are constantly being synthesized and identified.¹ Recently the field of inorganic chemistry has witnessed the synthesis and characterization of microporous metal organic framework compounds (MOFs). Microporous organic/inorganic materials have a wide range of physical properties as well as applications. The physical properties and applications drive the investigation into the synthesis and discovery of new and useful hybrid MOF …

Towards Novel Alkaline Earth Metal Pyrazolates: Opportunities In Materials Chemistry, Michael G. Bagnall

Renée Crown University Honors Thesis Projects - All

Until recent years, the coordination chemistry of the alkaline earth metals remained relatively unexplored. Owing to the development of new synthetic methods and improved techniques for the exclusion of air and moisture, great progress has been made into our understanding of the alkaline earth metals and their compounds. These compounds are useful in a wide variety of applications, including as polymerization initiators, precursors for chemical vapor deposition (CVD) and in metal-organic frameworks (MOFs) for gas separation and storage. Current work in alkaline earth metal chemistry focuses on designing and tailoring ligand systems to expand their potential applications in materials chemistry. …

Rational Design And Synthesis Of Multifunctional Nanostructures For Biological And Medicinal Applications, Amy N. Otuonye

Renée Crown University Honors Thesis Projects - All

Mobile Composite Material (MCM-41) was modified by the addition of various functional groups, which increase the materials’ efficiency for an assortment of applications. Mesoporous materials have demonstrated to be capable of adsorbing and releasing of model drug molecules, rhodamine 6G and ibuprofen. Mesoporous silica materials functionalized with mercaptopropyltrimethoxysilane (MPTS), vinyltrimethoxysilane (VTS), aminopropyltrimethoxysilane (APTS), and N-(2-animoethyl)-3-aminopropyltriethoxysilane (AAPTS) were used to test the adsorption and release of rhodamine 6G (R6G) and ibuprofen. The vinyl and mercaptopropyl groups adsorbed and released more rhodamine 6G than the primary and secondary amine groups. The adsorption and release of ibuprofen was the opposite of the R6G …

The Synthesis And Systematic Evaluation Of Modified Polymeric Foams And Electrically Conductive Polyimide/Carbon/Metal Films, John Macharia Kinyanjui

UNLV Theses, Dissertations, Professional Papers, and Capstones

Thermally processed PU foams are examined as a function of processing temperatures (25, 45, 65, and 85°C) at the side, middle, and center of a simple cylindrical mold. The PU foams show both chemical and morphological differences as a function of the processing temperature and radial position within the mold. Thermal degradation of uretoneimine structures, the emergence of carbodiimide structures, and extent of reaction of isocyanate groups are measured using photoacoustic FTIR spectroscopy. Chemical gradients and morphology differences between the side, middle, and center of the molded foam are observed for all processing temperatures. The data indicate that thermal activation …

Completing Chemistry Taks Objective 4(9d): The Effect Of Flash Animation, Judith B. Dano

Theses and Dissertations - UTB/UTPA

This study examines the effect of flash animation on learning effectiveness. The main goal of the study was to verify if using flash animation on learning chemistry concepts particularly Chemistry TAKS Objective 4 (9D) will have an impact on students learning achievement. The subjects in this study were 10th grade students from PSJA Memorial High School. Two class sections were randomly assigned as the treatment group each with 20 subjects (n=40) and another two class sections were assigned as the control group (n=40). The treatment group was exposed to flash animation while the control group had the traditional lecture type …

Electrospinning Polystyrene Reinforced With Multi-Walled Carbon Nanotubes: Parameters For Obtaining Nanofibers With Enhanced Thermal Properties, Ana Veronica Rodriguez Ybarra

Theses and Dissertations - UTB/UTPA

Various concentrations of multi-walled carbon nanotubes (MWCNTs) were dispersed in a polystyrene matrix in order to determine the optimal MWCNT concentration that would enhance the thermal properties of the composite. The MWCNTs were dispersed in the polystyrene matrix by high energy sonication and then electrospun. The microstructural characterization such as fiber diameter, fiber orientation, fiber morphology, porosity, cross-section shape, and surface roughness of the nanofibers electrospun from these composites were made by scanning electron microscopy and transmission electron microscopy. Spectroscopic characterization for these nanofibers was conducted using Fourier Transform infrared spectroscopy and Raman spectroscopy was utilized to establish a nanotube/matrix …

Methyl Septanoside Hydrolysis As A Measure Of Carbohydrate Ring Flexibility: Substrate Synthesis And Kinetics Analysis, Shawn Michael Miller

Honors Scholar Theses

A number of seven-membered ring systems have been found to have promising enzyme inhibiting properties. The common explanation for their efficacy is the apparent improved flexibility that the ring-system has over smaller rings. In an attempt to probe the validity of this hypothesis, unnatural seven-membered ring carbohydrates have been generated and subjected to kinetics analysis using hydrolysis. In particular, methyl α- and β-D-glycero-D-guloseptanoside were subjected to acid-catalyzed hydrolysis and monitored via HNMR experiments. The rate constants of the reactions were determined and compared to the hydrolysis rate constants of comparable pyranose carbohydrates and found to be significantly faster, indicating an …

Functional Characterization And Assembly Studies Of Carboxysomes In Halothiobacillus Neapolitanus, Zhicheng Dou

Dissertations

Functional characterization and assembly studies of carboxysomes in Halothiobacillus neapolitanus were pursued in order to understand the roles of carboxysomes in the carbon metabolism in H. neapolitanus and the assembly of carboxysomes in vitro and in vivo. Previously, a low abundance H. neapolitanus carboxysomal protein, CsoSCA was identified as a novel carboxysomal shell-bound carbonic anhydrase. The enzyme is thought to dehydrate the cytosolic bicarbonate to CO2, the substrate of the RuBisCO packaged within the carboxysome [14, 21]. In this study, the carboxysomal shell was identified as a diffusion barrier for CO2 and O2 molecules. The shell-bound CsoSCA protein facilitates the …

Magnetic And Dielectric Properties Of Sulfonated (S) Poly[(Styrene)-(Ethylene-Co-Butylene)-(Styrene)] (Sebs) Block Copolymer/Magnetic Metal Oxide Nanocomposites Synthesized Via An In-Situ Precipitation Method, Sateesh Kumar Peddini

Dissertations

Block copolymer/magnetic metal oxide nanocomposites were synthesized by growing metal oxide nanoparticles (cobalt ferrite, CoFe204 and iron oxide, a-Fe203) in sulfonated (s) poly (styrene) (PS) block domains of sulfonated poly [(styrene)-(ethyleneco- butylene)-(styrene)] (SEBS) BCP preformed films via an in-situ precipitation method by dissolving the salts of respective metal chloride (s) in a suitable solvent that selectively swells the sPS regions. Inorganic uptake was determined using thermogravimetric analysis (TGA), and it was observed that none of the samples incorporated more than 5 wt % of the inorganic component. Dynamical mechanical analysis was used to observe the changes in the glass transition …

Molecular Interactions Involved In The Biogenesis Of Bacterial Microcompartments, Balaraj Balaram Menon

Dissertations

This study was undertaken with the goal of gaining better insights into the assembly pathway of carboxysomes and related polyhedra. Aside from their similarity in size and shape, all known microcompartments package enzymes that mediate key reactions of metabolic pathways [1]. It remains unclear whether the sequestered enzymes participate in microcompartment assembly and/or contribute to the overall shape of the polyhedra. Genetic studies in Salmonella enterica have suggested that the shells of organelles involved in propanediol utilization assemble in the absence of encapsulated enzymes [2]. In this study, in vivo yeast two-hybrid screens, involving components of the ethanolamine utilization (Eut) …

Investigation Into Select Isoquinolines As A Putative Causal Agent Of Ethanol Addiction In Mammals, Jacob Christopher Strawbridge

Dissertations

Alcohol is the most abused drug in America today. The neurological root of the problem is still a much debated subject and many differing views exist on the nature of alcoholism, be it a social dysfunction or a neurochemical imbalance. Some researchers have proposed that a skewed metabolism of dopamine that results in the formation of tetrahydroisoquinoline (THIQ) alkaloids plays a major role in the neurochemical acquisition and maintenance of alcohol addiction. In an effort to better understand the relationship of THIQ's to alcohol addiction, a series of experiments have been conducted. The chiral separation via high pressure liquid chromatography …

Raft Synthesis Of Water-Soluble, Stimuli-Responsive (Co)Polymers And Post-Polymerization End Group Modification Via The Thiol-Ene Reaction, Bing Yu

Dissertations

A series of water-soluble, stimuli-responsive (co)polymers was synthesized via the reversible addition-fragmentation chain transfer (RAFT) polymerization. The end group of a RAFT polymer, poly(jV-isopropylacrylamide), was modified to ene or yne function via thiol-ene click chemistry. The ene or yne end group subsequently underwent thiol-ene or thiol-yne addition affording mono- or di-functional end group. First, three methacrylic monomers containing 2 or 3 pendent tertiary amine functional groups, l,3-bis(dimethylamino)propan-2-yl methacrylate (Ml), l-(bis(3-(dimethylamino)propyl)amino)propan-2-yl methacrylate (M2), and 2-((2-(2-(dimethylamino)ethoxy)ethyl)methylamino)ethyl acrylate (M3), were synthesized via an acylation reaction between methacryloyl chloride and the corresponding aminoalcohol. All of these three monomers were successfully homopolymerized under RAFT conditions …

Water Quality Changes In A Constructed Wetland At The Springs Preserve In Las Vegas, Nevada, Aaron Mathis Miller

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Springs Preserve near downtown Las Vegas, Nevada contains a seven-acre constructed wetland. Springs Preserve managers are planning to use water from the constructed wetland to irrigate creeks immediately north of the wetland. These creeks will be used by a variety ofaquatic wildlife, including endangered amphibians sensitive to harmful metalloids, such as selenium, lead, and arsenic.

In an attempt to answer toxicological questions about contaminant concentrations in the constructed wetland, three metals and metalloids (selenium, arsenic, and lead), two nutrients (nitrogen and phosphorus), and the major ionic species were analyzed at four sampling locations for aqueous concentrations, in two separate …

Evaluation Of Low-Temperature Fluoride Routes To Synthesize Actinide Nitrides And Oxide Solid Solutions, Gunanda Waduge Chinthaka Silva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Actinide mononitrides have been considered as a possible nuclear fuel for the Generation-IV nuclear reactor systems. In the process of evaluating these actinide mononitrides as nuclear fuel, it is important to study different chemical and physical characteristics of these compounds. Synthesis of the materials is thus important. Carbothermic reduction is one of the techniques that have been used to synthesize actinide mononitrides. In this method, a mixture of actinide oxide such as UO ₂ and excess carbon is heat treated at temperatures greater than 1700 °C under a nitrogen atmosphere. The technique is however not promising in synthesizing the actinide …

Synthetic Studies Of Laulimalide Analogues, Ian Addison Mcalexander

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chapter 1 provides some background information on the disease area of cancer and current modes of treatment. Chemotherapy treatment is discussed with a focus on the major cellular targets for these drugs: DNA and microtubules. For each target, classes of active compounds are described along with their mode of action. The microtubule stabilizing agent laulimalide is introduced and a case is made for analogue synthesis.

Chapter 2 describes our first generation efforts toward synthesis of des-methyl laulimalide. The target compound is divided into a northern and southern fragment with the synthesis of each fragment described. The preparation of landmark intermediates …

Sonication Assisted Synthesis Of Oligomannosides, Christabel Tomla Tanifum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oligomannosides prevalently exist as cell surface antigens. They play important roles in diseases such as viral infection and cancer, and they have been shown to be useful as candidates for vaccines. HIV, one of the most devastating modern diseases, has a high content of mannose sugars on its envelope glycoprotein gp120. Oligomannosides of the HIV virus, also called Man9, which are found on the glycoprotein gp120, have been shown to play a protective role for the HIV virus, shielding highly conserved protein domains of gp120 from proteolytic attacks. Thus gp120 plays an important role in HIV infection of cells, being …

Identifying Biomarkers For Resistance To Novel Cisplatin Analogues In Human Lung, Breast And Prostate Cancers, Becky Michelle Hess

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cisplatin is a common therapeutic agent used in cancer treatment. Unfortunately, resistance to cisplatin in addition to severe side effects limits its use in cancer treatment. Two novel cisplatin analogues, 4DB and 4TB were shown to have varying cytotoxicity in lung, breast and prostate cancer cells. The hypothesis for this study states that the differences in 4DB and 4TB cytotoxicity among different tissue types is due to the type and efficiency of DNA repair mechanisms involved in response to these drugs.

To test the hypothesis, proteins involved in the rate limiting step of nucleotide excision repair (NER) and mismatch repair …

Specific And Non-Specific Binding Of Proteins And Nucleic Acids On Chemically Modified Reticulated Vitreous Carbon Electrodes, Hemangi Shedge

All Theses

Proteins and nucleic acids play major roles in many important biological processes. Specific and rapid detection of these biomolecules is important for early and precise diagnosis of various genetic diseases and other medical conditions. However, accurate and inexpensive detection of proteins and nucleic acids has always been a challenge. One of the obstacles is their non-specific adsorption on the sensor surface which leads to the conformational changes in the proteins, sometimes causing their denaturation. The non-specific adsorption on the surface also leads to sensor fouling which induces changes in the availability of active sensor surface for detection of analytes and …

Synthesis Of Ionic Liquid Monomers Using Fluorinated Sulfonyl Imide Anions And The 1,3-Dialkylimidazolium Cation, Thomas Hickman

All Dissertations

With their unique material and solvent properties, ionic liquids have seen an amazing, exponential increase in interest. After a brief introduction of select areas of interest for these compounds, this thesis mainly focuses on the development of novel polyfunctional ionic liquids and polymeric ionic liquids.
One of the preferred anions for ionic liquids is the bis((trifluoromethyl)sulfonyl) imide anion, first introduced by our group in 1982. It shows excellent thermal stability and the desired resonance delocalization of a negative charge for ionic liquids. A series of monofunctional, difunctional, and multi-functional bis(perfluoroalkylsufonyl)imides, along with 1,3-dialkylimidazolium cations were prepared by direct methylation of …

Organocuprate Mediated Syntheses Of O, And N-Heterocycles, Fenghai Guo

All Dissertations

ABSTRACT
The δ-lactone moiety comprises structural subunits in a number of natural products. Highly substituted δ-lactones are important both in synthetic applications and also as naturally occurring compounds. We have reported a one-pot procedure for the synthesis of trans-4,5-disubstituted tetrahydropran-2-ones from 3-hydroxy-3,6-dihydropyran-2-one involving sequential cuprate mediated allylic substitution and 1,4-conjugate addition reactions. We have now examined the same protocol for synthesis of 4,5,6-trisubstituted δ-lactones.
The rich functionalities(i.e. the epoxide, olefin and ester functional groups) in ,δ-epoxy-α,β-enoates provide opportunities for SN2-epoxide opening, allylic substitution, and 1,4-conjugated addtion. The opening of the epoxide with AcCl, AcBr, and benzoyl chloride afforded the -acetoxy--halo-,-enoates …

Fundamental Aspects Of Small Molecules And Macromolecules On Poly(Ethylene Terephthalate) Capillary-Channeled Polymer Fibers, Christine Straut

All Dissertations

Stationary phases and adsorbents are continually being developed to enhance separations in high performance liquid chromatography (HPLC). Polymeric stationary phases have gained popularity due to their ability to be employed over a large pH range and because they are more chemically robust when compared to silica based phases. Capillary-channeled polymer (C-CP) fibers are an alternative to traditional porous packed bed beads. These fibers have a unique geometry with increased the surface area/volume ratios when compared to cylindrical fibers. Very unique characteristics are realized in the use of the C-CP fibers, including drastically reduced backpressures and selection of solute-surface interaction through …

Analyzing The Binding Of Co(Ii)-Specific Inhibitors To The Methionyl Aminopeptidases From Escherichia Coli And Pyrococcus Furiosus, Sanghamitra Mitra, George Sheppard, Jieyi Wang, Brian Bennett, Richard C. Holz

Chemistry Faculty Research and Publications

Methionine aminopeptidases (MetAPs) represent a unique class of protease that is capable of the hydrolytic removal of an N-terminal methionine residue from nascent polypeptide chains. MetAPs are physiologically important enzymes; hence, there is considerable interest in developing inhibitors that can be used as antiangiogenic and antimicrobial agents. A detailed kinetic and spectroscopic study has been performed to probe the binding of a triazole-based inhibitor and a bestatin-based inhibitor to both Mn(II)- and Co(II)-loaded type-I (Escherichia coli) and type-II (Pyrococcus furiosus) MetAPs. Both inhibitors were found to be moderate competitive inhibitors. The triazole-type inhibitor was found to …

Detecting Organic Molecules On The Surface Of Inorganic Dust Particles Using Aerosol Mass Spectrometry, Sileola B. Akinsiku

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detection of organic molecules present on the surface of dust particles is important in homeland security, agriculture, and several other applications. The research presented reports the ability of the aerosol mass spectrometer (AMS) to detect molecules on the surface of dust particles without detecting the particle core.

Experiments were carried out to detect semi-volatile organic compounds adsorbed onto the surface of particulates without interference from the dust particle core. Methyl salicylate, oleic acid, and organophosphorus pesticides such as Malathion were detected on the surface of particles representative of dust-type materials. Zeolite powders were used as aerosol support, representative of a …

Carbohydrate Derivatives In Antibiotics Research, Yi Liang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this study, we investigated the potential applications of carbohydrates in the development of new antibiotics. To tackle the problem of multidrug-resistant variants of M. tuberculosis (MDR-TB), we investigated the biosynthesis pathways of trehalose, which has contributed to significant drug resistance. Some new methods were developed for the synthesis of potential inhibitors (6-azido-trehalose and 6,6'-diazido-trehalose) that have been designed to imitate the intermediate molecule (trehalose 6-phosphate, TPP) of OtsA-OtsB pathway. At the same time, some new antibacterial agents based on trehalose have been synthesized. Members of the 1,2,3-triazole family have shown interesting biological properties. Steroid derivatives have been developed in …

A Comparative Study Of The Structural Features And Kinetic Properties Of The Mofe And Vfe Proteins From Azotobacter Vinelandii, Miguel Alejandro Pabon Sanclemente

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biological nitrogen fixation is accomplished in the bacterium Azotobacter vinelandii by means of three metalloenzymes: The molybdenum, vanadium, and iron-only nitrogenase. The knowledge regarding biological nitrogen fixation has come from studies on the Mo-dependent reaction. However, the V- and Fe-only-dependent reduction of nitrogen remains largely unknown.

By using homology modeling techniques, the protein folds that contain the metal cluster active sites for the V- and Fe-only nitrogenases were constructed. The models uncovered similarities and differences existing among the nitrogenases regarding the identity of the amino acid residues lining pivotal structural features for the correct functioning of the proteins. These differences, …