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Toward Development Of A Paper-Based Microanalytical Device For Heavy Metal Ion Detection By Enzyme Inhibition, Adjoa Otubea Adams

Graduate Theses/Dissertations

In recent years, paper-based microanalytical devices have attracted great attention in broad application areas including the colorimetric detection of heavy metal ions. The simplicity, portability, and low cost of the devices offer unique advantages over conventional instrumental analysis. This project utilizes the inhibition of an enzyme-catalyzed reaction by metal ions to develop a paper-based analytical device for the detection of heavy metal contaminants such as mercury. I selected alkaline phosphatase for this study. This enzyme possesses Mg and Zn ions in its active site. Therefore, the competitive displacement of these metal ions and/or denaturation of the enzyme by heavy metal …

In Silico Investigation For The Conversion Of Methyl Oleate To Gasoline, Arkanil Roy

Graduate Theses/Dissertations

Petroleum products are found in all walks of life. From the plastic casing on a cell phone to the gasoline that runs most vehicles, a lot is derived from petroleum. Ubiquitous use of petroleum has adversely affected the environment. Toxic substances such as SOx and NOx are released into the atmosphere during the processing and usage of petroleum products, which contributes to global warming. Inevitable oil spills cause devastating effects to marine ecosystems. The rate of regeneration of petroleum is much slower than the rate of usage that would lead to it being exhausted in the recent future. Hence, a …

Investigating Chitosan Modified With Triethylammonium Butanamide And Triethylphosphonium Butanamide As Non-Viral Gene Delivery Vectors By Examining Cytotoxicity And Transfection Efficiency, Deborah C. Ehie

Graduate Theses/Dissertations

Gene therapy is a very challenging field, especially with new emerging genetic disorders. Chitosan (CS), due to chitosan’s flexibility, biocompatibility, and biodegradability, has been of interest in the world of gene therapy especially as researchers are gravitating towards non-viral vectors due to the problems caused by viral vectors. Nevertheless, there are still issues regarding solubility, cellular uptake of cargos being transported in vitro or in vivo, increased cytotoxicity levels, as well as many other things that prevent chitosan from being an efficient gene delivery agent. Here I present five derivatives of chitosan, which were all modified with either triethylphosphonium …

Nanoceria Distribution And Effects Are Mouse-Strain Dependent, Robert A. Yokel, Michael T. Tseng, D. Allan Butterfield, Matthew L. Hancock, Eric A. Grulke, Jason M. Unrine, Arnold J. Stromberg, Alan K. Dozier, Uschi M. Graham

Pharmaceutical Sciences Faculty Publications

Prior studies showed nanoparticle clearance was different in C57BL/6 versus BALB/c mice, strains prone to Th1 and Th2 immune responses, respectively. Objective: Assess nanoceria (cerium oxide, CeO₂ nanoparticle) uptake time course and organ distribution, cellular and oxidative stress, and bioprocessing as a function of mouse strain. Methods: C57BL/6 and BALB/c female mice were i.p. injected with 10 mg/kg nanoceria or vehicle and terminated 0.5 to 24 h later. Organs were collected for cerium analysis; light and electron microscopy with elemental mapping; and protein carbonyl, IL-1β, and caspase-1 determination. Results: Peripheral organ cerium significantly increased, generally more …

Determining The Relative Activities Of Wild-Type Mycobacterium Tuberculosis Indole-3-Glycerol Phosphate Synthase And Mutants E57a And E219a With An Investigation Into The Relationship Between Wild-Type Mycobacterium Tuberculosis Igps Activity And Ph, Thomas Emmanuel Candela

Theses, Dissertations and Culminating Projects

The relationship between wild-type protein indole-3-glycerol phosphate synthase (IGPS) activity and pH was investigated through the formation of pH activity profiles, and the relative catalytic activities of wild-type Mycobacterium tuberculosis and mutants E57A and E219A were also deduced in this work. The activity of each enzyme variant was determined by reacting native substrate 1-(o-carboxyphenylamino)-1-deoxyribulose-5-phosphate with enzyme buffered at pH 7.5 in a cuvette and using a fluorometer to detect the increase in fluorescent signal produced by the formation of fluorescent product indole-3 glycerol phosphate. Work with wild-type IGPS showed the enzyme to have a kcat of 1.26 ± 1.75 (s …

Characterizing Functions Of Two Regulatory Proteins In The Parasitic Nematode Brugia Malayi And Their Potential As Drug Targets In Treating Lymphatic Filariasis, Brittany Amber Hart

Theses, Dissertations and Culminating Projects

Lymphatic filariasis (LF) is a debilitating disease caused by parasitic nematodes that affect millions of people in largely tropical environments. While drugs are available for treating LF, they suffer from a lack of efficacy against adult parasites, toxicity, and emergence of resistance. Here, we describe two novel potential drug targets within the filarial parasite, Brugia malayi (B. malayi). These two proteins, bm9350, a predictive MAPK stress response protein, and bm2032, a potential histone modifying enzyme, have little or no annotation or experimental evidence of function. Using predictive analysis and tools, we examined potential functions of these proteins and their potential …

Studies Toward The Synthesis Of A Novel Diamine Scaffold, Joseph Edward Quinlan Iii

Theses, Dissertations and Culminating Projects

The orexin system in humans contains receptors Orexin 1 (OX1) and Orexin 2 (OX2). These receptors are involved in numerous physiological processes including wake/sleep cycling, energy homeostasis, and motivation/reward. In scientific literature, it is known that antagonism of these receptors exhibits therapeutic effects in the realm of cocaine and alcohol addiction, as well as sleep disorders. On the market today exist drugs for treatment of sleep disorders through orexin receptor antagonization. Here we report a synthesis toward novel conformationally rigid antagonists of the orexin receptor system that may provide improved affinity and/or selectivity compared to known compounds. We report the …

Strategies For Enhancing Chromatographic Efficiencies In Chiral And Achiral Supercritical And Liquid Chromatography, Daipayan Roy

Chemistry & Biochemistry Dissertations - Archive

The fundamental aim of chromatography has been to achieve baseline separation between the components of a mixture in the shortest possible time. Recently there has been a shift in the chromatographic focus of enantiomeric separations, with an emphasis on increasing the efficiency of columns. Superficially porous particles (SPP) introduced about a decade ago lead to a surge in efficiency as compared to the traditionally used fully porous particles (FPP). Recently chiral selectors bonded to superficially porous particles have been commercialized. This work reports new methods for enantioseparation using chiral selectors like macrocyclic glycopeptides, modified cyclodextrins and cyclofructans bonded to SPPs. …

Solving The Conundrum: Widespread Proteins Annotated For Urea Metabolism In Bacteria Are Carboxyguanidine Deiminases Mediating Nitrogen Assimilation From Guanidine, Nicholas O. Schneider, Lambros J. Tassoulas, Danyun Zeng, Amanda J. Laseke, Nicholas J. Reiter, Lawrence P. Wackett, Martin St. Maurice

Chemistry Faculty Research and Publications

Free guanidine is increasingly recognized as a relevant molecule in biological systems. Recently, it was reported that urea carboxylase acts preferentially on guanidine, and consequently, it was considered to participate directly in guanidine biodegradation. Urea carboxylase combines with allophanate hydrolase to comprise the activity of urea amidolyase, an enzyme predominantly found in bacteria and fungi that catalyzes the carboxylation and subsequent hydrolysis of urea to ammonia and carbon dioxide. Here, we demonstrate that urea carboxylase and allophanate hydrolase from Pseudomonas syringae are insufficient to catalyze the decomposition of guanidine. Rather, guanidine is decomposed to ammonia through the combined activities of …

Innovative Approaches In The Discovery Of Aquatic Mycobacteriophages, Janis H. Doss

Biomedical Sciences Theses & Dissertations

Bacteriophages (phages), viruses that infect bacteria, have many applications in medicine, agriculture, molecular biology, and other fields. As antibiotic resistance becomes an increasing problem, interest in phages has grown. The traditional techniques of phage discovery are successful for some phages, but others require modified procedures to achieve detectable host infection.

Mycobacterium is a diverse bacterial genus characterized by a unique cell wall containing mycolic acids, which aids in survival and pathogenesis. The aims of the present research were to isolate mycobacteriophages, use bioinformatics techniques to analyze mycobacterial prophages, and combine genetic analysis with multi-well plate host range studies to identify …

Water Cluster Motifs In Structurally Similar N-(2-Aminoethyl)-1-Methylimidazole-2-Carboxamide Metal Complexes: Synthesis, Characterization, Thermal And Electrical Properties., Nina Saraei

Electronic Theses and Dissertations

Water is a remarkable molecule and in all of its forms exhibits an amazing collection of properties and functions. Besides its crucial role in life and many technological processes, water displays some unusual and anomalous properties at various interfaces and under different conditions. Although the role of hydrogen-bonding interactions and their fluctuations are well known to determine the properties of water, the main obstacle exists in the complexity of correctly describing the interactions between water molecules. The key to understanding the behavior of water is to collect precise structural data of various H-bonded water networks in diverse environments. In this …

The Legacy Of Mining In Southwest Missouri: Past And Present Conditions Of The Tri-State Mining District, Anastasia M C Mcclanahan

Graduate Theses/Dissertations

The historic Tri-State Mining District (TSMD) of southwestern Missouri, southeastern Kansas, and northeastern Oklahoma has a history of lead and zinc mining that extended over a hundred years. During the district’s peak production period, the TSMD was one of the world’s largest producers of lead and zinc. The mining activities in the TSMD produced economic growth that supported the local communities and were essential to the victory of the Allied Forces during World War I and World War II. Beginning in the 1920s, the mining activities in the district slowly began to cease due to depletion of metal ores and …

Assessing The Robustness And Versatility Of Nanojars For Anion Binding, Mia Lily Ann Jawor

Masters Theses

Supramolecular chemistry is a field in chemistry that focuses on intermolecular bonds in a “host-guest complex” or supramolecular assemblies. Nanojars are supramolecular assemblies of the formula [anion⊂{Cu(μ-OH)(μ-pz)}_n] (n = 27‒33) which incarcerate kosmotropic anions, such as carbonate (CO₃^2‒), sulfate (SO₄^2‒) and hydrogen phosphate (HPO₄^2‒). Nanojars consist of three [Cu(μ-OH)(μ-pz)]_x (x = 6‒14, except 11) rings that are assembled similarly to Matryoshka dolls, where the top and bottom rings act as guests for the central ring. The larger central ring is bound to the two smaller rings by multiple …

Embedded Gold Nanoparticles For Metal Enhanced Photoluminescence, Hasna Alali

Dissertations

Noble metal nanoparticles (MNPs) have attracted great attention in electronics, solar cells and catalysis. Their unique optical properties and biocompatibility makes them useful in biological applications like imaging, drug delivery, therapy and diagnostic. At the surface of MNPs the collective oscillation of free electrons resonates with a particular wavelength of incident light, generating the Localized Surface Plasmons Resonance (LSPR). LSPR results in absorption and scattering of incident light. Scattering results in reflecting photons and absorption leads to enhanced photoluminescence and quenching of fluorophores, if the fluorophore is in the vicinity of MNPs.

Most of the studies in this regard have …

Structural Characterization Of Organic Matter In Oil Shales Using Multiple Nuclear Magnetic Resonance Spectroscopic Techniques, Wenying Chu

Chemistry & Biochemistry Theses & Dissertations

Oil shale is a promising source of hydrocarbon fuel that is distributed throughout the world. The petroleum generating potential of oil shale is related to the molecular structure of the organic matter in source rock. The major fraction of organic matter of oil shale is termed kerogen, and due to its insolubility in organic solvents, ¹³C solid-state nuclear magnetic resonance (NMR) spectroscopy is one of the best ways to directly measure the insoluble organic matter without changing its chemical structures. This dissertation investigated oil shale samples using advanced solid-state ¹³C NMR spectroscopy techniques and high resolution magic angle …

Application Of Carbon Nanoparticles As Dna Detection Probe And Fluorescent Ink, Luckio Frank Owuocha

Graduate Theses/Dissertations

There is a significant interest in developing a sensitive, selective, efficient, and inexpensive method for rapid molecular diagnostic tests. This research aims to develop an inexpensive nucleic acid detection method by using DNA-conjugated carbon nanoparticles that exhibit fluorescence in the visible region. Carbon nanoparticles of this class can be detected without specialized equipment and have great promise toward the development of analytical methods that can be used in resource-limited environments with a lack of access to proper diagnostic and healthcare. We employed EDC-NHS (two-step) and EDC (one-step) coupling techniques to prepare DNA-conjugated carbon nanoparticles. The dot blotting method was adapted …

Synthesis, Characterization, And Biological Studies Of Novel Organoantimony(V) Cyanoximates, Kevin Anthony Pinks

Graduate Theses/Dissertations

The requirement of new antimicrobial treatments has become an urgent field recently. Multi-drug resistant (MDR) bacteria are now resistant to common antibiotics. To antagonize such bacteria 8 novel organoantimony(V) cyanoximates were synthesized to be characterized and submitted for biological activity studies. Eight organoantimony(V) cyanoximates were characterized by elemental analysis, thermal analysis, IR-, ¹³C{¹H} NMR, some with UV-visible spectroscopy, and single crystal X-ray analysis. Antimicrobial Disk studies indicated Sb(Ph)₄(ACO) and Sb(Ph)₄(ECO) had significant antimicrobial effect against all three strains: two gram-negative a) Escherichia coli strain S17 and b) Pseudomonas aeruginosa strain PAO1, alongside a …

Characterization Of An Acid Rock Drainage Microbiome And Transcriptome At The Ely Copper Mine Superfund Site, Lesley Ann Giddings, George Chlipala, Kevin Kunstman, Stefan Green, Katherine Morillo, Kieran Bhave, Holly Peterson, Heather Driscoll, Mark Maienschein-Cline

Chemistry: Faculty Publications

The microbial oxidation of metal sulfides plays a major role in the formation of acid rock drainage (ARD). We aimed to broadly characterize the ARD at Ely Brook, which drains the Ely Copper Mine Superfund site in Vermont, USA, using metagenomics and metatranscriptomics to assess the metabolic potential and seasonal ecological roles of microorganisms in water and sediment. Using Centrifuge against the NCBI “nt” database, ~25% of reads in sediment and water samples were classified as acid-tolerant Proteobacteria (61 ± 4%) belonging to the genera Pseudomonas (2.6-3.3%), Bradyrhizobium (1.7-4.1%), and Streptomyces (2.9-5.0%). Numerous genes (12%) were differentially expressed between seasons …

Unbinding Of Testosterone From The Androgen Receptor And Two Bf-3 Site Mutants, Muniruzzaman Chowdhury

Theses and Dissertations

The androgen receptor (AR) can be activated by molecules binding in the steroid binding pocket. It can also be regulated allosterically by cofactors binding to the AF-2 surface site as well as by exogenous small molecules binding to the BF-3 surface site. Recent data indicated that mutations in the BF-3 site changed the amount of the endogenous steroid needed to activate the receptor, indicating that mutations of BF-3 can cause an allosteric effect. Molecular dynamics and steered molecular dynamics simulations were used to study the allosteric effect of the mutations on AR structure and the unbinding pathways of testosterone (TES) …

Nonwovens Of Ceramic Decorated Cellulose Based Fine Fibers For Leaded Water Purification, Alejandro J. Castillo

Theses and Dissertations

Fine fibers of cellulose acetate were Forcespun and used to make nonwoven mats of cellulose. Nonwovens were activated using a solution combustion synthesis which deposited iron nitride onto fibers. Cellulose and cellulose composite mats were tested as adsorbents for lead ion in water. Cellulose showed slightly higher adsorption capacities (mg/g) up to 1300 mg/g lead loading. Adsorption data were further analyzed using several isotherms, of which the Dubinin-Raduskevich gave the best fits.

Synthesis And Biological Activities Of Imidazolium Acridines And Their Silver Complexes, H S Sharhan Olla

Student Works (2020-2029)

In the present study, a series of acridine-based imidazolium ligands were synthesized by the Menshutkin reaction and used for the preparation of the silver complexes. The structures were established using NMR and IR spectroscopy as well as high-resolution mass spectrometry. The purity of the ligands was confirmed by CHN elemental analysis, while energy-dispersive X-ray spectroscopy (EDX) was applied for the silver complexes. In view of the luminescent behaviour of acridine, UV-Vis and fluorescence spectra were recorded for ligands and complexes. However, low water solubility constrains potential application as analytical probe. Preliminary in vitro cytotoxicity screenings were performed using an MTT …

Effect Of Electron Demand On Sensing Behavior Of Carbazolopyridinophanes, Grace Abban

Theses and Dissertations

Hydrazine (HZ), monomethylhydrazine (MMH), and 1,1-dimethylhydrazine (UDMH) are widely used as high energy rocket propellants in bipropellant rocket engines. However, hydrazine and its derivatives are highly flammable and carcinogenic. Currently, hydrazine sensors used for detection are irreversible which makes them costly. Two proposed carbazolopyridinophanes containing intramolecular hydrogen bonds were synthesized to detect hydrazine as real-time reversible sensors. However, their thresholds for detection (100 and 25 ppb for CPand 22OMeCPrespectively) were above the regulatory limit of 10 ppbdue to background fluorescence. It was established that the quenching of carbazole in the presence of the CP system has a direct correlation to …

Freshwater Endmembers Impacting Carbonate Chemistry In The Mississippi Sound, Allison Savoie

Master's Theses

Coastal ecosystems are highly dynamic areas for carbon cycling and are likely to be negatively impacted by increasing ocean acidification. This research focused on dissolved inorganic carbon (DIC) and total alkalinity (TA) in the Mississippi Sound in order to understand the influence of local rivers that supply alkalinity to the area and buffer against ocean acidification. This area receives large fluxes of freshwater from local rivers, in addition to episodic inputs from the Mississippi River through a human-built diversion, the Bonnet Carré Spillway. Sites in the Mississippi Sound were sampled monthly during August 2018 to November 2019 and at weekly …

Directed Evolution Of Macrocyclic Peptides For Inhibition Of Autophagy, Joshua Gray

Dissertations and Theses (Open Access)

In recent decades it has become increasingly clear that induction of autophagy plays an important role in the development of treatment resistance and dormancy in many cancer types. Chloroquine (CQ) and hydroxychloroquine (HCQ), two autophagy inhibitors in clinical trials, suffer from poor pharmacokinetics and high toxicity at therapeutic dosages. This has prompted intense interest in the development of targeted autophagy inhibitors to re-sensitize disease to treatment with minimal impact on normal tissue. We utilized Scanning Unnatural Protease Resistant (SUPR) mRNA display to develop macrocyclic peptides targeting the autophagy protein LC3. The resulting peptides bound LC3A and LC3B—two essential components of …

Connexin-46/50 In A Dynamic Lipid Environment Resolved By Cryoem At 1.9 Å, Jonathan A. Flores, Bassam G. Haddad, Kimberly A. Dolan, Janette Bernadette Myers, Craig C. Yoshioka, Jeremy Yoshioka, Daniel M. Zuckerman, Steve L. Reichow

Chemistry Faculty Publications and Presentations

Gap junctions establish direct pathways for cells to transfer metabolic and electrical messages. The local lipid environment is known to affect the structure, stability and intercellular channel activity of gap junctions; however, the molecular basis for these effects remains unknown. Here, we incorporate native connexin-46/50 (Cx46/50) intercellular channels into a dual lipid nanodisc system, mimicking a native cell-to-cell junction. Structural characterization by CryoEM reveals a lipid-induced stabilization to the channel, resulting in a 3D reconstruction at 1.9 Å resolution. Together with all-atom molecular dynamics simulations, it is shown that Cx46/50 in turn imparts long-range stabilization to the dynamic local lipid …

Enhancement Of Graphene Biocompatibility As A Potential Nano-Carrier For Drug Delivery Applications Using Natural Deep Eutectic Solvent, Zainal Abidin Mohamad Hamdi

Student Works (2020-2029)

Graphene has attracted massive interest in numerous biomedical applications such as anti-cancer therapy, drug delivery, bio-imaging and gene delivery. Therefore, it is important to ensure that graphene is nontoxic, and that its cellular biological behavior is safe and biocompatible. Herein, a new route was used to enhance the biocompatibility of graphene as a nano-carrier for potential drug delivery applications, using different compositions of natural deep eutectic solvents (DESs) as functionalizing agents, owing to their capability to introduce various functional groups and surface modifications. To meet this end, eight different combinations of binary and ternary DESs were synthesized using choline chloride …

Antibacterial Coatings Derived From Novel Chemically Responsive Vesicles, Emily B. Mobley

Master's Theses

In order for a drug, or any material used for the purpose of eliciting a change in an organisms’ physical or chemical state, to be effective it must reach the intended target intact and for a sustained rate over time. Drug delivery systems encapsulate a drug to protect it from degradation, prevent side reactions, increase solubility, improve accumulation rates at target sites, and release drugs at a controlled rate. Controlled and sustained release of drugs is achieved by degradation of the carrier triggered by breaking dynamic chemical bonds caused by changes in the chemical environment such as pH or redox …

Mxenes As Flow Electrodes For Capacitive Deionization Of Wastewater, Naqsh E. Mansoor

Boise State University Theses and Dissertations

The energy-water nexus poses an integrated research challenge, while opening up an opportunity space for the development of energy efficient technologies for water remediation. Capacitive Deionization (CDI) is an upcoming reclamation technology that uses a small applied voltage applied across electrodes to electrophoretically remove dissolved ionic impurities from wastewater streams. Similar to a supercapacitor, the ions are stored in the electric double layer of the electrodes. Reversing the polarity of applied voltage enables recovery of the removed ionic impurities, allowing for recycling and reuse. Simultaneous materials recovery and water reclamation makes CDI energy efficient and resource conservative, with potential to …

Testing Flowering Perennial Plants In A Bermudagrass (Cynodon Spp.) Lawn, Paige Elizabeth Boyle, Michelle Wisdom

Horticulture Faculty Publications and Presentations

Most pollinating insects require a season-long succession of floral resources to fulfill life-cycle requirements. Incorporating forbs into turfgrass sites may create a season-long sequence of flowers to support foraging pollinators. However, persistence of forbs in warm-season turfgrasses such as bermudagrass (Cynodon spp.) may be affected by the competitive nature of the turfgrass and routine management practices such as mowing. A 2-year study was conducted to evaluate seven forbs (Bellis perennis L., Lotus corniculatus L., Prunella vulgaris L., Trifolium fragiferum L. ‘Fresa’, Trifolium repens L. ‘Durana’ and ‘Resolute’, Trifolium subterraneum L.) for persistence and ability to produce floral resources …

Chemistry And Biochemistry Authored Faculty Publications: Snapshot Of The Ranking Of Journals In Which They Published Based On Data From Journal Citation Reports (Jcr), Lutishoor Salisbury, Yang Tian, Jeremy Smith

University Libraries Faculty Publications and Presentations

This report presents a snapshot of the research output of the Chemistry and Biochemistry Department at the University of Arkansas for the period 2015-2019. The contents of the report were generated using Web of Science Core Collection databases and the Journal Citation Report only. It highlights the journals in which the researchers published and the ranking of those journals.