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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 …

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 …

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 …

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 …

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 …

Cooperative Lewis Pairs Based On High-Valent Early Transition Metal Halides And Synthesis Of Their Nitride Complexes, Md. Mamdudur Rahman

Theses and Dissertations

Herein, we report the activation of relatively strong C–H and C–O bonds under mild conditions by a cooperative interaction of TaCl5 and PPh3. An unprecedented activation of nitrile adducts of high-valent transition metals with the formation of novel zwitterionic imido complexes was observed. The scope of the reaction includes a range of substituted unactivated nitriles including the C–H bond activation of both aliphatic and aromatic nitriles.

The cooperative action of a Lewis acidic high-valent transition metal halide (TaCl5 or NbCl5) and a weakly nucleophilic base (NEt3 or PPh3) leads to the deprotonation of a coordinated nitrile and subsequent rearrangement to …

Nanoparticles With Tunable Fluorophobic Effect Towards Multimodal Coassembly With Block Copolymers, Zachary Michael Marsh

Theses and Dissertations

Nanomaterials are often fabricated using block polymers to direct the placement of nanoparticles via selective intermolecular interactions such as hydrogen bonding. Fluorophobic interactions have emerged as a promising handle to control nanoparticle placement independently from typical hydrophilic approaches. A series of nanoparticles with tunable fluorophobicity were prepared to elucidate the key parameters for harnessing fluorophobic interactions in this context. Mixed ligand fluorinated nanoparticles (ML-FNPs) where prepared to examine the competing roles of each ligand towards fluorophobicity and solubility. The ML-FNP intermolecular interactions were first studied using a custom-made Quartz Crystalline Microbalance (QCM) based technique. The ML-FNPs were then examined for …

Time-Resolved Photoluminescence Of 6-Thienyl-Lumazine Flourophore In Cellulose Acetate Nanofibers For Detection Of Mercury Ions, Noura A. Al Shamisi

Chemistry Theses

Time-resolved photoluminescence measurements were used to characterize the photophysical properties of 6-thienyllumazine (TLm) fluorophores in cellulose acetate nanofibers (NFs) in the presence and absence of mercuric acetate salts. In solution, excited-state proton transfer (ESPT) from TLm to water molecules was observed at pH from 2 to 12. The insertion of the thienyl group into lumazine (Lm) introduces cis and trans conformers while keeping the same tautomerization structures. Global and target analysis was employed to resolve the true emission spectra of all prototropic, tautomeric, and rotameric species for TLm in water. However, in the NFs solid film no ESPT from TLm …

Development Of A New Analytical Method For Separation And Quantitative Determination Of Synthetic Cathinones In Urine Using Gas Chromatography Tandem Mass Spectrometry, Jasim Ali Ali Alzaabi

Chemistry Theses

This thesis is concerned with a new class of drugs known as synthetic cathinones, which overruns the drug markets in recent years as “legal highs” drugs, under different commercial names such as bath salts. All synthetic cathinone derivatives consist of a chiral center and usually sold out as a racemic mixture. Usually, one of the two enantiomers will have stronger central nervous system (CNS) stimulatory activity and the other one may have no significant CNS activity or addictive properties. A new sensitive and selective analytical method was developed for the simultaneous determination of ten synthetic cathinones enantiomers in spiked urine …

Metal-Organic Frameworks: Photophysics, Energy Transfer, And Electronic Structure, Ekaterina A. Dolgopolova

Theses and Dissertations

The current landscape of technological and industrial related fields is looking for novel materials with enhanced performances, which will not only improve various fields in science, but also can ensure increased environmental safety. Recently, metal-organic frameworks (MOFs) have been shown as a promising type of material for a wide range of applications including gas storage and separation, sensing, and heterogeneous catalysis. The main advantages of MOFs rely on their modular structures as well as their porosity. For instance, the modular nature of MOFs provides a control over chromophore arrangement, systematic tuning of ligand design and synthetic conditions allowing one to …

Structural And Functional Studies On 4-Hydroxy- Tetrahydrodipicolinate Reductase: Potential Drug Target In Bacteria, Swanandi Pote

Theses and Dissertations

Antimicrobial resistance has become an alarming public health concern since early 2000’s. Infections caused by multidrug resistant bacteria not only increase the mortality rate but also increase the economic burden globally. One approach to alleviate this issue is to find novel drug targets. In this regard, the bacterial lysine biosynthesis pathway provides several targets that may be used for design of antimicrobial compounds. Bacteria use lysine or meso-diaminopimelate to crosslink the peptidoglycan monomers in the bacterial cell wall. As such, we hypothesize that blocking this pathway will induce defects in the bacterial cell wall that are similar to those …

Study Of The Effects Of Silver Ions And Silver Nanoparticles On Embryonic Development, Martha Sharisha Johnson

Biomedical Sciences Theses & Dissertations

This dissertation focuses on the study of the toxicity of metal nanoparticles (NPs) and their ions on the development of zebrafish embryos, aiming to understand unique biological effects of NPs and ions, and design new in vivo assays to characterize the toxicity of these metal NPs and metal ions. Currently, the underlying molecular mechanisms of biological effects of nanomaterials are partially understood. Some studies assume that the toxic effects of NPs can be attributed to the release of their ions. We investigate the effects of silver NPs (Ag NPs) and silver ions (Ag+ ions) on the embryonic development of zebrafish …

Synthesis And Biological Applications Of Some Novel Urea And Thiourea-Quinoline Derivatives, Aysha Mohammed Alkaabi

Theses

Extensive literature survey reveals that 8-Hydroxyquinoline (8-HQ), urea, thiourea and piperazine exhibit wide biological activity profile such as anticancer, anti-Alzheimer, anti-viral, antibacterial and antifungal activity. Novel urea and thiourea-quinoline derivatives connected by piperazine moiety have been synthesized and purified using appropriate techniques (extraction, crystallization and column chromatography) followed by characterization using IR spectroscopy and NMR spectroscopy (both ¹H and ¹³C).

Biological activity, metal chelation properties and the photo-physical properties were studied for these novel compounds. Anti-bacterial study shows moderate activity for most of the compounds against P.aereginosa, S.aureus and Enterococcus at concentration 250 μM. Antifungal study showed …

Synthesis And Biological Applications Of Some Novel Urea And Thiourea-Benzimidazole Derivatives, Lamia Ali Siddig

Theses

The objective of this research is the synthesis and characterization of novel urea and thiourea-benzimidazole derivatives and to test their biological activities. The 17 novel compounds (57a-j), (58a-d), 62, 63, and 65 have been synthesized, purified by different techniques such as extraction and column chromatography, and then characterized by using suitable spectroscopic techniques including ^¹H-NMR, ¹³C-NMR, fluorescence, and IR spectroscopy techniques.

The biological activity of these compounds has been studied. The antibacterial activity was evaluated at different concentrations (μg/ ml) against 6 types of bacteria (Esherichia coli, Pseudomonas aeruginosa, Salmonella enterica, Klebsiella pneumoniae, Staphylococcus aureus …

3-Hydroxyflavones And 3-Hydroxy-4-Oxoquinolines As Carbon Monoxide-Releasing Molecules, Tatiana Soboleva, Lisa M. Berreau

Chemistry and Biochemistry Faculty Publications

Carbon monoxide-releasing molecules (CORMs) that enable the delivery of controlled amounts of CO are of strong current interest for applications in biological systems. In this review, we examine the various conditions under which CO is released from 3-hydroxyflavones and 3-hydroxy-4-oxoquinolines to advance the understanding of how these molecules, or derivatives thereof, may be developed as CORMs. Enzymatic pathways from quercetin dioxygenases and 3-hydroxy-4-oxoquinoline dioxygenases leading to CO release are examined, along with model systems for these enzymes. Base-catalyzed and non-redox-metal promoted CO release, as well as UV and visible light-driven CO release from 3-hydroxyflavones and 3-hydroxy-4-oxoquinolines, are summarized. The visible …

Optical Stability Of 1,1′-Binaphthyl Derivatives, Nikolay V. Tkachenko, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The racemization process of various 1,1′-binaphthyl derivatives is studied by quantum calculations. The preferred racemization pathway passes through a transition state belonging to the C_i symmetry group. The energy barrier for this process is independent of solvation, the electron-withdrawing/releasing power of substituents, or their ability to engage in H-bonds within the molecule. The primary factor is instead the substituent size. The barrier is thus reduced when the −OH groups of 1,1′-bi-2-naphthol are replaced by H. There is a drop in the barrier also when the substituents are moved from the 2,2′ positions to 6,6′, where they will not come …

Synthesis And Metalation Of Internally Alkylated Porphyrinoids, Alissa Nicole Latham

Theses and Dissertations

The mechanism behind alkyl migration in palladium(II) benzocarbaporphyrins was investigated through the synthesis of a 23-methylcarbaporphyrin. It was found that palladium insertion led to methyl group migration to C21 and it is proposed that this occurs through an oxidative addition onto the palladium metal center, followed by a reductive elimination to transfer the methyl to the internal carbon. A similar rearrangement was observed when 23-methylcarbaporphyrin was reacted with [Rh(CO)2Cl]2 and resulted in the formation of a rhodium(III) complex containing a three-membered rhodacycle. The syntheses of rhodium(I) and rhodium(III) derivatives of other carbaporphyrins, including 21- and 22-methylbenzo-carbaporphyrins, were probed and four …

Protein-Polymer Conjugates Synthesized Using Water-Soluble Azlactone-Functionalized Polymers Enable Receptor-Specific Cellular Uptake Toward Targeted Drug Delivery, Julia S. Kim, Allison R. Sirois, Analia J. Vazquez Cegla, Eugenie Jumai'an, Naomi Murata, Maren E. Buck, Sarah J. Moore

Chemistry: Faculty Publications

Conjugation of proteins to drug-loaded polymeric structures is an attractive strategy for facilitating target-specific drug delivery for a variety of clinical needs. Polymers currently available for conjugation to proteins generally have limited chemical versatility for subsequent drug loading. Many polymers that do have chemical functionality useful for drug loading are often insoluble in water, making it difficult to synthesize functional protein–polymer conjugates for targeted drug delivery. In this work, we demonstrate that reactive, azlactone-functionalized polymers can be grafted to proteins, conjugated to a small-molecule fluorophore, and subsequently internalized into cells in a receptor-specific manner. Poly(2-vinyl-4,4-dimethylazlactone), synthesized using reversible addition–fragmentation chain …

Revisiting Volumes Of Lipid Components In Bilayers, John F. Nagle, Richard M. Venable, Ezekiel Maroclo-Kemmerling, Stephanie Tristram-Nagle

University Faculty Publications and Creative Works

In addition to obtaining the highly precise volumes of lipids in lipid bilayers, it has been desirable to obtain the volumes of parts of each lipid, such as the methylenes and terminal methyls on the hydrocarbon chains and the head group. Obtaining such component volumes from experiment and from simulations is re-examined, first by distinguishing methods based on apparent versus partial molar volumes. Although somewhat different, both these methods give results that are counterintuitive and that differ from results obtained by a more local method that can only be applied to simulations. These comparisons reveal differences in the average methylene …

Production Of Secondary Organic Aerosol During Aging Of Biomass Burning Smoke From Fresh Fuels And Its Relationship To Voc Precursors, A. T. Ahern, E. S. Robinson, D. S. Tkacik, R. Saleh, L. E. Hatch, K. C. Barsanti, C. E. Stockwell, R. J. Yokelson, A. A. Presto, A. L. Robinson, R. C. Sullivan, N. M. Donahue

Chemistry and Biochemistry Faculty Publications

After smoke from burning biomass is emitted into the atmosphere, chemical and physical processes change the composition and amount of organic aerosol present in the aged, diluted plume. During the fourth Fire Lab at Missoula Experiment, we performed smog-chamber experiments to investigate formation of secondary organic aerosol (SOA) and multiphase oxidation of primary organic aerosol (POA). We simulated atmospheric aging of diluted smoke from a variety of biomass fuels while measuring particle composition using high-resolution aerosol mass spectrometry. We quantified SOA formation using a tracer ion for low-volatility POA as a reference standard (akin to a naturally occurring internal standard). …

Deswelling Induced Morphological Changes In Dual Ph And Temperature Responsive Ultra-Low Crosslinked Poly (N-Isopropyl Acrylamide)-Co-Acrylic Acid Microgels, Molla R. Islam, Maddie Tumbarello, L. Andrew Lyon

Engineering Faculty Articles and Research

Poly(N-isopropylacrylamide) microgels prepared without exogenous cross-linker are extremely “soft” as a result of their very low cross-linking density, with network connectivity arising only from the self-crosslinking of pNIPAm chains. As a result of this extreme softness, our group and others have taken interest in using these materials in a variety of bioengineering applications, while also pursuing studies of their fundamental properties. Here, we report deswelling triggered structural changes in poly(N-isopropylacrylamide-co-acrylic acid) (ULC10AAc) microgels prepared by precipitation polymerization. Dynamic light scattering suggests that the deswelling of these particles not only depends on the collapse of …

Ethanolamine Regulates Cqsr Quorum-Sensing Signaling In Vibrio Cholerae, Samit Watve, Kelsey Barrasso, Sarah A. Jung, Kristen J. Davis, Lisa A. Hawver, Atul Khataokar, Ryan G. Palaganas, Matthew B. Neiditch, Lark Perez, Wai-Leung Ng

College of Science & Mathematics Departmental Research

The pathogen that causes cholera, Vibrio cholerae, uses the cell-cell communication process known as quorum sensing (QS) to regulate virulence factor production and biofilm formation in response to changes in population density and complexity. QS is mediated through the detection of extracellular chemical signals called autoinducers. Four histidine kinases, LuxPQ, CqsS, CqsR and VpsS, have been identified as receptors to activate the key QS regulator LuxO at low cell density. At high cell density, detection of autoinducers by these receptors leads to deactivation of LuxO, resulting in population-wide gene expression changes. While the cognate autoinducers that regulate the activity of …

In Situ Measurements Of Trace Gases, Pm, And Aerosol Optical Properties During The 2017 Nw Us Wildfire Smoke Event, Vanessa Selimovic, Robert J. Yokelson, Gavin R. Mcmeeking, Sarah Coefield

Chemistry and Biochemistry Faculty Publications

In mid-August through mid-September of 2017 a major wildfire smoke and haze episode strongly impacted most of the NW US and SW Canada. During this period our ground-based site in Missoula, Montana, experienced heavy smoke impacts for ∼ 500h (up to 471μ-3 hourly average PM2.5). We measured wildfire trace gases, PM2.5 (particulate matter ≤2.5μm in diameter), and black carbon and submicron aerosol scattering and absorption at 870 and 401nm. This may be the most extensive real-time data for these wildfire smoke properties to date. Our range of trace gas ratios for δNH3 δCO and δC2H4 δCO confirmed that the smoke …