Digital Commons Network^™

On-Trap Derivatization Of Short-Chain Fatty Acids, Mace Mattieson

Master's Theses and Doctoral Dissertations

It has recently been hypothesized that gastrointestinal microbiota modulate immune response by the production of short-chain fatty acids (SCFAs). There is a need for rapid, selective analytical methodology capable of trace analysis of SCFAs in complex biological matrices. Previous studies by others using multibed-sorbent traps, solid phase microextraction (SPME), and on-fiber derivatization with SPME showed that it is possible to achieve low limits of detection (LODs) for the gas chromatographic (GC) headspace analysis of SCFAs. The goal of this project was to achieve on-trap derivatization of SCFAs by incorporating a derivatizing agent onto a sorbent trap. Preconcentration and derivatization of …

Comparison Of Standard Impedance Spectroscopy Response To Aqueous Metal Ions Using Plain Vs. Surface Derivatized Gold Interdigitated Electrodes, Sindhu Yalamanchili

Master's Theses and Doctoral Dissertations

Abstract Recent work has provided evidence that 5-amino-1, 10 –phenanthroline can react with CS2 to anchor on the gold surface of an interdigitated electrode (IDE) through a dithiocarbamate linkage, resulting in significant changes in impedance response in the presence of Cu2+ solutions. However, questions regarding the stability of the primary amine-based dithiocarbamate self-assembled monolayer, reproducibility of the raw impedance and phase angle data, and possible variation of the background response for the gold IDE array in solutions of different metal ions remain an issue. Primary experimental emphasis is on the reproducibility of standard impedance and phase angle data for the …

Theoretical Characterization Of Non-Covalent Weakly Bound Clusters Through The Application Of Sophisticated Computational Quantum Chemistry Methodologies And The Development Of Integrated Fragmentation Techniques, Desiree Bates

Electronic Theses and Dissertations

Non-covalent, weakly bound clusters have been and remain of significant interest to many researchers. However, with computational studies, accurate description of these interactions requires sophisticated electronic structure methods employing large basis sets. This methodology becomes extremely computationally demanding as the size of the system increases. This work presents benchmark data and explores methods for obtaining highly accurate ab initio results for larger systems at greatly reduced computational costs. CCSD(T) complete basis set limit interaction energies are presented for a variety of parallel-slipped π...π dimers and low-lying isomers of (h₂o)₆. The calibration of a 2-body:Many-body fragmentation method …

Isolation And Analysis Of Peptides Binding To Helix 69 Of E. Coli 23 S Rrna From M13 Phage Display, Moninderpal Kaur

Wayne State University Dissertations

Peptides binding to helix 69 of domain IV or residues 1906-1924, of 23 S rRNA of E.coli were being selected from a heptapeptide phage library. An experimental system including biotin labeling of RNA and then affinity selection through four rounds was being followed. After sequencing phage clones of the fourth round, two peptide sequences dominated the phage pool, STYTSVS and NQVANHQ. The later sequence was a unique sequence since this sequence contained an abundance of amino acid residues that are also present in the ribosome recycling factor, RRF, and known to make contacts with H69. Phage-display methodology demonstrated the rapid …

Characterization Of Intermolecular Pi-Type Interactions Using Sophisticated Quantum Mechanical, Electronic Structure Computations, Emily Joy Carrell

Electronic Theses and Dissertations

Much like the instrumentation in an experimental lab, computational chemists use computers to solve the mathematical equations that describe the physics of electrons to understand the chemistry involved. The combination of the two main components of computational chemistry, the basis set and method, determines the ``cost'' (disk, memory, and CPU time) of a computation. A variety of basis sets and methods have been developed in the past century. The focus of this report is to accurately describe non-covalent interactions with the use of various quantum computational techniques. In Chapter 1 a brief discussion on the theory behind computational chemistry is …

Gemini Metallo-Surfactants: Chemical And Physical Properties, Erich Ivan Valenzuela

Open Access Theses & Dissertations

Gemini surfactants are amphiphilic molecules that consist of two surfactant molecules chemically joined together by a spacer group. These molecules tend to self‐assemble into vesicles at much lower concentrations than traditional surfactants and have found many applications in catalysis, adsorption applications, drug‐delivery, nanoscale technology, and biotechnology. In this thesis, the synthesis, characterization and physical properties of a new type of Gemini surfactant derived from dinuclear Cu(II) metal complexes is presented. We call these molecules Gemini Metal‐Organic Surfactants (GMOs).

Three newly developed new GMOs (compounds 1‐3) are composed of Cu(II) ions ligated to a lipid‐functionalized triamine group and the metals are …

Modified Chromenes As Precursors To Taar Regulators, Jonathan Lehmann, Matthew Hart

Student Summer Scholars Manuscripts

200 million people worldwide are living with a thyroid disorder related to a hormonal imbalance. Symptoms of this imbalance include deviations from normal heart rates and metabolic rates. A chemical messenger known as T3 has been shown to raise cardiac and metabolic rates, but this takes place on a timescale of hours. However, recent discoveries have revealed that a different thyroid hormone known as T1AM is capable of affecting some of these same physiological conditions in a matter of minutes. T1AM is a potent, selective agonist for the Trace Amine Associated Receptor (TAAR). Several studies have probed the structural basis …

Quantum Chemical Analysis Of The Pka's Of Alcohols And A Cellular Automata Model For The Distribution Of Gases In The Earth's Atmosphere, Edur Basha Boyinipalli

Browse all Theses and Dissertations

Alcohols play important roles in many chemical and biological processes, and their acid/base behaviors are often important for these roles. In this study we ask the question, "Can the electronic properties of these compounds offer clues to the compounds' acid/base behaviors?" The study considers whether selected quantum chemical properties can be used to find correlations with the experimental pKa's of the alcohols (aliphatic and aromatic). Calculations were carried out for these alcohols using the semi-empirical RM1 method and the more advanced density functional theory (DFT) B3LYP/6-31+G* method. Significant correlations were found for several quantum chemical descriptors. It was also found …

Near Equilibrium Dissolution Of Calcite Using A Flow-Through Reactor (Ftr), Michael Mante

Browse all Theses and Dissertations

In mineral dissolution reactions, surface morphologies play important roles particularly in near equilibrium fluids where generation of new sites of reactivity (e.g., pit nuclei) is thermodynamically disfavored. Following CO₂ injection in geologic formations, dissolution of primary carbonate minerals and crack-sealing cements will occur. The impact of these reactions on fluid chemistry requires better understanding of the reaction kinetics of major minerals at close-to-equilibrium conditions. Initial investigations have focused on quantifying calcite dissolution using short residence time (~ 10 min) flow through reactors to obtain dissolution rates at 60°C, pH = 8.33 and Pco₂ = 3.8 x 10^{-4 …}

Synthesis Of Isatin Derivatives Used For The Inhibition Of Pro-Apoptotic Jurkat T Cells, Charles Michael Clay

Browse all Theses and Dissertations

A range of substituted 1H-indole-2,3-diones (isatins) was synthesized to assess their capability to inhibit caspases and prevent apoptosis in Jurkat T cells. The key steps in the synthesis of such molecules involved electrophilic substitution of the C-5 position of the isatin nucleus (if necessary), N-alkylation, Wolff-Kishner reduction of the C-3 carbonyl group and finally, Knoevenagel condensation. The design and synthesis of such potential inhibitors was guided by SAR studies of peptide based inhibitors such as "Q-VD-O-Ph", as well as small-molecule inhibitors based upon the isatins scaffold. Previously, 3-(2,6-difluorobenzylidene)-5-nitroindolin-2-one has been shown to inhibit apoptosis in human Jurkat T cells at …

Cetyltrimethylammonium Halide-Coated Electrodes For The Detection Of Dopamine In The Presence Of Interferents, Amber J. Yeary

Browse all Theses and Dissertations

Specially constructed carbon paste electrodes were coated with 10 mM cetyltrimethylammonium halide (CTAX) solutions, bromide and chloride being the counter anions. These surfactant modified electrodes were used to detect the catecholamine neurotransmitter dopamine using cyclic voltammetry. The coated electrodes gave reproducible quasi-reversible behavior for the analyte dopamine over a range of concentrations from 1 mM to 200 mM. When combined in solution with common interferents ascorbic acid (1 mM) and uric acid (300 μM), all cathodic and anodic current peaks maintained resolution at the biological pH of 7.4. When the coating solutions were below the critical micelle concentration (0.5 mM), …

Routes To Acylated Sydnone Esters, Amanda Marie Balaguer

Browse all Theses and Dissertations

Various 4-acyl-3-[2'-(carboalkoxy)phenyl]sydnones were synthesized by reaction of the parent sydnone with the corresponding anhydrides and Montmorillonite K-10. In the Q-tube, the acylation using acetic anhydride, which normally took 1.5 days for complete conversion thermally, was complete in 8.5 hours. Use of bismuth triflate as catalyst reduced the reaction time to 5 hours and, in the microwave, reactions were complete in 30 minutes and provided comparable yields. New sydnones were synthesized with acetic, propionic, butyric, and isobutyric anhydrides. Extension to various homogeneous metal triflates (lanthanum, yttrium, scandium, hafnium, gadolinium, and indium) was explored. Reactions were performed with 3-phenylsydnone as reactant, initially …

Uranyl Reactions With Dithionite, L-Ascorbic Acid, And Supported Nanosized Zero-Valent Iron, Shanna Estes

All Theses

This work examined several reductants for remediation of low pH aqueous uranium contamination by reductive precipitation. Reductants included sodium dithionite, L-ascorbic acid, and nanosized zero-valent iron (nZVI). Additionally, the reductive capacity of nZVI successfully entrapped within a silicate matrix (cryogel) was also examined. This supported nZVI is expected to increase nZVI stability in the subsurface, and to provide a convenient in situ delivery mechanism for other remediation systems which may combine entrapped reductant and catalyst.
Fluorescence and absorbance spectroscopy were used to investigate the interaction between hexavalent uranium (U(VI), uranyl) and both sodium dithionite and L-ascorbic acid at pH 2. …

Ultrafast Rempi In Benzene And The Monohalobenzenes Without The Focal Volume Effect, Timothy D. Scarborough, James Strohaber, David B. Foote, Collin J. Mcacy, Cornelis J. Uiterwaal

C.J.G.J. Uiterwaal Publications

We report on the photoionization and photofragmentation of benzene (C₆H₆) and of the monohalobenzenes C₆H₅–X (X = F, Cl, Br, I) under intense-field, single-molecule conditions. We focus 50-fs, 804-nm pulses from a Ti:sapphire laser source, and record ion mass spectra as a function of intensity in the range ~10¹³ W/cm² to ~10¹⁵ W/cm². We count ions that were created in the central, most intense part of the focal area; ions from other regions are rejected. For all targets, stable parent ions (C₆H₅X+) are …

Human Fatty Acid Transport Protein 2a/Very Long Chain Acyl-Coa Synthetase 1 (Fatp2a/Acsvl1) Has A Preference In Mediating The Channeling Of Exogenous N-3 Fatty Acids Into Phosphatidylinositol, Elaina M. Melton, Ronald Cerny, Paul A. Watkins, Concetta C. Dirusso, Paul N. Black

Ronald Cerny Publications

The trafficking of fatty acids across the membrane and into downstream metabolic pathways requires their activation to CoA thioesters. Members of the fatty acid transport protein/ very long chain acyl-CoA synthetase (FATP/Acsvl) family are emerging as key players in the trafficking of exogenous fatty acids into the cell and in intracellular fatty acid homeostasis.We have expressed two naturally occurring splice variants of human FATP2 (Acsvl1) in yeast and 293T-REx cells and addressed their roles in fatty acid transport, activation, and intracellular trafficking. Although both forms (FATP2a (Mr 70,000) and FATP2b (Mr 65,000 and lacking exon3, which encodes part of the …

Overexpression Of Galnac-Transferase Galnac-T3 Promotes Pancreatic Cancer Cell Growth, Keisuke Taniuchi, Ronald Cerny, Aki Tanouchi, Kimitoshi Kohno, Norihiro Kotani, Koichi Honke, Toshiji Saibara, Michael A. Hollingsworth

Ronald Cerny Publications

O-linked glycans of secreted and membrane bound proteins play an important role in the pathogenesis of pancreatic cancer by modulating immune responses, inflammation, and tumorigenesis. A critical aspect of O-glycosylation, the position at which proteins are glycosylated with N-acetyl-galactosamine on serine and threonine residues, is regulated by the substrate specificity of UDP-GalNAc: polypeptide N-acetylgalactosaminyl-transferases (GalNAc-Ts). Thus, GalNAc-Ts regulate the first committed step in O-glycosylated protein biosynthesis, determine sites of O-glycosylation on proteins, and are important for understanding normal and carcinoma-associated O-glycosylation. We have found that one of these enzymes, GalNAc-T3, is overexpressed in …

Identification And Characterization Of The Anti-Methicillin-Resistant Staphylococcus Aureus Wap-8294a2 Biosynthetic Gene Cluster From Lysobacter Enzymogenes Oh11, Wei Zhang, Yaoyao Li, Guoliang Qian, Yan Wang, Haotong Chen, Yue-Zhong Li, Fengquan Liu, Yuemao Shen, Liangcheng Du

Department of Chemistry: Faculty Publications

Lysobactor enzymogenes strain OH11 is an emerging biological control agent of fungal and bacterial diseases. We recently completed its genome sequence and found it contains a large number of gene clusters putatively responsible for the biosynthesis of nonribosomal peptides and polyketides, including the previously identified antifungal dihydromaltophilin (HSAF). One of the gene clusters contains two huge open reading frames, together encoding 12 modules of nonribosomal peptide synthetases (NRPS). Gene disruption of one of the NRPS led to the disappearance of a metabolite produced in the wild type and the elimination of its antibacterial activity. The metabolite and antibacterial activity were …

Characterizing Rna Dynamics At Atomic Resolution Using Solution-State Nmr Spectroscopy, Jameson R. Bothe, Evgenia N. Nikolova, Catherine D. Eichhorn, Jeetender Chugh, Alexandar L. Hansen, Hashim M. Al-Hashimi

Department of Chemistry: Faculty Publications

Many recently discovered non-coding RNAs do not fold into a single native conformation, but rather, sample many different conformations along their free energy landscape to carry out their biological function. Unprecedented insights into the RNA dynamic structure landscape are provided by solution-state NMR techniques that measure the structural, kinetic, and thermodynamic characteristics of motions spanning picosecond to second timescales at atomic resolution. From these studies a basic description of the RNA dynamic structure landscape is emerging, bringing new insights into how RNA structures change to carry out their function as well as applications in RNA-targeted drug discovery and RNA bioengineering.

Strategies For Labeling Proteins With Paracest Agents, Olga Vasalatiy, Piyu Zhao, Mark Woods, Andrei Marconescu, Aminta Castillo-Muzquiz, Philip Thorpe, Garry Kiefer, A. Dean Sherry

Chemistry Faculty Publications and Presentations

Reactive surface lysine groups on the chimeric monoclonal antibody (3G4) and on human serum albumin (HSA) were labeled with two different PARACEST chelates. Between 7.4 – 10.1 chelates were added per 3G4 molecule and between 5.6 – 5.9 chelates per molecule of HSA, depending upon which conjugation chemistry was used. The immunoreactivity of 3G4 as measured by ELISA assays was highly dependent upon the number of attached chelates: 88% immunoreactivity with 7.4 chelates per antibody versus only 17% immunoreactivity with 10.1 chelates per antibody. Upon conjugation to 3G4, the bound water lifetime of Eu-1 increased only marginally, up from …

Inducible Nitric Oxide Synthase Provides Protection Against Injury-Induced Thrombosis In Female Mice, Rita K. Upmacis, Hao Shen, Lea Esther S. Benguigui, Brian D. Lamon, Ruba S. Deeb, Katherine A. Hajjar, David P. Hajjar

Faculty Papers and Publications

Nitric oxide (NO) is an important vasoactive molecule produced by three NO synthase (NOS) enzymes: neuronal (nNOS), inducible (iNOS) and endothelial NOS (eNOS). While eNOS contributes to blood vessel dilation that is generally thought to protect against the development of hypertension, iNOS has been primarily implicated as a disease-promoting isoform leading to protein-bound 3-nitrotyrosine formation in aortic lesions and select organs during atherogenesis. Despite this, iNOS may also play a physiological role, via the modulation of cyclooxygenase and thromboregulatory eicosanoid production. Herein, we examined the role of iNOS in a murine model of thrombosis. Blood flow was measured in carotid …

Synthesis Of Alkynyl Ribofuranosides, Christian Rodriguez

Dissertations and Theses

No abstract provided.

Methionine-35 Of Aβ(1-42): Importance For Oxidative Stress In Alzheimer Disease, D. Allan Butterfield, Rukhsana Sultana

Chemistry Faculty Publications

Alzheimer disease (AD) is an age-related progressive neurodegenerative disorder. This devastating disease is characterized by the presence of senile plaques (SP), neurofibrillary tangles (NFTs), and loss of synapses. Amyloid beta-peptide 1–42 (Aβ(1–42)) is the main component of SP and is pivotal to AD pathogenesis. Brain of subjects with AD and arguably its earliest manifestation, mild cognitive impairment (MCI), demonstrate increased levels of oxidative stress markers. Our laboratory combined these two aspects of AD and MCI and proposed the Aβ(1–42)-associated free radical oxidative stress hypothesis to explain oxidative stress under which the MCI and AD brain exist …

The Release Of Calcium In Bacillus Anthracis Pathogenicity, Natiera Magnuson, Manomita Patra, Maria Elena Reynaga, Ernesto Abel-Santos

McNair Poster Presentations

Bacillus anthracis spores form in response to starvation and can withstand extremes of heat, radiation, and chemical toxins, making B. anthracis spores ideal vehicles for infections.1 The resistance and dormancy of bacterial spores are dependent on a largely dehydrated core.2 The spore core is not only devoid of water, but contains between 0.8 to 1M calcium complexed with 2,6-pyridinedicarboxylic acid (dipicolinic acid, DPA). The DPA-calcium complex (CaDPA) helps protect DNA, RNA, and the metabolic enzymes needed for the establishment of a vegetative cell cytoplasm.3 An anthrax infection starts with the germination of B. anthracis spores in a macrophage.4 The germinated …

Synthesis, Assembly, And Characterization Of Monolayer-Protected Gold Nanoparticle Films For Protein Monolayer Electrochemistry,, Tran T. Doan, Michael H. Freeman, Adrienne R. Schmidt, Natalie T. Nguyen, Michael C. Leopold

Chemistry Faculty Publications

Colloidal gold nanoparticles protected with alkanethiolate ligands called monolayer protected gold clusters (MPCs) are synthesized and subsequently incorporated into film assemblies that serve as adsorption platforms for protein monolayer electrochemistry (PME). PME is utilized as the model system for studying electrochemical properties of redox proteins by confining them to an adsorption platform at a modified electrode, which also serves as a redox partner for electron transfer (ET) reactions. Studies have shown that gold nanoparticle film assemblies of this nature provide for a more homogeneous protein adsorption environment and promote ET without distance dependence compared to the more traditional systems modified …

Charge Saturation And Neutral Substitutions In Halomethanes And Their Group 14 Analogues, Bernard K. Wittmaack, Chad Crigger, Matthew Guarino, Kelling J. Donald

Chemistry Faculty Publications

A computational analysis of the charge distribution in halomethanes and their heavy analogues (MH_4-nX_n: M= C, Si, Ge, Sn, Pb; X = F, Cl, Br, I) as a function of _n uncovers a previously unidentified saturation limit for fluorides when M ≠ C. We examine the electron densities obtained at the CCSD, MP2(full), B3PW91, and HF levels of theory for 80 molecules for four different basis sets. A previously observed substituent independent charge at F in fluoromethanes is shown to be a move toward saturation that is restricted by the low polarizability of C. This limitation …

Method Developments To Analyze Caffeine And Acesulfame-K Concentrations In Natural Waters In And Around Charleston, Il, Usa, Laleen Bodhipaksha

Masters Theses

Analytical methods using batch solid phase extraction were developed for two chemical markers, caffeine and acesulfame-K, to assess anthropogenic water contamination of natural water bodies in and around Charleston, Illinois.

Measurements were conducted on 12 different extracted samples using reverse phase HPLC. Two creek samples showed the presence of acesulfame-K (0.45 ± 0.10 and 0.25 ± 0.06 ppb) and two creek samples showed the presence of caffeine (3 .1 ± 1.2 and 1.6 ± 0.6 ppb ). Effluent from the Charleston waste water treatment plant showed an acesulfame-K concentration of 0.67 ± 0.15 ppb.

These results indicate measurement of both …

Synthesis Of Molecular Containers Based On Modifications Of Resorcin(4)Arene And Calix(4)Arene, Anupama Makineni

Masters Theses

This research work was mainly focused on the synthesis of molecular containers based on modifications ofresorcin[4]arene and calix[4]arene.

The modifications of resorcin[ 4 ]arene include the attempts to attach a phthalimide featured linker onto the phenol hydroxyl groups of resorcin[4]arene. A few halogen leaving groups were used, including fluorine, chlorine, and bromine. The substitution with tetraflorophthalimide resulted in a mixture of regio-isomeric products, whereas for 4,5-dichloro- and 4,5-dibromophthalimides, no desired substitution product was formed. It was, however, discovered that both 4,5-dichloro- and 4,5-dibromophthalimides forms monoclinic crystals. The second modification of resorcin[4]arene focused on functionalizations of both upper and lower rims …

Self-Assembly And Photophysics Of Selected Organic Materials And Two-Photon Bioimaging With Profluorescent Nitroxides, Polyelectrolyte Nanoparticles, And Squaraine Probes, Hyo Yang Ahn

Electronic Theses and Dissertations

Two-photon absorption and upconverted fluorescence has been utilized in a variety of applications in pure science and engineering. Multiphoton-based techniques were used in this research in order to understand photophysical and chemical characteristics of several fluorescent dyes and to demonstrate some of their key applications. Two-photon fluorescence microscopy (2PFM) has become a powerful technique in bio-photonics for non-invasive imaging in the near-infrared (NIR) region (700~1000 nm) that often results in less photobleaching. In Chapter 1, there is a brief introduction to fluorescence, examples of fluorescence materials, and a discussion of the advantages of two-photon absorption. 2PFM imaging was utilized in …

The Application Of Two-Photon Absorbing Probes In Lysosomal, Zinc Ion Sensing And Folate Receptor-Targeted Bioimaging, Xuhua Wang

Electronic Theses and Dissertations

Two-photon fluorescence microscopy (2PFM) has become a powerful technique for bioimaging in non-invasive cancer diagnosis and also investigating the mechanization and original of a variety of diseases by tracking various biological processes. Because the fluorescence emission by two photon absorbing (2PA) is directly proportional to the square of the intensity of excitation light, this intrinsic property of 2PA provides 2PFM great advantages over traditional one-photon fluorescence microscopy (1PFM), including high 3D spatial localization, less photodamage and interference from biological tissue because of using longer wavelength excitation (700-1300 nm). However, most 2PA probes are hydrophobic and their photostabilities are questionable, severely …

The Unsuspected Pathway Of The Allosteric Transition In Hemoglobin, Stefan Fischer, Kenneth W. Olsen, Kwangho Nam, Martin Karplus

Chemistry: Faculty Publications and Other Works

Large conformational transitions play an essential role in the function of many proteins, but experiments do not provide the atomic details of the path followed in going from one end structure to the other. For the hemoglobin tetramer, the transition path between the unliganded (T) and tetraoxygenated (R) structures is not known, which limits our understanding of the cooperative mechanism in this classic allosteric system, where both tertiary and quaternary changes are involved. The conjugate peak refinement algorithm is used to compute an unbiased minimum energy path at atomic detail between the two end states. Although the results confirm some …