Digital Commons Network^™

Synthesis Of A Silsesquioxane Based Supramolecular Polymer, Rachel Bianculli

Honors Projects

Research toward smart materials, specifically self-healing polymers, is an expanding topic within the materials science field. These materials rely heavily on dynamic crosslinking that is achieved by inducing different degrees of hydrogen bonding, van der Waals forces, etc. This work, demonstrated by research previously done within the Ostrowski research group, shows how coordination bonds of transition metals have been shown to create light activated, self-healing properties. Work done with these light-activated chromium (III) complexes with a poly(butylyene-co-ethylene) backbone have shown how metal—ligand coordination geometries can tune mechanical properties of the polymeric material. However, these materials suffer from being incredibly soft …

Electrochemical Oxidation Of P-Chlorophenol On Porous Ti/Bdd Electrode Cooperated With Cathode Dechlorination, Rong-Ling Chen, Wei-Min Huang, Ya-Peng He, Jun Shi, Hai-Bo Lin

Journal of Electrochemistry

The electrochemical oxidation of p-chlorophenol on porous Ti/BDD electrode cooperated with synergistic effect of cathode dechlorination was studied. Electrochemical degradation tests of p-chlorophenol were conducted in single and double compartment electrolytic cells separately, and the results showed that the mineralization happened mainly in the anode region. The product of chloride ions produced from the cathodic reduction of 4-chlorophenol in the single cell migrated to the anode region and further generated active chlorine toward electro-catalytic oxidation. At the same time, the chloride ion produced from the cathode of the double cell was difficult to be migrated to the anode region, which …

Solid-Phase Synthesis Of Azole-Comprising Peptidomimetics And Coordination Of A Designed Analog To Zn2+, Aanchal Mohan, Allyson H. M. Koh, Gregory Gate, Anna L. Calkins, Kyra N. Mccomas, Amelia A. Fuller

Chemistry and Biochemistry

Peptidomimetics that can coordinate transition metals have a variety of potential applications as catalysts, sensors, or materials. A new modular peptidomimetic scaffold, the “azole peptoid”, is introduced here. We report methods for the solid-phase synthesis of eleven examples of trimeric N-substituted oligoamides that include oxazole- or thiazole-functionalized backbones. The products prepared comprise a diversity of functionality, including a metal-coordinating terpyridine group. The modular synthetic approach enables ready preparation of analogs for specific applications. To highlight a potential use of this new synthetic scaffold, a trimeric azole peptoid functionalized with a terpyridine residue was prepared and studied. The characteristic 2:1 ligand:metal …

Preparation And Properties Of Manganese Oxide And Polyaniline-Carbon Composite Electrode, Tian-Tian Zhou, Bing Wu, Chao Deng, Ying Gao

Journal of Electrochemistry

The polyaniline-carbon (PAnC) electrode was prepared by the polymerization of aniline monomer and activated carbon in ice water bath, and followed by chemical deposition of manganese dioxide MnO₂-PAnC composite material. The specific capacitance of MnO₂-PAnC reached 459 F•g^-1. The cyclic voltammetric results showed a small deformation in the voltammogram curve obtained with the MnO₂-PAnC electrode at high scan rate, indicating good reversibility and capacitive properties. The AC impedance results revealed that the MnO₂-PAnC electrode displayed the smallest charge transfer resistance and the fastest diffusion
rate of surface ions than other …

Examining The Bacterial Methionine Transporter Utilizing Soluble Lipid Bilayer Systems, Gabrielle Isabelle Servito, Michael Winslow, Dennis Hicks, Lyle Patrick Ureta

Creative Activity and Research Day - CARD

The phospholipid bilayer present in both eukaryotes and prokaryotes regulates the cell’s acquisition of nutrients and excretion of waste. Studies on the complex components of the lipid bilayer have paved the way for learning about the selective permeability of the membrane. It is of great interest to understand how materials are being transported through transmembrane proteins in relation to the electrochemical gradient. Investigation into the mechanistic properties of these transport proteins, particularly ATP-binding cassettes (ABC) transporters, can clarify how substrates are being transported via the binding and hydrolysis of adenosine triphosphate (ATP). The study of ABC transporters is significant in …

Practical Spectrophotometric Assay For The Dape-Encoded N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase, A Potential Antibiotic Target, Tahira K. Heath, Marlon R. Lutz Jr., Cory T. Reidl, Estefany R. Guzman, Claire A. Herbert, Boguslaw P. Nocek, Richard C. Hotz, Kenneth W. Olsen, Miguel A. Ballicora, Daniel P. Becker

Chemistry: Faculty Publications and Other Works

A new enzymatic assay for the bacterial enzyme succinyl-diaminopimelate desuccinylase (DapE, E.C. 3.5.1.18) is described. This assay employs N⁶-methyl-N²-succinyl-L,L-diaminopimelic acid (N⁶-methyl-L,L-SDAP) as the substrate with ninhydrin used to detect cleavage of the amide bond of the modified substrate, wherein N⁶-methylation enables selective detection of the primary amine enzymatic product. Molecular modeling supported preparation of the mono-N⁶-methylated-L,L-SDAP as an alternate substrate for the assay, given binding in the active site of DapE predicted to be comparable to the endogenous substrate. The alternate substrate for the assay, N^{6 …}

Synthesis And Characterization Of A Model Multi-Copper Oxidase, Joshua Gavin

Celebrating Scholarship and Creativity Day (2018-)

Multi-copper oxidases possess an unusual triangular copper complex; ceruloplasmin is an example. Ceruloplasmin oxidizes iron from the ferrous state to the ferric state, assisting in iron transport. This oxidn. is coupled with the redn. of dioxygen to water, the mechanism of which is unclear. In order to elucidate more the mechanism of redn., this study focuses on the synthesis and characterization of a novel copper (I) complex with a new tapma-based ligand. This tapma ligand is modeled after the tris (2-pyridylmethyl) amine-based (tpma) ligand family where nitrogen based donors are employed. This tapma ligand is synthesized from 1,3,5-tris(azidomethyl)-2,4,6-triethylbenzene in a …

Conformational Studies Of Gram-Negative Bacterial Quorum Sensing Acyl Homoserine Lactone (Ahl) Molecules: The Importance Of The N→* Interaction, Fintan Kelleher, Goar Sánchez-Sanz, Darren Crowe, Alan Nicholson, Adrienne Fleming

Articles

A ¹H NMR study shows the presence of intermolecular hydrogen bonds for AHLs in CDCl₃ solution. A detailed computational study of the structure of AHLs and the relative stability between the extended conformations (X) and those showing n→p* interactions (np) have been carried out by means of DFT calculations. Solvent effects have been shown to be very important when stabilising np conformations, particularly with polar solvents. This was shown by the shortening of C···O intramolecular distances and the increase in the relative energies favouring the np conformation with the dielectric constant of the solvent. …

Department Of Chemistry And Biochemistry 23rd Departmental Symposium In Conjunction With The Petersheim Academic Exposition, Seton Hall University

Petersheim Academic Exposition

No abstract provided.

Pharmaflights: Fragment Based Drug Discovery Based On Chalcones With A 3,4,5-Trimethoxy Substitution On Ring B., Cody Fourman

The University Honors Program

The 3,4,5-trimethoxyphenyl motif is a common structural feature of a number of natural occurring antimitotic agents, especially those capable interacting with microtubules such as the cis-stilbene, combrestatin A-4. Chalcones possessing this pharmacophore have likewise been demonstrated to exhibit a diverse range of biological actions including anticancer, anti-invasive, antioxidant, and anti-inflammatory activities. As part of an experiential learning experience in academic drug discovery termed WSU PharmaFlights, so-called flights of 6-10 molecules based on a particular biologically relevant structural pattern on the privileged chalcone scaffold are to be designed, synthesized, and spectroscopically characterized as a starting point for lead-development with potential biological …

Studies Aimed At The Synthesis Of Anti-Infective Agents, Ankush Kanwar

USF Tampa Graduate Theses and Dissertations

Infectious diseases continue to be a major concern worldwide. They are the second leading cause of death after heart disease. Factors such as an increasing global population, travel, urbanization, global climate change and evolution of pathogens have made infectious diseases more common. Infectious diseases, particularly neglected tropical diseases (NTDs) result in many deaths worldwide. Malaria and leishmaniasis are two common (NTDs) which affect low income countries around the globe. Low cost drugs with novel mechanism of action are required to tackle the growing resistances of parasites against current drugs used in the developing world, where most of the cases occur. …

Shaping Light In Backward-Wave Nonlinear Hyperbolic Metamaterials, Thomas George, Alexander Popov, Sergey Myslivets, Vitaly Slabko, Victor Tkachenko

Chemistry & Biochemistry Faculty Works

Backward electromagnetic waves are extraordinary waves with contra-directed phase velocity and energy flux. Unusual properties of the coherent nonlinear optical coupling of the phase-matched ordinary and backward electromagnetic waves with contra-directed energy fluxes are described that enable greatly-enhanced frequency and propagation direction conversion, parametrical amplification, as well as control of shape of the light pulses. Extraordinary transient processes that emerge in such metamaterials in pulsed regimes are described. The results of the numerical simulation of particular plasmonic metamaterials with hyperbolic dispersion are presented, which prove the possibility to match phases of such coupled guided ordinary and backward electromagnetic waves. Particular …

Synthesis Of Symmetric And Unsymmetric Secondary Amines From The Ligand-Promoted Ruthenium-Catalyzed Deaminative Coupling Reaction Of Primary Amines, Pandula T. Kirinde Arachchige, Hanbin Lee, Chae S. Yi

Chemistry Faculty Research and Publications

The catalytic system generated in situ from the tetranuclear Ru–H complex with a catechol ligand (1/L1) was found to be effective for the direct deaminative coupling of two primary amines to form secondary amines. The catalyst 1/L1 was highly chemoselective for promoting the coupling of two different primary amines to afford unsymmetric secondary amines. The analogous coupling of aniline with primary amines formed aryl-substituted secondary amines. The treatment of aniline-d₇ with 4-methoxybenzylamine led to the coupling product with significant deuterium incorporation on CH₂ (18% D). The most pronounced carbon isotope effect …

Cation Exchange Capacity Determination: Comparative Study Of Three Methods, Lillie Zech

Undergraduate Research Conference

No abstract provided.

Spidr: Small-Molecule Peptide-Influenced Drug Repurposing, Matthew D. King, Thomas Long, Daniel L. Pfalmer, Timothy L. Andersen, Owen M. Mcdougal

Chemistry and Biochemistry Faculty Publications and Presentations

Background: Conventional de novo drug design is costly and time consuming, making it accessible to only the best resourced research organizations. An emergent approach to new drug development is drug repurposing, in which compounds that have already gone through some level of clinical testing are examined for efficacy against diseases divergent than their original application. Repurposing of existing drugs circumvents the time and considerable cost of early stages of drug development, and can be accelerated by using software to screen existing chemical databases to identify suitable drug candidates.

Results: Small-molecule Peptide-Influenced Drug Repurposing (SPIDR) was developed to identify small molecule …

Bioinformatics- And Phylogenetics-Guided Approaches To Understanding Sequence-Function Relationships Of Type Ii Polyketide Biosynthetic Gene Clusters, Han Bich Nguyen

Chemistry and Chemical Biology ETDs

Type II polyketides (PK-II) has made up a class of natural products that are structurally diverse and are clinically useful due to their wide-range of bioactivity. The work described in this dissertation focuses on developing approaches to facilitate our understanding of sequence-function relationships of PK-II biosynthetic gene clusters (BGCs). We have systematically summarized the previous characterizations of enzymes involved in the core structure biosynthesis, which have set a foundation for our developments of approaches to discover organisms harboring novel enzymes responsible for novel PK-II molecules. We have successfully developed bioinformatics tools to globally mine the PK-II BGCs in the NCBI …

Steric Effects On The Formation Of Manganese Oxide Clusters And 2-Dimensional Ammonium Formate Architectures, Carl Oberle

Dissertations

It has been demonstrated by the Beatty group that altering the identity of the ortho-substituent of a dianiline counterion affects the assembly and dimensionality of a cadmium-chloride layer from 2-D to 0-D. This work seeks to extend this finding to metal oxide and organic hydrogen-bonded materials. By systematically increasing the ortho­-substituent’s size on the benzoate building block of reported manganese oxide clusters, of formula Mn_xO_y(O₂C-R)_zL_w (where R = Alkyl, L = neutral monodentate ligand), we aim to impact the self-assembly of these materials relative to their parent …

Chloroform Extracts Of Ipomoea Alba And Ipomoea Tricolor Seeds Show Strong In-Vitro Antibacterial, Antifungal, And Cytotoxic Activity, Sims K. Lawson, Mary N. Davis, Carolyn Brazell

Research Horizons Day Posters

No abstract provided.

Evaluation Of Vaporization Enthalpies And Vapor Pressures Of Various Aroma And Pharmacologically Active Compounds By Correlation Gas Chromatography, Daniel Simmons

Theses

Scientists in the pharmaceutical, food, and aroma industries can benefit from reliable thermochemical data. Vaporization enthalpy and vapor pressure data are not available for all compounds. Furthermore, some literature data is conflicting. The goal of this work was to use a method called correlation gas chromatography (CGC) to generate reliable vaporization enthalpy data in instances where other experimental methods are not applicable. Vapor pressures of the targets were also calculated in cases where the required literature data on the standards used in this technique were available.

CGC involves making a standard cocktail that includes a mixture of standards and one …

From Flasks To Applications: Design And Optimization Of Giant Quantum Dots Using Traditional And Automated Synthetic Methods, Christina J. Hanson

Nanoscience and Microsystems ETDs

Semiconducting nanocrystals, also known as quantum dots (QDs), that emit light with near-unity quantum yield and are extremely photostable are attractive options as down-conversion and direct electricity-to-light materials for a variety of applications including solid-state lighting, display technologies, bio-imaging and optical tracking. Standard QDs with a core/thin shell structure display fluorescence intermittency (blinking) and photobleaching when exposed to prolonged room temperature excitation for single dot measurements, as well as significant reabsorption and energy transfer when densely packed into polymers or at high solution concentrations.

We have developed thick shell “giant” QDs (gQDs), ultra-stable photon sources both at the ensemble and …

Structural Evidence For Rifampicin Monooxygenase Inactivating Rifampicin By Cleaving Its Ansa-Bridge, Li Kai Liu, Yumin Dai, Heba Abdelwahab, Pablo Sobrado, John J. Tanner

Chemistry Faculty Research & Creative Works

Rifampicin monooxygenase (RIFMO) decreases the potency of rifampicin (RIF) by converting it to oxidative products. Further decomposition of RIF has been observed in bacteria producing RIFMO and contributes to RIFMO-mediated drug resistance. Here we report the first crystal structure of RIFMO in complex with the hydroxylated RIF product. The 2.10 Å resolution structure reveals a breach of the ansa aliphatic chain of RIF between naphthoquinone C2 and amide N1. Our data suggest that RIFMO catalyzes the hydroxylation of RIF at the C2 atom followed by cleavage of the ansa linkage, which leads to inactivation of the antibiotic by preventing key …

Synthesis Of Oxygenated Boronic Acid Substituted A-Cyanostilbenes For Use As Antibacterial, Yewon Kim

Honors Theses

Stilbenes are naturally occurring compounds that have exhibited antibacterial activity, although the biological effect of various stilbenes differs for Gram-positive and Gram-negative strains of bacteria. In prior research, cyanostilbenes have shown slight antibacterial activity (Brownlee, et al. 1943). This project aims to explore whether hybrid oxygenated a-cyanostilbenes possessing a boronic acid pharmacophore exhibits significant antibacterial activity (Das et al. 2013). The biological activity against Staphylocococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) was tested using the Kirby-Bauer text. No inhibition of E. coli growth was shown while S. aureus was partially inhibited.

Evaluating Mutagenicity Of Burned Arginine-Based Heterocyclic Amines And Anti-Mutagenicity Effect Of Chinese Medicinal Herbs, Rayford C. Alva

Honors Theses

From the unexpected finding that cooked grains and meat substitutes elicit a mutagenic response in Salmonella typhimurium TA98, our work has been aimed at deconstructing this finding via a survey of heated binary amino acid combinations, involving arginine, a plant-based amino acid. secondly, our work has looked towards sing phytochemical extracts from traditional Chinese medicinal herbs to inhibit the mutagenic activity of heterocyclic amines (main culprit for mutagenicity in meat). Two fractions from the burned products of arginine and phenylalanine (RF-HCA-06 and -07) were statistically significant inducers of mutagenesis; Scutellaria barbata and Oldenlandia diffusa, both separately and together, were statistically …

From Florida To Antarctica: Dereplication Strategies And Chemical Investigations Of Marine Organisms, Matthew A. Knestrick

USF Tampa Graduate Theses and Dissertations

In the fight against disease and illness, nature has provided mankind some of our best therapeutics in the form of secondary metabolites. The plant, fungi and animal phyla inhabiting the Earth produce diverse and unique chemistry that can be used in our fight against disease. In the growing threat of drug resistance and pathogen evolution, the field of natural products chemistry strives to explore new biological and chemical diversity sources, and develop innovative methodology to identify and isolate new chemistry faster than ever.

The dissertation herein presented is one such effort to find new, bioactive chemistry from the marine environments. …

Temporal Changes In Dissolved Calcium In Stream And River Waters In Western Kentucky Watershed, Adam Martin

Scholars Week

Temporal Changes in Dissolved Calcium in Stream and River Waters in Western Kentucky Watershed

Effect Of Electron Withdrawing And Electron Donating Substituents On The Synthesis Of 1,3,4-Oxadiazoles Using Dibromotriphenylphosphorane, Emily Bliss

Undergraduate Distinction Papers

The goal of this project was to determine the effects that electron withdrawing and electron donating substituents have on the synthesis of 1,3,4-oxadiazoles using a hydrazide starting material and dibromotriphenylphosphorane. This investigation involved the synthesis of hydrazide starting material followed by the synthesis of the oxadiazole with electron donating, withdrawing, or neutral substituents. Through this study, one neutral, three electron donating, two electron withdrawing substituents were investigated. Reactions were analyzed through nuclear magnetic resonance spectroscopy. Neutral electronegative substituents were deemed to be more successful through their percent yield and nuclear magnetic resonance spectroscopy data than both electron donating and withdrawing …

Workflows For X-Ray And Neutron Interferometry/Tomography As Applied To Additive Manufacturing, Jumao Yuan

LSU Doctoral Dissertations

Grating-based interferometry/tomography is being rapidly developed for non-destructive evaluation of additive manufacturing test articles. An application requiring an efficient workflow is extremely necessary for stress and fatigue testing samples.

At present, scientific workflows play an important role for computational experiments in additive manufacturing 3D printing and interferometry/tomography imaging analysis. A clear workflow template allows scientists to process experiments easier and faster. Work flow library grows, but to find an appropriate workflow for their task is challenging. In our research, there are mainly three portions in the workflow, interferometry analysis, image reconstruction and 3D visualization. Currently, the hierarchy of workflows in …

Epoxy Phosphonate Ester As A Coupling Agent For Transition Metal And Metal Oxide Surfaces, Thomas P. Schuman

Chemistry Faculty Research & Creative Works

A method for surface modification of a substrate comprising surface oxide and/or hydroxy groups, with a compound comprising an ester group and an epoxy ring, wherein the epoxy group remains intact after the reacting. A method for surface modification of a substrate comprising surface oxide and/or hydroxy groups, with a compound comprising an ester group and a functionalized epoxy ring, wherein the functionalized epoxy group remains intact after the reacting. A composite material comprising surface-modified metal oxide nanoparticles dispersed within a polymeric material, wherein the surface modification comprises a compound comprising an ester group and an epoxy ring is also …

Elemental Analysis Of Beer Manufactured In Virginia Satellite Breweries, Jennifer Wiliams

Student Scholar Showcase

Financial incentives from the state and wider distribution potential have lured many west coast brewers to open satellite breweries in Virginia. Quality control is crucial for any brewery and especially important in satellite breweries that need to imitate the standard set by the parent brewery. Zinc, magnesium, iron, sodium manganese, and calcium are trace elements found in wort and are essential for enzymes that catalyze fermentation reactions. These elements protect against cell stress, play a crucial role in flocculation, and can affect the flavoring and coloration of beer. Barley, water, and hops are the sources of these elements in beer. …

Elastin-Like Polypeptide Fusion Tag As A Protein-Dependent Solubility Enhancer Of Cysteine-Knot Growth Factors, Tamina L. Johnson

USF Tampa Graduate Theses and Dissertations

Elastin-like peptide (ELP) fusions promote therapeutic delivery and efficacy. Recombinant proteins, like neurotrophins, lack bioavailability, have short in vivo half-lives, and require high manufacturing costs. Fusing recombinant proteins with genetically encodable ELPs will increase bioavailability, enhance in vivo solubilization, as well as provide a cost-effective method for purification without the need for chromatography. During expression of neurotrophin-ELP (N-ELP) fusions, dense water-insoluble aggregates known as inclusion bodies (IBs) are formed. Inclusion bodies are partially and misfolded proteins that usually require denaturants like Urea for solubilization. Strong denaturants arrest ELPs stimuli-responsive property and increase unwanted aggregation, making purification difficult, yet possible. The …