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Synthesis And Spectroscopic Characterization Of High-Spin Mononuclear Iron(Ii) P-Semiquinonate Complexes, Amanda E. Baum, Heaweon Park, Sergey V. Lindeman, Adam T. Fiedler

Chemistry Faculty Research and Publications

Two mononuclear iron(II) p-semiquinonate (pSQ) complexes have been generated via one-electron reduction of precursor complexes containing a substituted 1,4-naphthoquinone ligand. Detailed spectroscopic and computational analysis confirmed the presence of a coordinated pSQ radical ferromagnetically coupled to the high-spin FeII center. The complexes are intended to model electronic interactions between (semi)quinone and iron cofactors in biology.

Aerogels As Diverse Nanomaterials, Abhishek N. Bang

Doctoral Dissertations

"Aerogels are 3-D light-weight nanoporous materials pursued for their low thermal conductivity, low dielectric constant and high acoustic attenuation. Those exceptional macroscopic properties of aerogels are dependent on the chemical nature of nanoparticles, complex hierarchical solid skeletal framework and porosity. Also, the free space can become host for functional guests such as pharmaceuticals. In chapter I, we investigated randomly mesoporous bio-compatible polymer-crosslinked dysprosia aerogels as drug delivery vehicles and demonstrated storage and release of drugs under physiological conditions. Comparative study with ordered and randomly mesoporous silica showed high drug uptake and slower release rate for random nanostructures (silica or dysprosia) …

Synthesis Of Novel C-4 Disubstituted Β-Lactams Through Staudinger Cycloaddition Reaction, Robert Rodriguez, Anjali Nambiar, Ram N. Yadav, Bimal K. Banik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Synthesis of novel C-4 disubstituted beta-lactam that has N-methyl pyrrole system has been achieved through Staudinger cycloaddition reaction of acid chloride and imine. Interestingly, this reaction has produced a single stereoisomer.

Investigating The Biochemical And Catalytic Properties Of Nitrile Hydratases, Salette Martinez

Dissertations

Chemical and pharmaceutical industries make extensive use of amide compounds for the manufacture of commodity chemicals (e.g., acrylamide) and drug intermediates (e.g., nicotinamide). Production of amide compounds is typically achieved by the hydration of nitrile compounds under acidic or basic conditions, high temperatures, and copper catalysts. However, the use of such chemical methods leads to the generation of unwanted by-products and toxic wastes, in addition to low product yields and high production costs. An alternative route for amide production is the use of a natural catalyst, for example nitrile hydratases (NHase, E.C. 4.2.1.84). NHase is a metalloenzyme that efficiently converts …

On Readout Of Vibrational Qubits Using Quantum Beats, Dmytro Shyshlov, Eduardo Berrios, Martin Gruebele, Dmitri Babikov

Chemistry Faculty Research and Publications

Readout of the final states of qubits is a crucial step towards implementing quantum computation in experiment. Although not scalable to large numbers of qubits per molecule, computational studies show that molecular vibrations could provide a significant (factor 2–5 in the literature) increase in the number of qubits compared to two-level systems. In this theoretical work, we explore the process of readout from vibrational qubits in thiophosgene molecule, SCCl₂, using quantum beat oscillations. The quantum beats are measured by first exciting the superposition of the qubit-encoding vibrational states to the electronically excited readout state with variable time-delay pulses. …

Investigations Into The Fluorescent Covalent Labeling Of Biomolecules Utilizing Rhodamine Dyes, Electrophilic Leaving Groups And Mrna Display., Susan D. Selaya

Theses and Dissertations

The discovery of a method by which proteins of interest can selectively be labeled with a probe of choice intracellularly is a longstanding goal in chemical biology research. Conventional labeling techniques have utilized large domain tags but despite the development of small labeling molecules there have been no short peptide sequences known to covalently label a small molecule without the aid of an enzymatic process or metal chelation. We aimed to find a sequence of nucleophilic peptides that reacted covalently and specifically with electrophilic small labeling molecules using mRNA display. Our goal was to show that an electrophilic small labeling …

Platinum Complexes And Zinc Finger Proteins: From Target Recognition To Fixation, Samantha Tsotsoros

Theses and Dissertations

Bioinorganic chemistry strives to understand the roles of metals in biological systems, whether in the form of naturally occurring or addition of non-essential metals to natural systems. Metal ions play vital roles in many cellular functions such as gene expression/regulation and DNA transcription and repair. The study of metal-protein-DNA/RNA interactions has been relatively unexplored. It is important to understand the role of metalloprotein interactions with DNA/RNA as this enhanced knowledge may lead to better understanding of diseases and therefore more effective treatments. A major milestone in the development of this field was the discovery of the cytotoxic properties of cisplatin …

Concern-Driven Integrated Toxicity Testing Strategies For Nanomaterials - Report Of The Nanosafety Cluster Working Group 10, Hugh Byrne, Agnes G. Oomen, Peter M.J. Bos, Teresa F. Fernandes, Kerstin Hund-Rinke, Diana Boraschi, Karin Aschberger, Stefania Gottardo, Frank Von Der Kammer, Dana Kühnel, Danail Hristozov, Antonio Marcomini, Lucia Migliore

Articles

Bringing together topic-related European Union-(EU)-funded projects, the so-called “NanoSafety Cluster” aims at identifying key areas for further research on risk assessment procedures for nanomaterials (NM). The outcome of NanoSafety Cluster Working Group 10, this commentary presents a vision for concern-driven integrated approaches for the (eco-)toxicological testing and assessment (IATA) of NM. Such approaches should start out by determining concerns, i.e. specific information needs for a given NM based on realistic exposure scenarios. Recognized concerns can be addressed in a set of tiers using standardized protocols for NM preparation and testing. Tier 1 includes determining physico-chemical properties, non-testing (e.g. structure …

Visible Light Mediated Intermolecular [3 + 2] Annulation Of Cyclopropylanilines With Alkynes, Theresa H. Nguyen, Soumitra Maity, Nan Zheng

Chemistry & Biochemistry Faculty Publications and Presentations

Intermolecular [3 + 2] annulation of cyclopropylanilines with alkynes is realized using visible light photoredox catalysis, yielding a variety of cyclic allylic amines in fair to good yields. This method exhibits significant group tolerance particularly with heterocycles. It can also be used to prepare complex heterocycles such as fused indolines.

Longitudinal Plasmonic Detection Of Glucose Using Gold Nanorods, Ching An Peng, Sushil Pachpinde

Michigan Tech Publications, Part 1

Gold nanorod-based affinity sensors were developed utilizing concanavalin-A/dextran/glucose chemistry to detect glucose. The gold nanorods, synthesized using the seed-mediated method, were first coated with dextran sulfate. The dextran sulfate coating changed the local refractive index, which was observed as a red shift in the longitudinal plasmon band. After the addition of 8 μM concanavalin-A, gold nanorod aggregates were formed as shown by TEM analysis. The corresponding UV-Vis spectrum peak wavelength showed a red shift from 701 nm of dextran sulfate coated gold nanorods to 718 nm of concanavalin-A promoted gold nanorod aggregates. The gold nanorod aggregates were dissociated when 12 …

Basic Features Of A Cell Electroporation Model: Illustrative Behavior For Two Very Different Pulses, Reuben S. Son, Kyle C. Smith, Thiruvallur R. Gowrishankar, P. Thomas Vernier, James C. Weaver

Bioelectrics Publications

Science increasingly involves complex modeling. Here we describe a model for cell electroporation in which membrane properties are dynamically modified by poration. Spatial scales range from cell membrane thickness (5 nm) to a typical mammalian cell radius (10 μm), and can be used with idealized and experimental pulse waveforms. The model consists of traditional passive components and additional active components representing nonequilibrium processes. Model responses include measurable quantities: transmembrane voltage, membrane electrical conductance, and solute transport rates and amounts for the representative "long" and "short" pulses. The long pulse-1.5 kV/cm, 100 μs-evolves two pore subpopulations with a valley at ~5 …

Advances In Understanding The Molecular Composition Of Dissolved Organic Matter And Its Reactivity In The Environment, Rajaa Mesfioui

Chemistry & Biochemistry Theses & Dissertations

Dissolved organic matter (DOM) is the ultimate product of Earth's systems dynamics. DOM chemical signature is strongly shaped by the interaction among Earth's spheres, such as the atmosphere, the geosphere, the biosphere, and the hydrosphere, but also life and human activity. DOM source, composition, photochemical alteration and availability affect freshwater ecosystems, their carbon and nitrogen fluxes and, thus, the global carbon and nitrogen cycles. The aim of this thesis was to gain an understanding of the molecular composition of DOM and its photochemical and biological reactivity in an environment impacted by anthropogenic disturbance. The York and James River systems within …

Spectroscopic Characterization Of Dissolved Organic Matter: Insights Into The Linkage Between Sources And Chemical Composition, Xiaoyan Cao

Chemistry & Biochemistry Theses & Dissertations

This dissertation investigated the chemical structure of DOM by advanced solid-state nuclear magnetic resonance (NMR) spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) techniques, as well as isotopic measurements and UV-visible spectroscopy, to shed light on the linkages between DOM sources and DOM composition. Unique and extensive sets of DOM samples studied here were isolated from various aquatic systems, covering end-member environments in which DOM is considered either microbially derived or terrestrially derived, and areas in which DOM has characteristics intermediate between the two end members. Important insights into specific site-related questions were also gained such as …

Isomerase Activity Of Candida Rugosa Lipase In Conversion Of Racemic Ibuprofen To (S)-Ibuprofen, Saideh Sadat Mortazavi

Open Access Theses & Dissertations

The Candida rugosa lipase-catalyzed Dynamic Kinetic Resolution of racemic ibuprofen methyl ester was optimal at pH 7.6 to produce (S)-ibuprofen in 72 hours. The concentration of various buffers for these reactions ranged from 0.2 to 0.5 M. The commercial lipase was found to be acidic altering the final pH of the reaction mixtures. Dimethylformamide co-solvent maintained the reaction pH better than dimethylsulfoxide, with evidence of the latter functioning as an oxidizing agent. Lower concentrations of ibuprofen methyl ester and higher stirring rates led to faster conversions. The minimal amount of lipase needed was 20 mg/mL buffer. Reaction of (R)-ibuprofen methyl …

Environmental Assessment Of Used Motor Oil In The Ciudad Juarez-El Paso Area, Alma Leticia Figueroa

Open Access Theses & Dissertations

As a hazardous waste generated in large amounts worldwide, used motor oil (UMO) is an important issue for environmental science. UMO contains the carcinogenic and mutagenic compounds Polycyclic Aromatic Hydrocarbons (PAHs). Unless properly managed and disposed of PAHs remain in the environment, principally in sediments and soil. From such environmental sinks, PAHs can migrate to watersheds contaminate drinking water, and damage ecosystems and human health.

Generators of used oil include "businesses that handle used oil through commercial or industrial operations or from the maintenance of vehicles and equipment," (United States Environmental Protection Agency (USEPA), 2013). An example of such a …

Structural Investigation Of The Molecular Chaperonin Tf55 From Thermophilic Archaeon Sulfolobus Solfataricus, Sanjay Kumar Molugu

Open Access Theses & Dissertations

Chaperonins are ubiquitous multi-subunit macromolecules that mediate the folding and assembly of certain proteins that cannot fold properly in vivo. The Archaea bacterium Sulfolobus solfataricus encodes for three chaperonin complexes formed from three different, but closely related subunits named alpha,betaand Gamma. These subunits form a homo-18mer composed of all beta subunits at temperatures ranging between 80oC-85oC, a hetero-16mer composed of alpha and beta subunits at temperatures ranging between 70oC-75oC and a hetero 18mer composed of alpha, beta and gamma subunits at temperatures of 60oC. Structures exist for the chaperonin TF55 all-beta complex and for the TF55 alpha-beta complex but not …

Synthesis Of Peptide-Α-Phenylthioesters Using A Solid Support With A Photoreactive Nitroindoline Moiety, Andrew Pardo

Open Access Theses & Dissertations

Peptide-alpha-phenylthioesters are particularly reactive starting materials for Native Chemical Ligation. Here we present a new photochemical method for the synThesis of peptide-alpha-phenylthioesters under neutral reaction conditions with various C-terminal amino acids. The peptides were synthesized by Fmoc strategy on Sieber amide resin with a photoreactive nitroindoline linker. After cleavage of the photoreactive and fully protected peptide from the beads with dilute trifluoroacetic acid an auxiliary nucleophile such as N-hydroxybenzotriazole or N-hydroxysuccinimide is used to photochemically generate the activated peptide ester in situ. Then thiophenol is introduced in the dark. This new method enabled us to synthesize peptide-alpha-phenylthioesters up to 21 …

Effects Of Cerium Oxide Nanoparticles In Cereals: Insights Into The Toxicity Mechanisms And Macromolecular Modifications, Cyren Mendoza Rico

Open Access Theses & Dissertations

Despite the inundation of studies on the interaction of engineered nanomaterials (ENMs) with plants, investigations involving complete life cycle (i.e from seedling establishment to full maturity) are still lacking. Assessments on the nutritional value of plants cultivated to full maturity in ENMs-treated soil are also missing. Cerium oxide nanoparticles (nCeO2) have significant interactions with plants; however, there are no life cycle studies yet on their implications in cereals like rice (Oryza sativa L.), wheat (Triticum aestivum L.), and barley (Hordeum vulgare L.). These cereals are globally important crops that support the economic activity, and nutritional and health needs of billions …

Microwave-Assisted Synthesis Of Carbon Supported Metal/Metal Oxide Nanocomposites And Their Application In Water Purification, Gunawan Gunawan

Theses and Dissertations

A novel, easy, and cost effective method for synthesizing carbon supported metal/metal oxide nanocomposites has been studied. Carbon supported metal/metal oxide nanocomposites have niche applications in the area of catalysis, fuel cells, electrodes, and more. The method utilizes a commercial microwave and features the addition of a developed graphite-jacket technique with renewable carbon resources, tannin and lignin. The method has been successfully used to synthesize carbon/nickel, carbon/iron oxide, and carbon/nickel phosphide nanocomposites. The method has shown its versatility in the synthesis of carbon nanocomposites. The process is much simpler when compared with the available methods for synthesizing carbon nanocomposites. The …

Infrared Vibrational Spectroscopy Analysis Of Selected Biomolecules, Busra Ergul

Theses and Dissertations

Fourier transform infrared (FTIR) spectroscopy is a useful tool to examine biological molecules for noninvasive measurements. This research has focused on the determination of concentrations of four important biomolecules, glucose, gluconic acid, hydrogen peroxide (H2O2), and dopamine by FTIR. It is crucial to determine blood glucose levels for diabetes diagnosis. H2O2 is an important biomolecule having implications in aging and aging related diseases. Gluconic acid is important in food and pharmaceutical industries, and dopamine plays a key role in brain activity. In this work, first, glucose, gluconic acid, and H2O2 in aqueous solutions have been studied by using FTIR. Standard …

Nicotine Exploits A Copi-Mediated Process For Chaperone-Mediated Up-Regulation Of Its Receptors, Brandon J. Henderson, Rahul Srinivasan, Weston A. Nichols, Crystal N. Dilworth, Diana F. Gutierrez, Elisha D. W. Mackey, Sheri Mckinney, Ryan M. Drenan, Christopher I. Richards, Henry A. Lester

Chemistry Faculty Publications

Chronic exposure to nicotine up-regulates high sensitivity nicotinic acetylcholine receptors (nAChRs) in the brain. This up-regulation partially underlies addiction and may also contribute to protection against Parkinson's disease. nAChRs containing the α6 subunit (α6* nAChRs) are expressed in neurons in several brain regions, but comparatively little is known about the effect of chronic nicotine on these nAChRs. We report here that nicotine up-regulates α6* nAChRs in several mouse brain regions (substantia nigra pars compacta, ventral tegmental area, medial habenula, and superior colliculus) and in neuroblastoma 2a cells. We present evidence that a coat protein complex I (COPI)-mediated process mediates this …

Amino Acid Region 1000–1008 Of Factor V Is A Dynamic Regulator For The Emergence Of Procoagulant Activity, Joesph R. Wiencek, Mahesheema Na, Jamila Hirbawi, Michael Kalafatis

Chemistry Faculty Publications

Single chain factor V (fV) circulates as an Mr 330,000 quiescent pro-cofactor. Removal of the B domain and generation of factor Va (fVa) are vital for procoagulant activity. We investigated the role of the basic amino acid region 1000-1008 within the B domain of fV by constructing a recombinant mutant fV molecule with all activation cleavage sites (Arg(709)/Arg(1018)/Arg(1545)) mutated to glutamine (fV(Q3)), a mutant fV molecule with region 1000-1008 deleted (fV(ΔB9)), and a mutant fV molecule containing the same deletion with activation cleavage sites changed to glutamine (fV(ΔB9/Q3)). The recombinant molecules along with wild type fV (fV(WT)) were transiently expressed …

Table Of Contents, Michele Harmon

Journal of the South Carolina Academy of Science

No abstract provided.

High Yield Solvothermal Synthesis Of Hexaniobate Based Nanocomposites Via The Capture Of Preformed Nanoparticles In Scrolled Nanosheets, Shivaprasad Reddy Adireddy

LSU New Orleans Theses and Dissertations

The ability to encapsulate linear nanoparticle (NP) chains in scrolled nanosheets is an important advance in the formation of nanocomposites.These nanopeapods (NPPs) exhibit interesting properties that may not be achieved by individual entities. Consequently, to fully exploit the potential of NPPs, the fabrication of NPPs must focus on producing composites with unique combinations of morphologically uniform nanomaterials. Various methods can produce NPPs, but expanding these methods to a wide variety of material combinations can be difficult. Recent work in our group has resulted in the in situ formation of peapod-like structures based on chains of cobalt NPs. Building on this …

High Resolution X-Ray Diffraction Analysis Of Cb1 Receptor Antagonists As A Means To Explore Binding Affinity, Steven P. Fournet

LSU New Orleans Theses and Dissertations

Abstract

Charge density studies have been conducted on ten CB₁ cannabinoid receptor antagonists via high resolution x-ray crystallography. Bond critical point values and various other properties derived from these studies including the electrostatic potential were analyzed in correlation to the affinity of each compound with the CB₁ receptor. Correlation/anti-correlation was found between several properties and K_i. The data was also interpreted by principal component analysis with three principal components accounting for 85% of the data variation. Data mining was limit due to the low sample count and the requirements set for the inclusion of correlated/anti-correlated variables …

Synthesis Of Novel Azetidines, Amber Thaxton

LSU New Orleans Theses and Dissertations

Azetidine is a four-membered nitrogen-containing heterocyclic ring that has recently received a great deal of attention as a molecular scaffold for the design and preparation of biologically active compounds. Structure-activity studies employing functionalized azetidines have led to the development of variety of drug molecules and clinical candidates encompassing a broad spectrum of biological activities.

Herein, the synthesis a novel series of 3-aryl-3-arylmethoxyazetidines is described. Selected 3-aryl-3-arylmethoxyazetidines were evaluated for their binding affinity to multiple monoaminergic transporters for the potential treatment of methamphetamine addiction. It was discovered that this scaffold exhibits high binding affinity (nM) for both the serotonin and dopamine …

Dose Dependent Effects Of Caffeine On Cognitive Performance And Neuronal Activation, Stephan Albrecht, Helen Morris, Michelle Vieyra

Journal of the South Carolina Academy of Science

Many students assume that the more caffeine you drink, the better your cognitive performance. Over-consumption of caffeine has many negative effects, so if there are no dose related cognitive benefits to large amounts of caffeine, then college students should limit their intake. This study looked at whether ingesting a medium dose (200 mg) versus a lower dose (100 mg) of caffeine improved short term memory as measured by Flanker and n-back tests, compared to a control group. In addition, we looked at whether larger doses of caffeine produced a difference in neuronal activation during these tests as measured by functional …

Fourier Analysis Of Phase Resetting Curves Of Neural Oscillators, Robert A. Raidt, Sorinel A. Oprisan

Journal of the South Carolina Academy of Science

We investigated the impact of changes in biologically relevant control parameters, such as the shape of an external perturbation or the conductance values of an individual model neuron, on the shape of the phase resetting curve (PRC) of that neuron. For that purpose, PRCs were generated for groups of Morris-Lecar (ML) model neurons with different conductance values but similar firing periods (within 0.005ms) using external rectangular, triangular, or trapezoidal perturbations of varying areas. These PRCs were numerically described and analyzed as a series of coefficient values using a Fourier Discrete Sine Transform (DST). We found that changes in the shape …

Nmr Determination Of Enantiomeric Composition Of Chiral Alcohols Using Camphorsulfonate Esters, Steven Bondi Fcrh '11, Thomas Lobasso Fcrh '09, Christa Iwanoski Fcrh '09, Shahrokh Saba, Donald Clarke

The Fordham Undergraduate Research Journal

Most biologically active compounds, including pharmaceuticals, have chiral molecular structures. With increased recognition that enantiomers of chiral drugs are metabolized differently, there has been enormous interest in the development of enantioselective methodologies for the synthesis of chiral compounds. NMR spectroscopy has emerged as a powerful method for discrimination of enantiomers of chiral compounds. 1 One strategy by which the NMR method is exploited is based on converting the enantiomers of a chiral compound to diastereomers using a chiral derivatizing agent. These diastereomers often display anisochronous NMR signals, which can be identified and integrated affording quantitative measurements of the optical purity …

The Spontaneous Formation Of Selenium Nanoparticles On Gallic Acid Assemblies And Their Antioxidant Properties, Stacey Barnaby Fcrh '11, Nazmul Sarker Fcrh '13, Aaron Dowdell Fcrh '12, Ipsita Bannerjee

The Fordham Undergraduate Research Journal

Gallic acid (GA) is a naturally occurring plant phenol known for its anti-inflammatory and antioxidant properties. In this work, we probed the molecular self-assembly of GA for the development of GA based nanocomposites for potential device fabrications and enhanced antioxidant applications. We found that the formation of GA nanostructures was pH dependent. Further, we examined the interactions of selenite with GA and subsequently examined the biomimetic formation of selenium (Se) nanoparticles. We found that in the presence of selenite, the yield of nanofibers was significantly higher, and selenium nanoparticle coated nanofibers were formed. The ability of the nanocomposites to scavenge …