Chemistry Commons^™

Application Of An Ionic Liquid Column To The Analysis Of Flavor And Fragrance Ingredients, Nicole L. Curto

Seton Hall University Dissertations and Theses (ETDs)

Traditional, polar (polyethylene glycol/wax) stationary phase gas chromatography columns pose challenges for flavor and fragrance analysis particularly in regards to thermal instability at high temperatures, degradation when exposed to water, unchanging selectivity, and relatively short shelf lives. Recently, capillary columns using ionic liquids as stationary phases have become available. Ionic liquid columns offer a potential combination of high polarity and high temperature stability with unique selectivity. An in depth discussion about the history and development of column phase characterization, with specific emphasis on selectivity and polarity, will allow for a critical look at the polarity scale currently employed to characterize …

Structural Analysis Of Transient Receptor Potential Vanilloid Type 1 (Trpv1) Channel Protein And Proline Mimics Using Computational Techniques, Kelly A. Raymond

Seton Hall University Dissertations and Theses (ETDs)

Chapter I

The Transient Receptor Potential (TRP) family of ion channels encompasses more than 30 members, which are expressed in many different tissues and cell types.¹ Transient Receptor Potential Vanilloid Type 1 (TRPV1) is part of the TRP family gated by vanilloids, heat and protons.² Molecular modeling will be used in order obtain structural and functional data on TRPV1 in its membrane bound environment. In particular, the transmembrane and C-terminal domain regions of TRPV1 are of particular interest. The S1-S4 region of the channel is the putative ligand-binding segment, while the C-terminal domain is suggested to respond to …

Functionalization Of Metal Oxide Surfaces Through Chemical Reactions And Physical Adsorption, Gabriel C. Graffius

Seton Hall University Dissertations and Theses (ETDs)

The synthesis of high surface area metal oxides is an area of extensive research with potential applications in catalysis, adsorption, and materials chemistry. The functionalization of a material’s surface can dramatically change its physical and chemical properties. The research described herein is built on the foundation of traditional techniques used for synthesis, characterization, and functionalization of metal oxides and develops new mechanisms and materials for the functionalization of surfaces.

We began with Methyl-terminated poly(dimethylsiloxanes) (PDMSs), which are typically considered to be inert and not suitable for surface functionalization reactions because of the absence of readily hydrolysable groups. Nevertheless, these siloxanes …

Synthesis And Evaluation Of Biological Activity Of A Potential Immunomodulatory Zwitterionic Polysaccharide, Vikram Basava

Seton Hall University Dissertations and Theses (ETDs)

The gram-negative anaerobic bacterium Bacteroides fragilis is an integral component of the normal gastrointestinal flora. The bacterium colonizes the intestinal tract of human beings as it has no reservoir other than mammals. An unprecedented proportion of the genomic DNA of B. fragilus is involved in the production of capsular polysaccharides. These capsular polysaccharides are important virulence factors in most extracellular bacterial pathogens. Eight of these polysaccharides have been identified thus far, out of which two were found to be zwitterionic polymers, PSA1 and PSA2. PSA1 was found to stimulate T-cell lineage of the immune system because of the dual charge …

Synthesis And Topochemical Manipulation Of New Layered Perovskites, Lea Gustin

LSU New Orleans Theses and Dissertations

Metastable layered perovskites containing interlayer transition metals can readily be obtained by simple ion exchange reactions on receptive hosts, such as those of the Dion-Jacobson and Ruddlesden-Popper structure types. In this work, we focused on adding to the library of layered perovskites by not only creating new compounds, but by also showing their ability to be further manipulated, and by studying the stability of the series through thermal behavior studies.

The reactions with transition metal halides are particularly interesting since they often lead to novel architectures and magnetic behavior. On subsequent heat treatment, these exchange products typically decompose to thermodynamically …

Indacenodibenzothiophenes: Synthesis, Optoelectronic Properties And Materials Applications Of Molecules With Strong Antiaromatic Character, Jonathan L. Marshall, Kazuyuki Uchida, Conerd K. Frederickson, Christian Schütt, Andrew M. Zeidell, Katelyn P. Goetz, Tristan W. Finn, Karol Jarolimek, Lev N. Zakharov, Chad Risko, Rainer Herges, Oana D. Jurchescu, Michael M. Haley

Chemistry Faculty Publications

Indeno[1,2-b]fluorenes (IFs), while containing 4n π-electrons, are best described as two aromatic benzene rings fused to a weakly paratropic s-indacene core. In this study, we find that replacement of the outer benzene rings of an IF with benzothiophenes allows the antiaromaticity of the central s-indacene to strongly reassert itself. Herein we report a combined synthetic, computational, structural, and materials study of anti- and syn-indacenodibenzothiophenes (IDBTs). We have developed an efficient and scalable synthesis for preparation of a series of aryl- and ethynyl-substituted IDBTs. NICS-XY scans and ACID calculations reveal an increasingly antiaromatic core from …

2016-01-A3dsrinp-Csc-Sta-Cmb-522-Bps-542, Raymond Pulver, Neal Buxton, Xiaodong Wang, John Lucci, Jean Yves Hervé, Lenore Martin

Bioinformatics Software Design Projects

Cholesterol is carried and transported through bloodstream by lipoproteins. There are two types of lipoproteins: low density lipoprotein, or LDL, and high density lipoprotein, or HDL. LDL cholesterol is considered “bad” cholesterol because it can form plaque and hard deposit leading to arteries clog and make them less flexible. Heart attack or stroke will happen if the hard deposit blocks a narrowed artery. HDL cholesterol helps to remove LDL from the artery back to the liver.

Traditionally, particle counts of LDL and HDL plays an important role to understanding and prediction of heart disease risk. But recently research suggested that …

A New 2,1,3-Benzothiadiazole-Fused N-Heterocyclic Carbene And Its Metal Complexes, Ossie J. Buckner

Master of Science in Chemical Sciences Theses

In the last few decades, N-heterocyclic carbenes (NHCs) have emerged as a powerful class of carbon-based ligands. Owing to their unique electronic and steric properties, they have been incorporated in a large variety of catalytically active metal complexes. One of the strategies that have been used to modify the ligand properties of NHCs is annulation with different carbo- and heterocyclic groups. It has been shown that annulation in the 4-5 position of the imidazole ring significantly influences the stability and the σ-donor/π- acceptor properties of the carbene species, and this may be used as a versatile tool for the fine-tuning …

A Pilot Study Analyzing Solvents In Electronic Cigarette “E-Liquid” Using High Performance Liquid Chromatography, Austin Matranga, Olivia Sellers, Matthew Gartner

Student Scholar Symposium Abstracts and Posters

Introduction: Electronic cigarettes, also known as an e-cigarette, are battery-powered devices that use a heating element to convert a liquid (“e-liquid”) into an inhalable aerosol. Their advertised use is as a nicotine delivery system minus the harmful chemicals. Since “e-liquids” and the electronic cigarettes are not regulated by the Food and Drug Administration, it is not well known under what conditions, if any, carcinogenic compounds are produced. There has been little research on the toxicity of electronic cigarettes. The aim of this study was to determine if formaldehyde or acetaldehyde are formed from the e-liquid by the high heat of …

Isothermal Titration Calorimetry Uncovers Substrate Promiscuity Of Bicupin Oxalate Oxidase, Hassan Ali Rana

Master of Science in Chemical Sciences Theses

Oxalate oxidase from Ceriporiopsis subvermispora (CsOxOx) is a manganese-dependent enzyme that catalyzes the oxygen-dependent oxidation of oxalate to form two moles of carbon dioxide and one mole of hydrogen peroxide. CsOxOx is the first oxalate oxidase reported to have a two beta barrel architecture (bicupin). The CsOxOx catalyzed oxidation of oxalate reaction can be monitored by coupling the product H₂O₂ to the horseradish peroxidase-catalyzed oxidation of 2,2'-azinobis-(3- ethylbenzthiazoline-6-sulphonic acid) and by membrane inlet mass spectrometry. Coupled enzyme assays often confound data interpretation. Isothermal titration calorimetry (ITC) measures heat changes that occur during a reaction. Therefore, ITC can …

Lead-Free Gunshot Residues As Forensic Evidence, Lashaundra A. Fambro

Master of Science in Chemical Sciences Theses

The analysis of gunshot residue (GSR) has been forensically relevant for many years and several methods are well characterized in scientific literature. However, the manufacture and distribution of lead-free alternatives to small caliber firearms ammunition is increasing rapidly as these types of rounds are more environmentally friendly and safer for use in indoor shooting ranges. Removing lead-containing compounds (e.g., lead styphnate) from the primer mixture eliminates a significant chemical marker vital to the legal precedent governing GSR analysis. The American Society for Testing and Materials (ASTM) standard ASTM E1588-95 is no longer applicable to such residues. With this emerging market, …

The Foundations Of Network Dynamics In An Rna Recombinase System, Jessica Anne Mellor Yeates

Dissertations and Theses

How life originated from physical and chemical processes is one of the great questions still unanswered today. Studies towards this effort have transitioned from the notion of a single self-replicating entity to the idea that a network of interacting molecules made this initial biological leap. In order to understand the chemical kinetic and thermodynamic mechanisms that could engender pre-life type networks we present an empirical characterization of a network of RNA recombinase molecules. We begin with 1-, 2-, and 3-molecular ensembles and provide a game theoretic analysis to describe the frequency dependent dynamics of competing and cooperating RNA genotypes. This …

Applications Of Nanoporous Gold Monoliths As Substrates For The Capture And Release Of Lectins And Glycoproteins, Allan Jonson Alla

Dissertations

Nanoporous gold (np-Au) monoliths are a free-standing nanostructured material with typical pore dimensions in the tens of nanometers range. The microstructure of np-Au resembles those of macroporous monolithic materials being used in chromatographic separations. The surfaces of np-Au monoliths were modified via flow methods with different ligands to develop affinity substrates for separations. A carbohydrate-modified np-Au monolith was prepared by immobilizing thiolated saccharides and further used to separate lectins. The np-Au monolith surface was also functionalized with self-assembled monolayers (SAMs) of α-lipoic acid (LA) followed by activation of carboxyl terminal groups to create amine reactive esters. Concanavalin A (Con A) …

The Synthesis Of 1,3-Difluoro-2-Methyl-4-Phenylbenzene From A One-Pot Reaction Of Difluorocarbene And 1-Phenyl-2-Methylcyclobutene, Ruth Felicitas Menger

Senior Honors Projects, 2010-2019

Previous studies show that 1,2-disubstituted cyclobutenes can be used in reaction with difluorocarbene to produce 1,3-difluorobenzenes. A pathway to the synthesis of these types of compounds is of interest due to their presence in fluoroquinolone antibacterials, resins, and insecticides. The synthesis is unique because the fluorine atoms from the difluorocarbene are not adjacent to each other when the ring expands to a benzene ring. This study focuses on the reaction of difluorocarbene with 1-phenyl-2-methylcyclobutene, which was synthesized in one-pot in 4 steps starting from 1-phenyl-1-propyne and zirconocene dichloride.

The Synthesis And Colloidal Characterization Of Several Triscationic Amphiphilic Antibacterial Agents, Kristin R. Mckenna

Senior Honors Projects, 2010-2019

M-P,12,12, a triscationic amphiphile, was characterized for its antibacterial and colloidal properties as well as its ability to associate with sodium dodecyl sulfate (SDS). This amphiphile has a mesitylene core, one pyridinium headgroup, and two dimethyldodecylammonium tails. The critical aggregation concentration (CAC) for M-P,12,12 was determined by three different methods. According to isothermal titration calorimetry (ITC), the CAC is 2.54 mM, conductivity studies determined the CAC to be 2.07 and the degree of ionization to be 0.188, and nuclear magnetic resonance (NMR) spectroscopy yielded a CAC value of 1.73 mM. The NMR study of the water-insoluble solid formed by M-P,12,12 …

The Effect Of Hofmeister Series Counterions On The Colloidal And Antimicrobial Properties Of Triple-Headed Cationic Amphiphiles, Kirstie A. Thompson

Senior Honors Projects, 2010-2019

Antibacterial resistance is becoming increasingly prominent, causing a great need for novel antibacterial products. This work focuses on developing an understanding of the relationship between counterion identity on colloidal and antibacterial activity for cationic amphiphiles. In an amphiphile series with three hydrophilic quaternary ammonium bromide head groups and one hydrophobic tail, the amphiphile with a linear hydrocarbon chain with 18 carbons is more antibacterial than those with longer or shorter tails. Counterion exchange of the bromide counterions with various Hofmeister series anions significantly affects both antibacterial and colloidal activity. The logarithm of critical aggregation concentration [log(CAC)] was found to have …

Quantifying The Use Of Chloroform Vapor Exposure To Improve The Adhesion Of Au Thin Films Onto Pmma, Kathleen T. Krist

Senior Honors Projects, 2010-2019

The metallization of Au onto plastics is an important processing step in applications such as the aerospace and automotive industries, the field of microelectronics, and the fabrication of microfluidic devices. While its corrosion resistance and excellent electrical and thermal conductivity make Au a useful choice, its inertness results in poor adhesion to polymer surfaces. Previous studies have indicated that exposing commercially available poly(methyl methacrylate) (PMMA) sheets to chloroform vapor following Au deposition significantly improves adhesion. In this study, we utilized electron-beam evaporation and magnetron sputtering to deposit Au thin films onto 1.50 mm thick PMMA and exposed the samples to …

Boron Difluoride Formazanate Copolymers With 9,9-Di-N-Hexylfluorene Prepared By Copper-Catalyzed Alkyne-Azide Cycloaddition Chemistry, Stephanie M. Barbon, Joe Gilroy

Chemistry Publications

The synthesis and characterization of copolymers based on boron difluoride formazanate (BF₂L) and 9,9-di-n-hexylfluorene (hex₂Fl) units are described. A series of model compounds [(BF₂L)-(hex₂Fl), (hex₂Fl)-(BF₂L)-(hex₂Fl), and (BF₂L)-(hex₂Fl)-(BF₂L)] were also studied in order to fully understand the spectroscopic properties of the title copolymer [(BF₂L)-(hex₂Fl)]_n. The model compounds and copolymers, which were synthesized by copper catalyzed alkyne-azide cycloaddition chemistry, exhibited high molar absorptivities (25,700-54,900 …

Zn(Ii), Cu(Ii), Sn(Ii), And Ni(Ii) And Other Metal Cations Do Not Prevent The Aggregation Of Hiapp, Charles Hoying

Honors Thesis

The Zn(II) metal ion has been shown to interact with Islet Amyloid Polypeptide (IAPP), a protein implicated in the progression of Type II Diabetes Mellitus, in such a way as to prevent the protein from aggregating into toxic fibers. We set out to find whether other metal ions might similarly prevent IAPP aggregation. Using Thioflavin T (ThT) spectroscopic assays, which measure fluorescence of ThT upon binding to aggregated IAPP, we observed a decrease in aggregation when incubated with Zn(II), Cu(II), Ni(II), and Sn(II). Atomic Force Microscopy (AFM), which can visualize fibril formation, revealed that the metals were not inhibiting IAPP …

A Direct Mechanism Of Ultrafast Intramolecular Singlet Fission In Pentacene Dimers, Eric G. Fuemmeler, Samuel N. Sanders, Andrew B. Pun, Elango Kumarasamy, Tao Zeng, Kiyoshi Miyata, Michael L. Steigerwald, X.-Y. Zhu, Matthew Y. Sfeir, Luis M. Campos, Nandini Ananth

Publications and Research

Interest in materials that undergo singlet fission (SF) has been catalyzed by the potential to exceed the Shockley–Queisser limit of solar power conversion efficiency. In conventional materials, the mechanism of SF is an intermolecular process (xSF), which is mediated by charge transfer (CT) states and depends sensitively on crystal packing or molecular collisions. In contrast, recently reported covalently coupled pentacenes yield ∼2 triplets per photon absorbed in individual molecules: the hallmark of intramolecular singlet fission (iSF). However, the mechanism of iSF is unclear. Here, using multireference electronic structure calculations and transient absorption spectroscopy, we establish that iSF can occur via …

The Chemistry Of Photography, Nichole Marie Witten

Senior Theses

People nowadays are used to instant gratification when it comes to taking photographs. They look at a digital display, click a button, and get a perfectly focused and lighted picture that they can see right away. New technologies enable people to have pocket-sized digital cameras, their smart phones, with them at all times, and they’re easy convenient, and fast. Behind a single lens reflex (SLR) film camera, the scenario is much different. More time is needed in framing the image and adjusting the aperture and shutter speed to get the correct exposure, and the film must be processed darkroom before …

From The Sewing Room To The Ballroom, The Evolution Of Ballroom Dance Costumes, Jessica Marie Russell

Senior Theses

Although I have danced all my life, I only began to ballroom dance and dance socially after starting college at the University of South Carolina. While dancing with the Carolina Ballroom Club, I learned some of the history of ballroom dance from our instructors, but I never quite understood how we went from having very conservative court dances to the wide variety of ballroom dances where dancers wear extravagant costumes. I also have been sewing since I was a child; I helped do minor repairs in the costume room for ballet productions, and recently began making clothing for myself. I …

Thiophene Based Molecular Sensors Towards Mercury Detection, Austin K. Shigemoto, Carolyn N. Virca, Sam Underwood, Lauren Shetterly, Theresa M. Mccormick

Student Research Symposium

Toxic heavy metals such as mercury have increased in concentration in the environment due to pollution. Inorganic mercury in the environment can be later converted to a more toxic form: methylmercury. Regular consumption of fish containing methylmercury can lead to several cognitive and motor disorders as well as Minamata disease. The current methods used to detect both methylmercury and inorganic mercury in sea life and drinking water involve long sample preparation and cost. In order to more efficiently track this toxic metal in the environment and identify contaminated food and water sources, a cheaper and faster method of detection is …

The Evolution Of The Surface Of The Mineral Schreibersite In Prebiotic Chemistry, Nikita L. La Cruz, Danna Qasim, Heather Abbott-Lyon, Claire Pirim

Faculty Articles

We present a study of the reactions of the meteoritic mineral schreibersite (Fe,Ni)3P, focusing primarily on surface chemistry and prebiotic phosphorylation. In this work, a synthetic analogue of the mineral was synthesized by mixing stoichiometric proportions of elemental iron, nickel and phosphorus and heating in a tube furnace at 820 °C for approximately 235 hours under argon or under vacuum, a modification of the method of Skála and Drábek (2002). Once synthesized, the schreibersite was characterized to confirm the identity of the product as well as to elucidate the oxidation processes affecting the surface. In addition to characterization of the …

The Synthesis Of Angucyclines Using An Intramolecular Bradsher Cycloaddition, Abdullah Allaoa, Tony E. Nicolas

Publications and Research

The Angucyclines are natural products which possess a broad spectrum of biological properties. Of particular interest are the natural products which contain the cis-hydroxyl motif at the AB ring junction. Their synthesis is particularly challenging. Our model study has resulted in the synthesis of a model of the angucyclines with the required cis-hydroxyl features. The present work will apply the previously developed chemistry to an intramolecular version which will lead to the synthesis of the ABC ring system

Dynamics Of Prebiotic Rna Reproduction Illuminated By Chemical Game Theory, Jessica Anne Mellor Yeates, Christian Hilbe, Martin Zwick, Martin. A. Nowak, Niles Lehman

Chemistry Faculty Publications and Presentations

Many origins-of-life scenarios depict a situation in which there are common and potentially scarce resources needed by molecules that compete for survival and reproduction. The dynamics of RNA assembly in a complex mixture of sequences is a frequency-dependent process and mimics such scenarios. By synthesizing Azoarcus ribozyme genotypes that differ in their single-nucleotide interactions with other genotypes, we can create molecules that interact among each other to reproduce. Pairwise interplays between RNAs involve both cooperation and selfishness, quantifiable in a 2 × 2 payoff matrix. We show that a simple model of differential equations based on chemical kinetics accurately predicts …

Innovative Synthesis Of Diltiazem/Clentiazem Analogs, Emelyn Magtanong

Journal of Interdisciplinary Undergraduate Research

Cardiovascular disease defines disorders of the heart and blood vessels, and is the number one cause of death in America. Diltiazem and clentiazem are common calcium channel blockers incorporated into drugs used to treat various cardiovascular diseases. Methods to synthesize 5-[2-(dimethylamino)ethyl]-8-hydroxy-2,3,4,5-tetrahydro-1,5-benzothiazepin-4-one, an analog of the core of diltiazem and clentiazem, using cost-efficient starting materials allows for affordable treatment and increased availability to affected individuals. N-(N,N-dimethylethanamine)-4-aminophenol can be oxidized to form a quineoneimine, which can be further reacted with 3-mercaptopropionic acid via Michael addition. Subsequent addition of a coupling reagent, N,N'-dicyclocarbodiimide (DCC),¹ produces 5-[2-(dimethylamino)ethyl]-8-hydroxy-2,3,4,5-tetrahydro-1,5-benzothiazepin-4-one, analogous to the core …

Inhibiting Fatty Acid Synthase In Rapidly Dividing Cells: Synthesis Of 5-(Alkylthio)-1h-Benzo[D]Imidazole-2,6-Diones, Andy Hausted

Journal of Interdisciplinary Undergraduate Research

Prostate and breast cancer are the number one and number two cancer sites, respectively, for male and females within the United States.1 Increased levels of the enzyme fatty acid synthase have been found in rapidly dividing cancer cells. This enzyme is responsible for the de novo synthesis of fatty acids in human cells, which are essential to cell growth and survival. The goal then for this research is to synthesize and design a new synthesis of 5-(alkylthio)-1Hbenzo[ d]imidazole-2,6-diones intended to successfully inhibit fatty acid synthase (FASN) by binding allosterically to the thioesterase domain of FASN. Thus by selectively inhibiting FASN …

Enhancing The Reduction Potential Of Quinones Via Complex Formation, Binod Nepal, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Quantum calculations are used to study the manner in which quinones interact with proton-donating molecules. For neutral donors, a stacked geometry is favored over a H-bond structure. The former is stabilized by charge transfers from the N or O lone pairs to the quinone’s π* orbitals. Following the addition of an electron to the quinone, the radical anion forms strong H-bonded complexes with the various donors. The presence of the donor enhances the electron affinity of the quinone. This enhancement is on the order of 15 kcal/mol for neutral donors, but up to as much as 85 kcal/mol for a …

Wrinkled1 Rescues Feedback Inhibition Of Fatty Acid Synthesis In Hydroxylase-Expressing Seeds, Neil D. Adhikari, Philip D. Bates, John Browse

Faculty Publications

Previous attempts at engineering Arabidopsis (Arabidopsis thaliana) to produce seed oils containing hydroxy fatty acids (HFA) have resulted in low yields of HFA compared with the native castor (Ricinus communis) plant and caused undesirable effects, including reduced total oil content. Recent studies have led to an understanding of problems involved in the accumulation of HFA in oils of transgenic plants, which include metabolic bottlenecks and a decrease in the rate of fatty acid synthesis. Focusing on engineering the triacylglycerol assembly mechanisms led to modest increases in the HFA content of seed oil, but much room for …