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Structure And Thermodynamics Of Polyglutamine Peptides And Amyloid Fibrils Via Metadynamics And Molecular Dynamics Simulations, Riley Workman Aug 2018

Structure And Thermodynamics Of Polyglutamine Peptides And Amyloid Fibrils Via Metadynamics And Molecular Dynamics Simulations, Riley Workman

Electronic Theses and Dissertations

Aggregation of polyglutamine (polyQ)-rich polypeptides in neurons is a marker for nine neurodegenerative diseases. The molecular process responsible for the formation of polyQ fibrils is not well understood and represents a growing area of study. To enable development of treatments that could interfere with aggregation of polyQ peptides, it is crucial to understand the molecular mechanisms by which polyQ peptides aggregate into fibrils. Many experimental techniques have been employed to probe polyQ aggregation, however, observations from these studies have not lead to a unified understanding of the properties of these systems, instead yielding competing, fragmented theories of polyQ aggregation. This …

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Synthesis Of Modified Biginelli Compounds, Michelle Sarah Collins Aug 2018

Synthesis Of Modified Biginelli Compounds, Michelle Sarah Collins

Student Theses and Dissertations

The Biginelli reaction has been a distinguished reaction for many years. Their products, the Dihydropyrimidones have been shown to contain a vast array of bioactivity especially when they contain other known bioactive functional groups. Here in we discuss different pathways that these DHPM products can be taken down to combine them with other such bioactive functional groups. We explored the addition of alkene and aldehyde groups to the Biginelli compounds in hopes of synthesizing potential drug candidates. We believe the synthesis of the aldehyde group on the DHPM compounds is a gateway to obtaining the hybrid drug activity we so …

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3-Hydroxy-2-(4- Methylphenyl)-4h-Chromen-4-One, Clifford W. Padgett, Will E. Lynch, Kirkland Sheriff, Raven Dean, Sarah Zingales Aug 2018

3-Hydroxy-2-(4- Methylphenyl)-4h-Chromen-4-One, Clifford W. Padgett, Will E. Lynch, Kirkland Sheriff, Raven Dean, Sarah Zingales

Chemistry: Faculty Publications (1990-2023)

Our work in the area of carbon-monoxide-releasing mol­ecules led to the synthesis and crystallization of new flavone derivatives as inter­mediates. Herein we report the first crystal structure of the title compound, C16H12O3, a hy­droxy-substituted flavone where the 2-phenyl group has been replaced by a p-tolyl group. The introduction of the 3-hy­droxy group allows the formation of inter­molecular O—H...O=C hydrogen bonds, used to build centrosymmetric R22(10) ring motifs in the crystal.

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Design And Synthesis Of Circadian Clock Modulators And The Study Of Lov Domain Protein Lkp2 In Arabidosis Thaliana And Brassica Rapa, Aditi Nagar Aug 2018

Design And Synthesis Of Circadian Clock Modulators And The Study Of Lov Domain Protein Lkp2 In Arabidosis Thaliana And Brassica Rapa, Aditi Nagar

Chemistry Theses and Dissertations

Circadian rhythms are self-autonomous endogenous clocks synchronized with the rotation of the Earth. With the Earth’s rotation and revolution on its axis, the internal clock undergoes oscillation in the period of ~24 hour and governs day to day activities in most organisms. In humans, it regulates the day to day physiological activities. Today’s modern lifestyle has an impact on health: shift work, jet lag, and irregular eating habits contribute to the misalignment of the endogenous circadian oscillator, thereby, increasing the risk of many metabolic disorders including diabetes, irregular blood pressure, sleep disorders, obesity, depression, and cancer. The primary goal of …

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Thiophene-Based Molecular Sensors Towards The Selective Detection Of Mercury(Ii) And Other Metals, Austin Kazuo Shigemoto Aug 2018

Thiophene-Based Molecular Sensors Towards The Selective Detection Of Mercury(Ii) And Other Metals, Austin Kazuo Shigemoto

Dissertations and Theses

This work describes several thiophene-based molecular sensors and various modifications aimed to improve and understand the photophysical and supramolecular properties, such as the association constant (Ka) and selectivity, towards the development of a selective mercury(II) sensor. From the first generation of sensors containing pyridine and thiophene groups, it was determined that thiophene can offer good selectivity for mercury(II) against other transition metal ions, and provide a ratiometric absorption and fluorescent response. The projects following this focused on improving the Ka of the first generation of sensors through several different strategies. Substitution of thiophene for dibenzothiophene was …

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Evidence For The Formation Of A Radical-Mediated Flavin-N5 Covalent Intermediate, Yumin Dai, Hannah Valentino, Pablo Sobrado Aug 2018

Evidence For The Formation Of A Radical-Mediated Flavin-N5 Covalent Intermediate, Yumin Dai, Hannah Valentino, Pablo Sobrado

Chemistry Faculty Research & Creative Works

The redox-neutral reaction catalyzed by 2-haloacrylate hydratase (2-HAH) leads to the conversion of 2-chloroacrylate to pyruvate. Previous mechanistic studies demonstrated the formation of a flavin-iminium ion as an important intermediate in the 2-HAH catalytic cycle. Time-resolved flavin absorbance studies were performed in this study, and the data showed that the enzyme is capable of stabilizing both anionic and neutral flavin semiquinone species. The presence of a radical scavenger decreases the activity in a concentration-dependent manner. These data are consistent with the flavin iminium intermediate occurring by radical recombination.

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Fabrication Of Mnox/Mwcnts-Gc Nanocatalyst For Oxygen Evolution Reaction, Yaser M. Asal Mr, Islam M. Al-Akraa Dr, Amr M. Arafa Eng. Aug 2018

Fabrication Of Mnox/Mwcnts-Gc Nanocatalyst For Oxygen Evolution Reaction, Yaser M. Asal Mr, Islam M. Al-Akraa Dr, Amr M. Arafa Eng.

Chemical Engineering

Manganese oxide (MnOx) and multiwalled carbon nanotubes (MWCNTs) are intended to modify the GC electrode for oxygen evolution reaction (OER). Optimization of MnOx loading is carried out and the deposition of 55 cycles was sufficient to obtain the highest activity toward OER. The stability of the catalyst is enhanced by the addition of MWCNTs. As a result, an amount of 22 kWh/Kg of O2 of energy is saved. Several techniques including cyclic voltammetry, linear sweep voltammetry, chronoamperometry, chronopotentiometry, field-emission scanning electron microscopy, and energy dispersive X-ray spectroscopy will be combined to track the catalyst activity and to determine its …

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Ultrafast Laser Filament-Induced Fluorescence Spectroscopy Of Uranyl Fluoride, P. J. Skrodzki, M. Burger, L. A. Finney, F. Poineau, S. M. Balasekaran, J. Nees, K. R. Czerwinski, I. Jovanovic Aug 2018

Ultrafast Laser Filament-Induced Fluorescence Spectroscopy Of Uranyl Fluoride, P. J. Skrodzki, M. Burger, L. A. Finney, F. Poineau, S. M. Balasekaran, J. Nees, K. R. Czerwinski, I. Jovanovic

Chemistry and Biochemistry Faculty Research

Uranyl fluoride (UO2F2) is a compound which forms in the reaction between water and uranium hexafluoride, a uranium containing gas widely used for uranium enrichment. Uranyl fluoride exhibits negligible natural background in atmosphere; as a result, its observation implies the presence and active operation of nearby enrichment facilities and could be used as a tracer for treaty verification technologies. Additionally, detection of UO2F2 has a potential application in guiding remediation efforts around enrichment facilities. Laser-induced fluorescence (LIF) has been proposed in the past as a viable technique for the detection and tracking of UO2F2. We demonstrate that ultrafast laser filamentation …

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Tof-Sims Analysis Of Plant Seed Interactions With Plant Growth-Promoting Bacteria, Tammy Pheuphong, Rachel Komorek, Xiao-Ying Yu Aug 2018

Tof-Sims Analysis Of Plant Seed Interactions With Plant Growth-Promoting Bacteria, Tammy Pheuphong, Rachel Komorek, Xiao-Ying Yu

STAR Program Research Presentations

The use of time-of-flight secondary ion mass spectrometry (ToF-SIMS) in plant biology is a relatively unexplored and quickly developing field. The majority of research in plant SIMS involves the application of ToF-SIMS to study dried wood tissues, and only a handful of studies apply SIMS on plant stems, roots, and/or seeds. Our project provides a brief description and review of previous work using SIMS on plant stems, roots, and/or seeds, along with an emphasis on the sample preparation in each study. Additionally, the use of Brachypodium distachyon (Brachypodium) as a model system for research on grasses has also become more …

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Manganese Oxide/Hemin-Functionalized Graphene As A Platform For Peroxynitrite Sensing, Haitham F. Kalil, Shaimaa Maher, Tiyash Bose, Mekki Bayachou Aug 2018

Manganese Oxide/Hemin-Functionalized Graphene As A Platform For Peroxynitrite Sensing, Haitham F. Kalil, Shaimaa Maher, Tiyash Bose, Mekki Bayachou

Chemistry Faculty Publications

Peroxynitrite (ONOO−, PON) is a powerful oxidizing agent generated in vivo by the diffusion-limited reaction of nitric oxide (NO) and superoxide (O2˙−) radicals. Under oxidative stress, cumulated peroxynitrite levels are associated with chronic inflammatory disorders and other pathophysiological conditions. The accurate detection of peroxynitrite in biological systems is important, not only to understand the genesis and development of diseases, but also to explore and design potential therapeutics. Herein, a manganese oxide/hemin-modified graphene interface is explored as a platform for peroxynitrite amperometric detection. Hemin-functionalized reduced graphene oxide was further modified with manganese oxide nanoparticles to provide a …

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Cell-Free Studies Of Catalytic Dna Cleavage By Ruthenium Polypyridyl Complexes (Rpcs) Containing Redox-Active Intercalating Ligands, Enantiomeric Separation And Semi-Prep Scale Purification Of Rpcs, Cynthia Ann Griffith Aug 2018

Cell-Free Studies Of Catalytic Dna Cleavage By Ruthenium Polypyridyl Complexes (Rpcs) Containing Redox-Active Intercalating Ligands, Enantiomeric Separation And Semi-Prep Scale Purification Of Rpcs, Cynthia Ann Griffith

Chemistry & Biochemistry Dissertations - Archive

Herein, we report the ruthenium (II) polypyridyl complexes (RPCs), [(phen)₂Ru(tatpp)] ²⁺ (3²⁺) and [(phen)₂Ru(tatpp)Ru(phen)₂] ⁴⁺ (4⁴⁺) are shown to cleave DNA in cell-free studies in the presence of a mild reducing agent, i.e. glutathione (GSH), in a manner that is enhanced upon lowering the [O₂] . Reactive oxygen species (ROS) are involved in the cleavage process as hydroxy radical scavengers attenuate the cleavage activity. Cleavage experiments in the presence of superoxide dismutase (SOD) and catalase reveal a central role for H₂O₂ as the immediate precursor for hydroxy radicals. A mechanism is proposed which explains the inverse [O₂] dependence and ROS …

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New Methods For Discovery, Fingerprinting, And Analysis Of Cannabis Sativa Natural Products, Allegra Leghissa Aug 2018

New Methods For Discovery, Fingerprinting, And Analysis Of Cannabis Sativa Natural Products, Allegra Leghissa

Chemistry & Biochemistry Dissertations - Archive

Cannabis sativa is an herbaceous annual that has always been of great interest due to its uses in the manufacturing of textiles and cordage, as well as for its medicinal properties. The two main bioactive components of C. sativa are cannabinoids and terpenes; the former confer the medicinal and pharmaceutical benefits, as well as the psycho-activity, to the plant, while the latter are largely responsible for aroma and flavor. Because of the importance of both sets of analytes, it is crucial to have a comprehensive understanding and characterization of these compounds, and different methods have been developed to address these …

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New Strategies For Catalytic C-H And Olefin Hydrosilylation, Parham Asgari Aug 2018

New Strategies For Catalytic C-H And Olefin Hydrosilylation, Parham Asgari

Chemistry & Biochemistry Dissertations - Archive

In the works described here, new catalytic hydrosilylation strategies were explored. First, a highly selective, bond functionalization strategy, achieved via relay of two transition metal catalysts and use of traceless acetal directing groups, was introduced. Specifically, this approach involves the relay of Ir-catalyzed hydrosilylation and Rh-catalyzed ortho-C–H silylation. This acetal directing group strategy was used for catalytic ortho-C–H silylation of phenols and benzoate esters derivatives. Additionally, we developed a transition metal free, catalytic vinyl arenes hydrosilylation method. We describe our discovery on unprecedented, sustainable HAT process and report a mechanism involving Lewis base-catalyzed, complexation-induced HAT (LBCI-HAT), followed by highly selective …

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Fluorescently Labeled Sirnas And Their Theranostic Applications In Cancer Gene Therapy, Stephen David Kozuch Aug 2018

Fluorescently Labeled Sirnas And Their Theranostic Applications In Cancer Gene Therapy, Stephen David Kozuch

Seton Hall University Dissertations and Theses (ETDs)

Gene therapy has emerged as a promising precision nano-medicine strategy in the treatment of numerous diseases including cancer. At the forefront of its utility are the applications of short-interfering RNA (siRNA), that silence oncogenic mRNA expression leading to cancer cell death through the RNA interference (RNAi) pathway. Despite the therapeutic potential, siRNAs are limited by poor pharmacological properties, which has hindered their translation into the clinic. Recent studies, however, have highlighted the applications of modified siRNAs, including the use of fluorescent probes and siRNA nanostructures in cancer detection and treatment. The siRNAs reported in this thesis are designed to target …

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Electrogenerated Chemiluminescence Of Transition Metal Octaethylporphyrin And Tetraphenylporphyrin/Tri-N-Propylamine System, Jamie Lee Gray Aug 2018

Electrogenerated Chemiluminescence Of Transition Metal Octaethylporphyrin And Tetraphenylporphyrin/Tri-N-Propylamine System, Jamie Lee Gray

Graduate Theses/Dissertations

The electrogenerated chemiluminescence (ECL) of octaethylporphyrin (OEP), tetraphenylporphyrin (TPP) and a series of metal-ligand porphyrin complexes (Zinc, Copper, Palladium, Platinum, Ruthenium, Vanadium, Cobalt and Nickel) in CH2Cl2 is reported. ECL was generated upon sweep to positive potentials using tri-n-propylamine (TPrA) as an oxidative-reductive coreactant. ECL efficiencies were between 0.010 and 0.770 using Ru(bpy)3(PF6)2 (bpy = 2,2’-bpyridine) as a relative standard (ecl = 1). The ECL intensity peaks at a potential corresponding to oxidation of the complexes and TPrA, suggesting that the same excited states are formed in both photoluminescence and ECL. Although the ECL was weaker than corresponding PL efficiencies, …

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Nmr Spectroscopic Properties Of Nucleotides, And A New Method Of Numeric Calculation Of Raman Intensities For Organic Molecules, William R. Ehrhardt Aug 2018

Nmr Spectroscopic Properties Of Nucleotides, And A New Method Of Numeric Calculation Of Raman Intensities For Organic Molecules, William R. Ehrhardt

Graduate Theses/Dissertations

General and accurate computational methodologies are currently lacking for large chemical systems. This is primarily due to the computational expense required to perform calculations on systems with one hundred or more atoms. Calculated spectroscopic properties could aid in the process of elucidating structural features of large biologically relevant molecules if accurate and inexpensive methods are developed. Towards this end the first steps were taken to design a general methodology for predicting NMR chemical shifts of large nucleic acid systems. It was found that HF and semi-empirical methods were not sufficient for optimization of nucleobases, and therefore larger nucleotide or nucleic …

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Studies Towards The Total Synthesis Of Imidazole-Containing Natural Products, Lawton Anthony Ii Seal Aug 2018

Studies Towards The Total Synthesis Of Imidazole-Containing Natural Products, Lawton Anthony Ii Seal

Chemistry & Biochemistry Dissertations - Archive

Nature has inspired man in all aspects of life, chemistry included. The first antibiotic ever discovered came from nature, and since then, chemists have been probing nature for insights to guide drug discovery and development. Alkaloids are a class of naturally occurring molecules which contain nitrogen atoms and can be found in all forms of life. Imidazole is common structural unit found in many natural molecules, from the simple amino acid histamine to more complex structures like the marine sponge derived alkaloid palau’amine. Many imidazole-containing natural products are biologically active, such as inhibiting the growth of tumors, possessing antibacterial properties, …

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Separation, Detection, And Quantitation Of Underivatized Carbohydrates Using Liquid Chromatography- Electrospray Ionization-Triple Quadrupole- Tandem Mass Spectrometry, Jonathan B. Thacker Aug 2018

Separation, Detection, And Quantitation Of Underivatized Carbohydrates Using Liquid Chromatography- Electrospray Ionization-Triple Quadrupole- Tandem Mass Spectrometry, Jonathan B. Thacker

Chemistry & Biochemistry Dissertations - Archive

Carbohydrate analysis has many important implications in health, consumer products, and industrial processes. Among many possible analytical techniques for their analysis, mass spectrometry (MS) is an attractive approach, offering high sensitivity and specificity. In particular, electrospray ionization (ESI)-MS affords several advantages over other ionization techniques: the ability for direct coupling with upstream chemical separation techniques, its suitability for quantitation, and its compatibility with relatively inexpensive quadrupole mass analyzers for the analysis of high molecular weight compounds. However, the sensitivity of ESI-MS towards carbohydrates tends to be much less than for other classes of compounds, such as peptides. This is due …

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Characterization And Remediation Of Wastewater From Unconventional Oil And Gas Development, Tiffany Michelle Liden Aug 2018

Characterization And Remediation Of Wastewater From Unconventional Oil And Gas Development, Tiffany Michelle Liden

Chemistry & Biochemistry Dissertations - Archive

Increasing energy demands from the nation and technological advancement in well development have led to the rapid expansion of unconventional oil and gas extraction. Current disposal methods for wastewater generated from the development of low porosity formations are not environmentally sustainable. The billions of gallons of highly variable, chemically-rich wastewater, referred to as produced water, is frequently sequestered in subsurface, non-productive stratum through injection wells. Cost-effective options to treat produced water are being sought as an alternative to injection wells to prevent the loss of water from the water cycle and decrease anthropologically induced seismic events. Ultimately, it has been …

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Redox And Non-Redox Reactions Catalyzed By Biomimetic Flavin-Based Organocatalysts And The Discovery Of Selective Oxidation Methods For The Preparation Of N-Heterocycles, Pawan Thapa Aug 2018

Redox And Non-Redox Reactions Catalyzed By Biomimetic Flavin-Based Organocatalysts And The Discovery Of Selective Oxidation Methods For The Preparation Of N-Heterocycles, Pawan Thapa

Chemistry & Biochemistry Dissertations - Archive

In nature, flavoproteins (FMN and FAD) are known to catalyze several chemical transformations which play a vital role in the growth, development, and survival of organisms. They are involved in one-electron and two-electron transfer reactions, photo-induced electron transfer reactions, dehydrogenase reactions, oxidative atom transfer reactions and also rare non-redox reactions. Their enhanced stability and ability to turn over in presence of dioxygen has inspired synthetic chemists, including our group, to perform biomimetic transformations within a range of function of natural flavoproteins. In chapter 1, both intramolecular and intermolecular dehydrogenative coupling between the alpha carbon of tertiary amines and various nitrogen, …

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Chemical Strategies For Drug Development Of Fucose-Truncated Ipomoeassin F Analogues, Melissa Hirsch Aug 2018

Chemical Strategies For Drug Development Of Fucose-Truncated Ipomoeassin F Analogues, Melissa Hirsch

Graduate Theses and Dissertations

Natural product synthesis has many applications in the field of chemical biology, due to the protein binding affinity to the complex three-dimensional structure. However, synthetic and structure-activity relationship studies concerning certain drug targets are scarce. For example, members of the ipomoeassin family have exhibited anti-cancer properties, but cost-effective optimization of these compounds has not yet been extensively studied. Ipomoeassin F, a natural glycoresin isolated from the leaves of the Ipomoea squamosa plant in the Suriname rainforest, has shown high cytotoxicity, with IC50 values measured at the low nanomolar range. Two studies by Postema and Fuerstner have outlined synthesis pathways for …

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Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor Aug 2018

Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor

Electronic Theses and Dissertations

Metabolomics, the study of small molecules in biological systems, has enjoyed great success in enabling researchers to examine disease-associated metabolic dysregulation and has been utilized for the discovery biomarkers of disease and phenotypic states. In spite of recent technological advances in the analytical platforms utilized in metabolomics and the proliferation of tools for the analysis of metabolomics data, significant challenges in metabolomics data analyses remain. In this dissertation, we present three of these challenges and Bayesian methodological solutions for each. In the first part we develop a new methodology to serve a basis for making higher order inferences in metabolomics, …

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Synthesis, Characterization, And Applications Of Ammonium/Phosphonium Chitosan Derivatives For Investigative Dna Interactions, Quinton Kirk Wyatt Aug 2018

Synthesis, Characterization, And Applications Of Ammonium/Phosphonium Chitosan Derivatives For Investigative Dna Interactions, Quinton Kirk Wyatt

Graduate Theses/Dissertations

Chitosan is examined as a non-viral vector capable of efficient gene delivery due to its favorable properties such as biodegradability, biocompatibility, and is non-toxic to mammalian cells. Cell modifications and vector permeability are enhanced in non-viral vectors that incorporate electrostatic interactions. This work synthesizes cationic (N+, P+) chitosan derivatives, to enhance electrostatic interactions towards nucleotides, using amide coupling agents EDC and HOBt. The final chitosan derivatives will bear cationic functional groups (N+, P+) with various alkyl groups (Me, Et, Pr, Ph) to examine their affinities to nucleotides and antifungal properties. mPEG grafted …

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Development Of Rapid, Homogeneous Assay For Investigating Isopeptide Bond Formation Using Fluorescence Polarization/Depolarization Measurements, Samuel Patricc Kasson Aug 2018

Development Of Rapid, Homogeneous Assay For Investigating Isopeptide Bond Formation Using Fluorescence Polarization/Depolarization Measurements, Samuel Patricc Kasson

Graduate Theses/Dissertations

Autocatalytic intramolecular isopeptide bonds have been found in nature in certain gram-positive bacterial pilus structures. Recently, splitting of these domains that are capable of autocatalytic intramolecular isopeptide bond formation have been applied to create stable, selective, bio-orthogonal Catcher/Tag systems. The CnaB2 domain found in the FbaB pilus structure of Streptococcus pyogenes, has yielded the Catcher/Tag, Protein/Peptide systems termed SpyCatchter and SpyTag. Recent study has focused on tag optimization, stability and bio-orthogonality evaluation, along with applications in bioconjugation. I have recombinantly expressed SpyCatcher and SpyTag-fused proteins in E.coli, and conjugated them to fluorescent probes in order for use in fluorescence polarization/depolarization …

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Learning Chemistry In English: Challenges Faced By Non-Native English Speakers, Arwa A. Alshehri Aug 2018

Learning Chemistry In English: Challenges Faced By Non-Native English Speakers, Arwa A. Alshehri

Graduate Theses/Dissertations

Every year many international students come to study in the United States. In addition to all the challenges associated with coming to a new country, non-native English speakers (NNES) face the additional challenge of having to learn their content in English. Therefore, in this project, I recruited NNES participants from general chemistry courses since preliminary inquiries indicated that they have the largest enrollments. Because there were relatively few students at MSU who are non-native English speakers studying chemistry, I used a case study design to be able to extract generalizations from an in-depth study of a few individuals. The aim …

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Investigations Into Factors Affecting The Wpd-Loop In The Protein Tyrosine Phosphatases Yoph And Ptp1b, Gwendolyn Moise Aug 2018

Investigations Into Factors Affecting The Wpd-Loop In The Protein Tyrosine Phosphatases Yoph And Ptp1b, Gwendolyn Moise

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research in this dissertation documents connections between the primary amino acid sequence of proteins, the dynamics of proteins, and their catalytic function. This research project studied two proteins called protein-tyrosine phosphatases (PTPs): the human enzyme PTP1B, and the bacterial enzyme YopH. PTP1B is a human enzyme that down regulates the insulin receptor on the outer cellular membrane, and causes the insulin receptor to be less responsive to insulin. A deeper knowledge of how PTP1B is different from other human PTPs might be useful in designing drugs to increase insulin sensitivity in diabetics. Yersinia Pestis is the bacteria that caused …

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Synthetic And Theoretical Studies For Cyclization Reactions To Form C-C And C-N Bonds, Nicholas Jentsch Aug 2018

Synthetic And Theoretical Studies For Cyclization Reactions To Form C-C And C-N Bonds, Nicholas Jentsch

Dissertations

Natural product total synthesis provides an alternative method for obtaining medicinally relevant compounds in a more efficient process with higher yields than what nature can provide. Natural products pose significant synthetic challenges due to the unique heterocyclic skeletons with fused and spirocyclic ring systems. Therefore, it is paramount to develop efficient reaction methodologies targeting substructures such as cyclic ureas and spiro[4.5]decanes which are prominent among marine natural products and Lycopodium alkaloids, respectively. Presented here is a compilation of research seeking to develop synthetic methods for the construction of cyclic moieties such as those previously mentioned. The objectives that are addressed …

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Computational Study Of The Nature Of Tetrel Bond, Yama Aman Aug 2018

Computational Study Of The Nature Of Tetrel Bond, Yama Aman

Masters Theses

For more than a hundred years, the type of a chemical bond has been distinguished according to the relative electronegativities of chemical units at the ends of a bond. Whereas, the bond of unequally electronegative on both ends is called a polar covalent or even ionic bond or a non-polar covalent bond in case of both equal. Regardless the type of bonded elements, the whole idea for the bond was believed to be electron driven only. In the 20th century the development of the idea, that not just the electronic relation but specific elements are also able to characterize the …

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Immobilization Of Gold Nanoparticles On Nitrided Carbon Fiber Ultramicroelectrodes By Direct Reduction, George Affadu-Danful Aug 2018

Immobilization Of Gold Nanoparticles On Nitrided Carbon Fiber Ultramicroelectrodes By Direct Reduction, George Affadu-Danful

Electronic Theses and Dissertations

Due to enhanced properties such as large surface area-to-volume ratio, metal nanoparticles are often employed as catalysts for various applications. However, most studies involving nanoparticle catalysts have been conducted on collections of particles rather than single nanoparticles. Results obtained for ensemble systems can be difficult to interpret due to variations in particle loading and interparticle distance, which are often challenging to control and characterize. In this study, two immobilization strategies for incorporating gold nanoparticles (AuNPs) on carbon fiber ultramicroelectrodes (UMEs) were compared with the goal of extending these techniques to nanoelectrodes for studies of single AuNPs. Both layer-by-layer deposition of …

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3d-Printed Fluidic Devices And Incorporated Graphite Electrodes For Electrochemical Immunoassay Of Biomarker Proteins, Abdulhameed Alabdulwaheed Aug 2018

3d-Printed Fluidic Devices And Incorporated Graphite Electrodes For Electrochemical Immunoassay Of Biomarker Proteins, Abdulhameed Alabdulwaheed

Electronic Theses and Dissertations

Biomarkers are measurable indicators of health status or disease state that can be used for diagnosis and may help guide patient treatment strategies. Enzyme-linked immunosorbent assays (ELISA) and other many clinical techniques currently used for measuring biomarker proteins lack sensitivity, demand high analysis cost, are often not well-suited for measuring multiple biomarkers in a single sample, and require long analysis times. Here, we demonstrate simple, low-cost 3D-printed flow-through devices with integrated electrodes modified with gold nanoparticles (AuNPs) for electrochemical immunoassays of S100B, a biomarker protein related to conditions like skin cancer and brain injuries. Flow-through devices are fabricated from photocurable-resin …

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