Chemistry Commons^™

Stability Of Bimetallic Clusters In Protein Model Systems, Sean Hartnett

Master’s Theses

Heterobimetallic cofactors are commonly found in proteins and allow them to perform unique chemical processes that would otherwise not be possible. The interactions between these metals allow the protein to accomplish difficult chemical transformations. Previously, the thermodynamic stability of a Fe^II /Mn^II cluster in the dinucleating ligand F-HXTA (5-fluoro-2-hydroxy-1,3-xylene-α,α′-diamine-N,N,N′,N′-tetraacetic acid) has been investigated in our lab as a model of cluster assembly in the proteins ribonucleotide reductase (RNR) and R2-like ligand binding oxidases (R2lox). By measuring equilibrium concentrations of F-HXTA complexes via ¹⁹F-NMR, it was found that the equilibrium for metal exchange between the homobimetallic …

Functionalizing Titanium Implants With Bioactive Peptides To Increase Osseointegration, Neil Bernard

Williams Honors College, Honors Research Projects

Orthopedic surgeries have continued to increase, but the material of choice remains constant: titanium. Titanium has become the benchmark implant material due to its durability and non-immunogenic properties. However, while high rates of success are correlated with joint replacement surgery, certain patients with predisposed diseases such as diabetes or arthritis may have increased complications.¹ This can be due to lack of osseointegration due to decreased bone formation and mineralization,² which will lead to increased rates of infection or aseptic loosening of the implant from the bone. ³ Current methods to alleviate these complications include invasive revisional surgeries, which …

Tunable Surface Interactions In Adsorbing Polymer Solutions, Sorour Hosseini

Open Access Theses & Dissertations

A simple formalism is suggested, to calculate the most likely configuration of a finite polymer, between two surfaces on which the monomers can adsorb. Grafted polymers typically enhance the stability of colloidal dispersions, via the long ranged steric repulsion due to the overlap of their polymer brushes, which can be thicker that the typical range of the DLVO interactions. However, if the polymers are adsorbing on the colloidal surfaces, there is the possibility of bridge formation between particles and therefore long-range attractions are induced (a procedure commonly used for the flocculation of colloidal suspensions). The two effects are competing and …

Development Of A Dna Aptamer That Specifically Inhibits Human Carbonic Anhydrase Ii, Afroz Karim

Open Access Theses & Dissertations

Carbonic anhydrases (CA) are a family of enzymes that catalyze the rapid interconversion of carbon dioxide and water to bicarbonate. Carbonic anhydrase II is the most abundant protein in the cytosol. CA II inhibitors are emergent therapeutic targets for the development of antiglaucoma agents. Glaucoma is a disease affecting large number of people and characterized by an elevated intraocular pressure due to excessive secretion of aqueous humor. The enzyme CA II is responsible for the secretion of aqueous humor. Isoforms of CA II such as CA IV and CA I are present in many tissues and organs other than the …

Exposure Of Kidney Bean (Phaseolus Vulgaris) Plants To Coated And Uncoated Zinc Oxide Nanomaterials Under Different Soil Conditions: Effects On Plant Growth And Seed Quality, Illya Aidee Medina Velo

Open Access Theses & Dissertations

Soil exposure to engineered nanomaterials (NMs) occurs through the intentional use of nano-agrochemicals, incidental contamination from industrial-waste release, irrigation with wastewater and gray water, or amendment with NM-loaded sludge. Although there are several reports about the effects of NMs in terrestrial plants, there is still a lack of knowledge about the effects of NMs in crop plants and their edible portions.

Among the large list of produced NMs, it is estimated that 34,000 tons of ZnO NMs are produced yearly. Due to their growing applications in cosmetics and personal care products, there is a high possibility that the ZnO NMs …

Synthesis And Application Of Photoreactive Collagen Peptides, And Antiparasitic Agents, Alfredo Ornelas

Open Access Theses & Dissertations

Since the introduction of solid phase peptide synThesis in 1963, peptides and post-translationally modified peptides can be conveniently synthesized in the chemistry laboratory. In the past decade, there has been a remarkable increase in bioactive peptide research and the therapeutic peptide market value is expected to hit $25 billion this year. Peptides can also provide structural and biological functions and have emerged as promising novel biomaterials in tissue engineering. Here we will describe three different projects, which deal with different aspects of peptide chemistry, i.e. synthetic method development, exploration of new peptide biomaterials, and the use of cell penetrating peptides …

Integrated Immunoassays On Paper/Polymer Hybrid Microfluidic Devices For Low-Cost Detection Of Disease Biomarkers, Sanjay Sharma Timilsina

Open Access Theses & Dissertations

Infectious diseases and cancers have been the major cause of global death and disability causing a significant impact on global health and economies. Enzyme-linked immunosorbent assay (ELISA) is one of the most widely used laboratory diagnostic methods for infectious diseases and cancer. ELISA detects proteins based on their binding to immobilized antibodies or antigen. Even though most ELISAs performed today in 96-well plates are well suited for high throughput assays, performing ELISA in low-resource settings is limited by several factors, such as long incubation time, large volumes of precious reagents, and well-equipped laboratories. Herein, we have developed multiple simple, miniaturized …

Photo-Induced Charge Transport In Graphene And Semiconducting Wse2 Integrated With Zero-Dimensional Materials For Enhancing Optoelectronic Device Characteristics, Srishti Chugh

Open Access Theses & Dissertations

Two-dimensional (2D) materials encompass a diverse array of properties from the metallic-like character of graphene to the semiconducting nature of many of the transition metal dichalcogenides (TMDCs) such as tungsten diselenide (WSe2). These materials exhibit intriguing interactions with incoming radiation which makes them interesting for electronics and optoelectronics, especially given the high electron mobility and the ballistic nature of the electronic transport under certain conditions. In particular, the semiconducting TMDCs, such as WSe2, express an indirect-to-direct optical transition with scaling from the bulk to monolayers. Despite the enhanced optical absorption characteristics of monolayer WSe2 stemming from its direct band gap, …

Insights Into The Interaction Of Copper Oxide Nanopar-Ticles With Sweetpotato (Ipomoea Batatas (L.) Lam.): The Role Of Lignin On Copper Uptake And Translocation, Nestor Javier Bonilla Bird

Open Access Theses & Dissertations

Sweetpotato [Ipomoea batatas (L.) Lam.] is widely cultivated in many countries worldwide. The world production of sweetpotato is around 127 billion tons and it is ranked seventh in the world as a staple food. After harvesting, sweetpotato storage roots are treated with fungicides to prolong shelf life. Lignin plays an important role in the conservation of the storage roots. One of the practices to activate the lignification pathway is called “curing process.” The roots are placed under 80% relative humidity at a temperature of 29 ºC for a period of 7 to 15 days, followed by a cooling period at …

Chemistry Goes Green - Experimental Determination Of Pka Values And Metal Binding For Biomolecular Compounds Using 31p Nmr Spectroscopy, R.A. Baker, C.D. Tatko, P.J. Tubergen, M.A. Swartz

University Faculty Publications and Creative Works

1. Research was conducted at UNC-CH for the spring/summer semesters of 2015
2. The following publications were obtained using methods and data from the sabbatical period, though not on the anticipated timeline

Swartz, M.A.*; Tubergen, P.J.*; Tatko, C.D.; Baker, R.A. (2018) “Experimental Determination of pKa Values and Metal Binding for Biomolecular Compounds Using 31P NMR Spectroscopy” Journal of Chemical Education, 95, 1, 182-185.

The proposed work was the bulk of all time used during the sabbatical period. However, this particular research program proved to be extraordinarily complicated. Sophisticated technology was required to support this work that is not available at …

Catalytic Oxidation Of Methane Over Alumina Supported Palladium Oxides, Jacqueline Michelle Mcguire

Theses and Dissertations

The objectives of this research include development and characterization of alumina supported palladium oxide catalysts for low temperature catalytic oxidation of methane. The catalysts were prepared by various methods and then characterized and screened to select the best catalyst for further studies. A 5% (wt/wt) Pd/y-AhCb catalyst prepared by an improved vortex-assisted incipient wetness method showed the best activity of 94% (mol/mol) methane conversion at 325 °C. The active surface species was found to be PdO and Pd native oxides (PdNtv) as confirmed by X-ray Photoelectron Spectroscopy and activity studies. The y-AhCb support played an integral role in the formation …

Antibiotic Effects Of Dimethyl Sulfoxide And Synthetic Polyphenols On E. Coli Cells, Camila Cardenas

Theses and Dissertations

There is increasing interest in polyphenols due to their potential medicinal and antibiotic applications. Naturally occurring polyphenols, such as curcumin, have garnered tremendous attention. However, synthetic polyphenols commonly used in biochemistry experiments have not been sufficiently explored. The purpose of this study is to determine the effect of dimethyl sulfoxide on the cellular uptake of synthetic polyphenols. Three synthetic polyphenols (Phenol Red, Congo Red, and Bromophenol Blue) were tested for their antibiotic properties and compared to the antibiotic activity of curcumin. Our results show that phenol red does not interact with the bacterial membrane even in the presence of 30% …

Development And Evaluation Of Post-Production Oxygenation Techniques For The Augmentation Of Biochar, Matthew David Huff

Chemistry & Biochemistry Theses & Dissertations

Biochar is the carbon rich solid by-product of biomass pyrolysis. Interest in biochar can be broken down to several main categories: use as a carbon sequestration agent, use as a medium for the removal via adsorption of unwanted materials in wastewater, and as a soil amendment for the increase of cation exchange capacity (CEC). In order to generate a biochar which is stable enough for carbon sequestration, higher temperature pyrolysis must be used in order to ensure a lower O:C ratio in order to increase the half-life of biochar in soil. This dissertation addresses the evaluation of biochars made from …

Structure Of The Picornavirus Replication Platform: A Potential Drug Target For Inhibiting Virus Replication, Meghan Suzanne Warden

Chemistry & Biochemistry Theses & Dissertations

Picornaviruses are small, positive-stranded RNA viruses, divided into twelve different genera. Members of the Picornaviridae family cause a wide range of human and animal diseases including the common cold, poliomyelitis, foot and mouth disease, and dilated cardiomyopathy. The picornavirus genome is replicated via a highly conserved mechanism involving a presumed cloverleaf structure located at the 5’ noncoding region of the virus genome. The 5’ cloverleaf consists of three stem loops (B, C, and D) and one stem (A), which interact with a variety of virus and host cell proteins during replication. In this dissertation, human rhinovirus serotype 14 (HRV-14) SLB …

Computational Investigation Of Energetic Materials: Influence Of Intramolecular And Intermolecular Interactions On Sensitivity, Ashley Lauren Shoaf

Chemistry & Biochemistry Theses & Dissertations

The development of novel high energy density materials (HEDMs) with superior energetic properties depends on characterizing how and why detonation occurs. Detonation is highly energetic and a nearly instantaneous process, making experimental studies challenging; thus, computational modeling through density functional theory (DFT) and molecular dynamics (MD) can be used to propose weakened, or activated, bonds that break to initiate explosive decomposition, termed trigger bonds. Bond activation is characterized by the Wiberg bond index (WBI), a measure of interatomic electron density. Trigger bonds in HEDMs are commonly found in explosophores, functional groups that contribute to energetic potential such as X-NO_{2 …}

Synthesis And Characterization Of Glycolipids, Glycoclusters And Glycomacrocycles, Anji Chen

Chemistry & Biochemistry Theses & Dissertations

Low molecular-weight gelators (LMWGs) are a fascinating and interesting class of compounds that can self-assemble and form supramolecular structures in appropriate solvents. The gelators form fibrous networks which entrap the solvent and result in a supramolecular gel. Carbohydrate-derived LMWGs are especially useful since they are more likely to be biocompatible and biodegradable. Dendritic gelators are branch-shaped molecules with precise molecular weight that are between small molecules and polymer gelators. Glycoclusters with sugar moieties at the periphery of the molecules are important classes of bioactive compounds due to the multivalency effect. Lower generation glycoclusters are relatively small branched systems that have …

Synthesis Of New Bodipy Analogs, John Dilyard

Williams Honors College, Honors Research Projects

This report examines the synthesis of new ligands based upon dipyrazolylmethane and diindazolylmethane. The goal of these modifications is to increase the acidity of the proton on the methyl carbon to allow for deprotonation. The ligands synthesized were dipyrazolylphenylmethane and diindazolylphenylmethane, as well as modifications of the latter. The products were analyzed by NMR spectroscopy and one crystal structure was obtained of diindazolylphenylmethane.

Interfacial Corrosion Of Copper And The Formation Of Copper Hydroxychloride, Mary Teague, Shengxi Li, Hongbo Cong

Williams Honors College, Honors Research Projects

Electrical circuitry is an industry, among many others, heavily using the element of copper. Ensuring the mechanical integrity of Cu is crucial, especially in salt environments, for the multifaceted composition of circuits. 4N NaCl solution (equilibrium concentration in ~84% RH) simulated this three-phase system. Rectangular Cu samples were partially immersed in both ambient and continuous lab air sparging atmospheres to understand waterline corrosion of the metal. Open circuit potentials (OCP) were continuously taken during the immersion testing for a maximum of 5 days. A scanning electron microscopy (SEM) equipped with an energy dispersive X-ray spectrometer (EDS), Raman spectroscopy, and 3-D …

Tandem Mass Spectrometry (Ms/Ms) For Determination Of Architecture Of Synthetic Polymers, Shoumik Saha

Williams Honors College, Honors Research Projects

Tandem Mass Spectrometry (MS/MS) was used to determine the architecture of synthetic polymers and they are difluorene-N₃, 3-difluorene-N₃ and VPOSS-3-difluorene. VPOSS materials usually exhibit electrochemical properties and the research was performed to determine their accurate structure and to provide evidence of their proper synthesis. The compounds were mixed with a matrix solution, DCTB, and a silver salt to enable proper protonation. The solvent mixture was on a MALDI plate and then put into the mass spectrometer. The mass spectrum generated was analyzed and each fragment was identified to structures with the synthetic polymers via ChemDraw. Thus, trial …

Carbazole Based Multifunctional Dopamine Agonists And Related Molecules As Potential Symptomatic And Disease Modifying Therapeutic Agents For Parkinson’S Disease, Asma S.Mohamed Elmabruk

Wayne State University Dissertations

Parkinson’s disease (PD) is a progressive neurodegenerative disease that develops from gradual depletion of dopamine (DA) and dopaminergic neurons in the substantia nigra pars compacta (SNc) with the accumulation of intraneuronal proteinaceous matter named as Lewy bodies. The four cardinal symptoms associated with PD are tremor, rigidity, bradykinesia, and postural instability. Although the exact mechanism and etiology of PD are not fully understood, several factors have been implicated in the pathogenesis and progression of PD including protein aggregation, oxidative stress, mitochondrial dysfunction, environmental, and genetic factors.

The current therapy of Parkinson’s disease is categorized into four classes: levodopa, DA agonists, …

Synthesis And Evaluation Of Dual-Acting Ligands For Mu Opioid And Neuropeptide Ff Receptors, Kelsey Gabrielle Mcpherson

Electronic Theses and Dissertations

Pain, although subjective, is an unpleasant sensation caused by a noxious stimulus, that effects millions of people every year. Currently, the most frequently prescribed class of analgesics for moderate to severe acute and sometime chronic pain are opioid analgesics, most commonly ?-opioid receptor (MOP) agonists, such as oxycodone, morphine, and fentanyl. Although these drugs provide significant pain relief, they are also associated with unwelcome side effects such as constipation, addiction, physical dependence, respiratory depression, and physiological tolerance that leads to hyperalgesia. Receptor desensitization due to excessive receptor activation by an agonist is but one source of physiological tolerance; it can …

Transplanting A Bacterial Immune System: Determining The Function Of A Novel Crispr System, Riannon Smith, Melena Garrett

Research on Capitol Hill

CRISPR (Clusters of Regularly Interspaced Short Palindromic Repeats) loci and cas (CRISPR-associated) genes provide adaptive immunity (see panel below) in bacteria and have recently been repurposed for genome editing.

Systems are structurally and functionally diverse.

• 2 classes, 6 types, 33 subtypes
• Very few have been studied experimentally
• None of the Type IV systems have been characterized

Metabolomic Analysis Of The Urine And Tissue In Rats Prone To Type 1 Diabetes Using Nmr, Emily Hunt, Bobba Sumedha, James Wolfsberger

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Magnetic Capture Of Mycobacteria For Rapid Diagnostic Assay, James Johnson

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Measuring Islet Sensitivity To Glucose Stimuulated Insulin Secretion In Lew.1wr1 Rat, Helen Gibson

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Analysis Of Interactions Between Caffeine And Berberine Anti-Cancer Drug In Aqueous Solution Using Nmr Spectroscopy, Bethany Kregger, Charity Yarbrough, Grace Springer

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Rapid Diagnostics: Tailoring Nanomaterial For Magnetic Capture Of Pathogenic Bacteria, Melinda Mustain

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

The Huntingtin Protein: Organic Synthesis Of Poly(Glutamine) Through Side Chain Modification Of Poly(Glutamic Acid), Allana Schafer

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Synthesis Of Silica Coated Magnetic Nanoparticles And Quantum Dots For Bioconjuration Of Lectins, V.V.N. Manohar Devarasetty

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Multi-Dimensional Mass Spectrometry For The Characterization Of Glycopolymers, Maria Ganios

Williams Honors College, Honors Research Projects

Several glycopolymers synthesized by Activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP), were characterized by mass spectrometry to elucidate their microstructure and architecture. Analyses were performed using Matrix Assisted Laser Desorption Ionization- Time of Flight/ Time of Flight (MALDI-ToF/ToF) and Electrospray Ionization Mass Spectrometry (ESI-MS) instruments. The linear isopropylidenated glycopolymer (P65B1) analyzed with ESI-MS also was examined with multi-stage mass spectrometry (MSⁿ) using collision induced dissociation (CID) to examine the tetramer parent ion. This glycopolymer was found to be either cyclic or linear (sans end groups) due to the data being fit for both forms …