Chemistry Commons^™

The Kinetic Modulation Of Α - Synuclein Fibrillation And Toxicity By 4-Phenylbutyric Acid, Kristos Awuah Baffour

Graduate Theses/Dissertations

ABSTRACT

The Protein misfolding and aggregation of alpha-synuclein (α-syn) into neurotoxic amyloids underlies the pathogenesis of neurodegenerative diseases such as Parkinson's disease (PD). 4-Phenylbutyrate (PBA), an FDA drug approved for treating urea cycle disorders, has garnered significant attention as a potential chemical chaperone for targeting alpha-synuclein (α-syn) aggregation. Using in vitro assays, we demonstrated that PBA treatment alters the pattern of α-syn aggregation, as evidenced by reduced formation of oligomeric species and its increased susceptibility to proteolytic cleavage under the influence of PBA. Proteinase K assay, surface plasmon resonance, and Nile red studies indicate that PBA interacts with the extensive …

Development Of Functional Plasmonic Nanoceria For The Ultrasensitive Detection Of Ebola Glycoprotein, Carissa A. Sutton

Graduate Theses/Dissertations

Infectious diseases have been increasing in both severity and prevalence, leading to increasing economic burdens and health concerns. Ebola hemorrhagic fever is an infectious disease that is both highly communicable and highly fatal. Current detection methods for the virus have high specificity and sensitivity but have long and/or complicated procedures that do not allow for early virus detection in highly affected areas. Compared to the lengthy procedure of reverse transcription-polymerase chain reaction (RT-PCR), real-time RT-PCR is more time-efficient; however, specificity and sensitivity are reduced. Since early detection of the virus is the only way to increase survival rates, sensitive detection …

Change Of Metal Oxidation State At High Temperature, Impact Of Temperature And Reactive Gases, Yegor Nikitin

Dissertations and Theses

The fundamental understanding of gas-solid reactions enables a wide range of applications to be developed and improved. Specifically, the use of metal-based materials is critical to ensuring robust, safe, and long-term operations. For example, in power systems where boilers are used to generate steam for heat or electricity generation the use of stainless metal alloys is critical to allow high quality steam to be produced in a very harsh environment. Alternatively, in catalysis, the use of metal doped heterogeneous catalysts are essential in achieving selectivity and conversion performance for chemical synthesis to emissions abatement. Typically, these metal alloys must withstand …

Additive-Dependent Regioselective Boracarboxylation Of Alkenes Using Low Valent Copper And Co2, Carly H. Gordon Ph.D.

Graduate Theses, Dissertations, and Problem Reports (ETD)

As a major greenhouse gas, carbon dioxide (CO₂) is an abundant and renewable C₁ feedstock, and developing methods for fixing CO₂ into high-value products is a major interest for the movement of greener chemistry. The boracarboxylation of alkenes provides access to difunctionalized products containing pharmaceutically relevant motifs, including carboxylic acids and boron-containing moieties. Significant work has been done to improve the versatility and efficiency of this methodology, with the recent expansion into a wide variety of terminal alkenes. The use of different phosphine and alkene additives have demonstrated positive effects on reaction rates and productivity, indicating …

Experimental And Chemical Modeling Of Applied Dc Electric Field Induced H2 – Air Axisymmetric Laminar Co-Flow Diffusion Flames With Low Carbon Impurities, Susith Dilshan Pathmasiri Gunamuni Halowitage

Graduate Theses, Dissertations, and Problem Reports (ETD)

The effect of externally applied DC electric fields on flame structure was investigated in a stationary atmospheric axisymmetric laminar H₂–Air flame with less than 100 ppm carbon equivalent impurities. Flame OH chemiluminescence signals were recorded using a UV-sensitive CCD array as a function of voltage (+10 to -10 kV) applied to a stainless-steel ring electrode placed around the burner nozzle. Changes in chemiluminescence signal are reported as a function of electrode height above the burner, airflow, and fuel composition. Significant changes in OH* distributions were observed for voltages below -5 kV. Under optimum conditions, the height of the …

Development Of Lab-On-A-Chip Platforms Incorporating A Novel Acoustic Atomization Induced Pump Based On A Vibrating Sharp Edge Capillary., Balapuwaduge Lihini Tharanga Catherine Mendis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Capillary Vibrating Sharp-edge Ionization device (cVSSI device) was developed by our laboratory with a low cost and an easy fabrication procedure. The generation of small liquid droplets by this technique has been used as an ionization source for mass spectrometry analysis platforms. On usual applications incorporating the cVSSI device a syringe pump was connected to the back end of the vibrating sharp tip capillary to ensure continuous loading of sample into the capillary to sustain the ionization process at the tip end of the vibrating sharp tip capillary. We were able to observe that upon the generation of droplets the …

Room Temperature Decarboxylative Amination Reactions Of Carboxylic Acids, Rabina Basnet

Graduate Theses, Dissertations, and Problem Reports (ETD)

Anilines are important structural motifs present in numerous natural products and pharmaceutically relevant compounds. Among the various synthetic strategies that have been developed, transition-metal-catalyzed cross-coupling reactions represent one of the most commonly employed methods for the formation of anilines. However, these approaches generally require pre-functionalized aryl coupling partners, and the utilization of more readily available, and structurally diverse coupling partners, such as carboxylic acids, would be desirable. Decarboxylative coupling reactions have garnered significant attention as an alternative approach to form new C-N bonds, and substantial progress has been made in this area. Nevertheless, these methods remain limited, with a predominant …

Investigation Of Space Charge Effects On Co2 Electrocatalytic Reduction On Gd-Doped Ceria Via Scanning Kelvin Probe And Model-Based Bayesian Analysis, Alejandro Mejia

Graduate Theses, Dissertations, and Problem Reports (ETD)

In studying novel energy conversion and storage systems, such as high-temperature electrolysis, numerous underlying fundamental physical processes remain unclear or inadequately understood. Among these, the modeling and comprehension of surface reaction mechanisms, coupled with the intricate effects of space‑charge interfaces, remains an unclear and challenging area of research.

The work of this dissertation involves the development of a 2D finite element analysis model, leveraging the robust MOOSE framework from INL. This model, featuring inhomogeneous defect thermodynamics for near-surface chemistry, formulated through Poisson‑Cahn variational theory, has been exploited for studying the electrocatalytic reduction of CO₂ on gadolinia doped ceria. The …

Α-Hydroxy C–H Functionalization Of Alcohols Via Boronic Acid, Hat, Photoredox Triad Catalytic System, Seth Christopher Cowan

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation explores the research that I have conducted in my time at West Virginia University. Most of my work has focused on the development of methods and studies to further understand the α-OH C–H functionalization of alcohols. This work involves a system of catalysts including photocatalysts, HAT catalysts, and boronic acid catalysts. Chapter 1 highlights a background for each of these areas. Photoredox catalysis has been an increasing area of chemistry over the past two decades as this technique can be used to design conditions to form new bonds in a selective manner through the utilization of light energy. …

Nickel-Catalyzed Regioselective Three-Component Coupling Of Phenyl Vinyl Sulfones With Alkynes, Stephen M. Long

Graduate Theses, Dissertations, and Problem Reports (ETD)

Benzene rings are some of the most prevalent motifs found in small molecule drugs with only a few dominant substitution patterns, 1-, 1,2-, 1,4-, and 1,2,4-. Nucleophilic aromatic substitution and electrophilic aromatic substitution are traditional methods for the synthesis of substituted benzenes and are robust and commonly used by chemical manufacturers, which explains in part the observed distribution of substitution patterns. Current methods to access substituted benzenes comprise of transition-metal-catalyzed C-H activation, transition-metal-catalyzed cross-coupling, and aryne chemistry. In general, the present methods require directing/leaving groups in specific positions to proceed, which inherently puts a limitation on substrate scope. Transition-metal-catalyzed [2+2+2] …

Synthesis, Characterization, And Reactivity Studies Of Pyridine Dipyrrolide Iron-Carbene Complexes With Electronically Distinct Carbene Moieties, Jose G. Rodriguez

Graduate Theses, Dissertations, and Problem Reports (ETD)

First, three (^MesPDP^Ph) iron carbene complexes with electronically distinct carbene moieties were synthesized. These transitional iron carbene complexes were first characterized by ¹H nuclear magnetic resonance (NMR) spectroscopy as their spectra showed paramagnetically shifted resonances. Additionally, their respected solid state structures were collected via X-ray diffraction. The two donor/acceptor iron carbene complexes [(^MesPDP^Ph)Fe(C(CO₂Me)(4-FPh) and (^MesPDP^Ph)Fe(C(CO₂Me)(4-MeOPh)] demonstrated a weak Fe-O interaction between the iron center and ester function group while the (^MesPDP^Ph)Fe(IMe) displayed a C_2v symmetric structure in the …

Building Smart Textile Sensors From Bottom-Up: Chemically Precise Self Assembled Materials On Textiles As A Modular Platform For Electroanalysis, Lori-Ann Williams

Dartmouth College Master’s Theses

In this present work, we explore the metallization of textiles and sutures for the development of a wearable portable modular platform technology for non-invasive wound healing monitoring. Currently technology for the metallization of nonconductive materials have been mainly on a 2D surfaces which restricts the bulk metallization of textile surfaces which require specialized equipment and operators which are costly, energy ineffective, and prevents miniaturization. Metallization of nonconductive fabrics are achieved through a conventional electroless deposition of copper nanoparticle species on 3D surfaces to create electrodes. These conductive textiles and sutures were characterized by pXRD, ATR-IR, SEM-EDS, and XPS and were …

Lessons Learned From Laboratory Study And Field Application Of Re-Crosslinkable Preformed Particle Gels Rppg For Conformance Control In Mature Oilfields With Conduits/Fractures/Fracture-Like Channels, Baojun Bai, Thomas P. Schuman, David Smith, Tao Song

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This Paper Surveys the Role of Re-Crosslink able Preformed Particle Gels (RPPG) in Addressing Conformance Challenges within Mature Oilfields. Despite Widespread Preformed Particle Gel (PPG) Application in 15,000+ Wells, their Limitations in Sealing Fractures and Conduits Prevalent in Mature Reservoirs Have Driven the Development of RPPG Formulations. Synthesized in Various Sizes from Micrometer to Millimeter Levels, These Environmentally Friendly RPPGs Are Tailored for Diverse Reservoir Conditions. Findings Showcase the Successful Laboratory-Scale Creation and Upscaling of RPPG Products, Offering Adaptability to Temperatures from 20 to 175°C, Customizable Sizes, Swelling Ratios (5 to 40 Times), and Re-Crosslinking Times Spanning Minutes to Days. …

Novel Re-Crosslinkable Preformed Particle Gels (Rppg) For Parent- And Infill-Well-Fracture Interactions Mitigation, Xiaojing Ge, Adel Alotibi, Ahmed Al-Hlaichi, Yanbo Liu, Tao Song, Junchen Liu, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Hydraulic fracturing treatments in unconventional infill (or "child") wells can be significantly affected by depletion from existing parent-well, resulting in asymmetrical fracture growth. These issues may lead to excessive load-water production, proppant deposition, casing deformation in the parent well, and unbalanced stimulation of infill wells. To mitigate these effects, various strategies have been proposed, including the use of far-field diverters in child wells and repressurization of parent wells. Additionally, an increasingly popular strategy involves injecting near-wellbore diverters to temporarily plug entry points into the parent wellbores during frac operations on infill wells. To achieve better application, a novel low-cost, self-degradable, …

Self-Quenching Of Carbon Monoxide In The Presence Of Noble Gases, Madeline V. Hinkle

Honors Theses

Precise rate coefficients for the vibrational relaxation pathways of CO(v)-CO in the presence of Ar and Kr have been determined through the work of this thesis. This work was motivated by the need to find a more cost-effective alternative to using xenon as a bath gas, which has increased significantly in price in the past few years. Similar experiments within this lab at Bucknell have been conducted in the past using argon, which can be used in the same manner as xenon but comes at a much lower price, but the experiments yielded inferior results compared to those using xenon. …

Computational Study Of Proton Transfer At Transition Metal Hydrides, Megan Ford

Honors Theses

Energy storage in the bonds of common chemical feedstocks is an attractive solution to the unreliability of wind and solar power due to its long term efficiency and easy recoverability. Energy is stored by reducing chemicals like ammonia, formic acid, and hydrogen, the reaction of which is dependent on a catalyst. To catalyze the reaction, the catalyst undergoes a slow proton transfer (PT) step to form what is known as a metal hydride. The sluggish kinetics of this step lower the effectiveness of the catalyst, and therefore must be better understood in order to improve the efficiency of energy storage …

Aggregation And Oligomerization Characterization Of Ss-Lactoglobulin Protein Using A Solid-State Nanopore Sensor, Mitu C. Acharjee, Brad Ledden, Brian Thomas, Xianglan He, Troy Messina, Jason Giurleo, David Talaga, Jiali Li

Physics Faculty Publications and Presentations

Protein aggregation is linked to many chronic and devastating neurodegenerative human diseases and is strongly associated with aging. This work demonstrates that protein aggregation and oligomerization can be evaluated by a solid-state nanopore method at the single molecule level. A silicon nitride nanopore sensor was used to characterize both the amyloidogenic and native-state oligomerization of a model protein ß-lactoglobulin variant A (βLGa). The findings from the nanopore measurements are validated against atomic force microscopy (AFM) and dynamic light scattering (DLS) data, comparing βLGa aggregation from the same samples at various stages. By calibrating with linear and circular dsDNA, this study …

A Simple, Inexpensive Alkaline Method For Bacterial Dna Extraction From Environmental Samples For Pcr Surveillance And Microbiome Analyses, Abdulkarim Shwani, Bin Zuo, Adnan Alrubaye, Jiangchao Zhao, Douglas D. Rhoads

Poultry Science Faculty Publications and Presentations

DNA extraction for downstream molecular diagnostic applications can be an expensive, time-consuming process. We devised a method to quickly extract total bacterial DNA from environmental samples based on the sodium hydroxide lysis of cells with or without capture by magnetic beads for subsequent PCR or quantitative PCR. The final DNA extraction method using NaOH is extremely low-cost and can be completed in as little as 10 min at room temperature with dilution, or the DNA can be further purified using silica-coated paramagnetic beads. NaOH extraction was effective for Gram-negative and Gram-positive bacteria in samples from air, soil, sewage, food, laboratory …

Wildfire Effects On The Fate Of Deposited Nitrogen In A Boreal Larch Forest, Weili Liu, Jiaxing Zu, B. Liu, Lin Qi, Wei Huang, Yunting Fang, Jian Yang

Earth and Environmental Sciences Faculty Publications

The effects of nitrogen (N) deposition on forests largely depend on the ecosystem N status and the fates of deposited N. Boreal forests are typically N-limited ecosystems and are considered to be more efficient in retaining deposited N relative to temper- ate and tropical forests. As a primary disturbance in boreal forests, wildfires may alleviate N limitation in the burned ecosystem and increase mineralization, resulting in the altered outcomes of the N deposition.

Illuminating Function And Enabling Inhibition At The Protein-Membrane Interface Of Glutathione Peroxidase 4., Courtney L. Labrecque

Theses and Dissertations

Membrane proteins act as gateways to cells and are responsible not only for signaling, lipid transport, and cellular homeostasis, but they are also integral in disease pathologies. One class of membrane proteins, peripheral membrane proteins (PMPs), reside in aqueous compartments of the cell until they are recruited to the membrane to perform their function. Glutathione peroxidase 4 (GPx4) is a PMP enzyme responsible for engaging the membrane and reducing lipid hydroperoxides, thereby preventing cellular death via ferroptosis. Due to its central function surrounding ferroptosis, GPx4 is an interesting drug target that has recently gained interest for inflammatory diseases as well …

An Investigation Of The Correlation Between Polymer Solution Entanglement And Electrospun Polycaprolactone Fiber Mechanics, Manasa Sujatha Rajeev

Honors Theses

The aim of this study was to determine the role of entanglement in the mechanical properties of electrospun polycaprolactone (PCL) fibers. PCL is a useful polyester due to its favorable properties such as its biocompatibility and biodegradability. Multiple concentrations of PCL were dissolved in a 3:1 acetic to formic acid solvent. Fibers were formed using an electrospinning technique. Entanglement is a required parameter to produce fibers, thus the number of entanglements per polymer (ne) was calculated, as well as the corresponding concentrations. Smooth continuous fibers were found to form between 13 w/v% and 17 w/v%. Mechanical analysis, such as three-point …

The Surface Chemistry And Binding Interactions Of Lignin With Polymer-Encapsulated Gold Nanoparticles Acting As Model Microplastics, Oluwaseun Ayodeji Akinsola

All Master's Theses

This study investigates the surface chemistry and molecular-level interactions between lignin, a special type of natural organic matter, and polymer-capped gold nanoparticles, shedding light on the strength of adsorption between lignin and nanoscale polymer surfaces. Specifically, the study presents a variety of nanoscale polymer surfaces displaying different charged functional groups, using layer-by-layer assembly of three polyelectrolytes (polyallylamine hydrochloride (PAH)), polyacrylic acid (PAA), and poly(diallyldimethylammonium chloride (PDADMAC)) on 90 nm citrate-stabilized gold nanoparticles (AuNPs). This approach provides a library of polymer-encapsulated AuNPs for investigating the binding interactions of lignin to nanoscale polymers via spectroscopic techniques. ζ-potential, dynamic light scattering (DLS), …

Roles Of Reactants And Catalysts For Suzuki C-C Cross-Coupling Reaction Using Molecular Volcano Plots And Big-Data Analysis, Kwanchanok Kaewkwan

Chulalongkorn University Theses and Dissertations (Chula ETD)

The Suzuki carbon–carbon cross-coupling reaction is a well-known method for forming carbon–carbon bonds, catalyzed by transition metal complexes. Molecular volcano plots have been used to predict promising catalysts. While previous studies focused mainly on thermodynamic insight, with limited focus on kinetics, this work examines the influence of catalysts and reactants on catalytic activity by incorporating kinetic energy profiles. DFT calculations were performed to evaluate free energies of catalytic states, establish linear scaling relationships, and construct volcano plots. This study employed nickel and palladium complexes with five different ligands as catalysts, reacting with twenty-five substrates. Results show that catalysts have a …

Development Of Biosensors For Detection Of Human Papillomavirus Type 16 Dna, Panon Tungkunaruk

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation aims to develop two unconventional methods for the detection of a high-risk, cancer-causing human papillomavirus type 16 (HPV16) on miniaturized platforms for point-of-care testing (POCT). The first part focuses on a direct detection of HPV16 double-stranded DNA (dsDNA) using the non-self-pairing pyrrolidinyl peptide nucleic acid (acpcPNA) pair on a paper-based substrate coupled with fluorescence and electrochemical dual detections using a DNA-binding dye in a single device. The acpcPNA pair can perform double duplex invasion into dsDNA by hybridizing with each strand of DNA in the same region without the requirement of denaturing dsDNA to single-stranded DNA (ssDNA) before …

Development Of Electrochemical Sensor Based On Molecularly Imprinted Polymer For Determination Of Roxarsone, Pitranan Kunthanasap

Chulalongkorn University Theses and Dissertations (Chula ETD)

Roxarsone (ROX), a growth enhancer in poultry and swine, has the potential to improve weight gain and prevent coccidiosis. Excessive use of ROX may lead to its accumulation in animal tissues, potentially contaminating food products and posing health risks to humans through consumption. This research aims to develop an electrochemical sensor based on a magnetic screen-printed graphene electrode (mSPGE) modified with a highly selective molecularly imprinted polymer (MIP) for the determination of ROX with enhanced sensitivity and selectivity. Typically, an applied magnetic field at the mSPGE could accelerate mass transport at the electrode surface through the magnetohydrodynamic (MHD) effect, leading …

Flow Accelerated Corrosion In Economizer Tubes Of A Heat Recovery Steam Generator Using Computational Fluid Dynamics, Phuris Khunphakdee

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study investigates the effects of operating and harp design parameters on flow accelerated corrosion (FAC) using CFD, based on a real case from a modern heat recovery steam generator (HRSG) where severe FAC occurred in an economizer harp after six years of service. Preliminary investigation found that contributions for this case include the construction material, which is carbon steel, the operating temperature range that close to FAC favourable temperature (150 °C), reduced water and disturbed flow geometry. Comparison of shear stress and wall thickness profiles confirmed that FAC is mass transfer dominated, driven by flow acceleration and recirculation near …

Aza-Piancatelli And Friedel-Crafts Reactions Under Microdroplet Conditions, Phanomsak Yukhet

Chulalongkorn University Theses and Dissertations (Chula ETD)

The development of sustainable, catalyst-free synthetic methodologies represents a significant advance in modern organic chemistry, which offers environmentally benign alternatives to conventional protocols that often rely on metal catalysts or harsh reagents. This dissertation presents two complementary studies to explore and establish novel catalyst-free synthetic strategies in both microdroplet and bulk solution phases and highlight their potential applications, mechanistic features, and practical limitations. The first part of this work investigates the rearrangement of furfural with secondary amines to yield 4,5-diaminosubstituted cyclopentenones (4,5-DCPs) within the unique reaction environment of electrospray-generated charged microdroplets. The reaction is proposed to proceed via a Stenhouse …

Hydrogen Molecule Adsorption On Heptazine Carbon Nitride Nanosheet Decorated Rh, Ir, Pd, And Pt Elements For Hydrogen Storage Application, Piyawat Amornthatri

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, the hydrogen storage and sensing potential of pristine and metaldecorated heptazine carbon nitride nanosheets (hg-C3N4-NS) was investigated using density functional theory (DFT) calculations. Decoration with platinum-group metals-Rh, Ir, Pd, and Pt-was examined in two stable configurations: an off-center coordination site (Group 1) and a pore-center site (Group 2). Hydrogen adsorption was studied stepwise from one up to three H2 molecules per system to simulate the natural accumulation process. The results revealed that pristine hg-C3N4-NS exhibits only weak physisorption, whereas metal decoration markedly enhances adsorption strength. Among all systems, Ir-hg-C3N4-NS1 and Rh-hg-C3N4-NS1 showed the most exothermic adsorption energies …

The Effect Of Solvent Identity And Hydride-Donor On The Reduction Of Co2 Into Useful Fuels, Abigail Mcentire

Honors Theses

One possible strategy for decreasing CO2 emissions is through electrocatalytic reduction reactions to convert the CO2 back into combustible fuels , such as methane or methanol. However, it can be challenging to control the reaction to select one of these useful fuels as opposed to carbon monoxide or formate. Our strategy is to investigate a specific hydride donor and solvent combinations for which the reaction favors conversion to methanol. It was found that in acetonitrile , several hydride donors were capable of selective reduction of CO2 to the methanol oxidation state.

Exploration Of Sulfonamides And Benzothiazoles As Peptide-Based Cleavable Linkers, Abigail Dalton

Honors Theses

Cleavable linkers have demonstrated great potential in various applications of medicinal organic chemistry, such as in modern therapeutic development. Linkers are stable compounds that cleave in specific conditions to release molecular cargo. We have developed cleavable linkers based on nucleophilic aromatic substitution reactions on sulfonamide and benzothiazole substrates in small molecule and in peptide studies. Sulfonamides, commonly with an electron-withdrawing group, reacted in high conversion of starting material to the sulfide product in small molecule studies, but was unable to successfully cleave the sulfonamide linker on peptide in mild conditions. Next, a benzothiazole sulfone substrate was analyzed and optimized in …