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Characterization And Quantification Of Covalent Modification Of Proteins Using Mass Spectrometry, Pratikkumar N. Rathod 2018 The Graduate Center, City University of New York

Characterization And Quantification Of Covalent Modification Of Proteins Using Mass Spectrometry, Pratikkumar N. Rathod

All Dissertations, Theses, and Capstone Projects

Identification and characterization of various post-translational modifications of protein is a key to understanding many unknown cellular processes. In the last few decades, mass spectrometry has evolved as an essential and effective analytical tool for qualitative and quantitative analysis of proteins. In this research, we have developed a novel MALDI-MS2 based quantification method for Desmosine and Isodesmosine, which served as cross-linking amino acids of elastin, in order to measure the elastin degradation in the body. This is the first quantification method that not only illustrates the potential of MALDI-Ion Trap MS2, but also improvement over the current LC-MS ...


Determination Of Polar Solvents By Static Headspace Extraction – Gas Chromatography (She-Gc), Michael Sithersingh 2018 Seton Hall University

Determination Of Polar Solvents By Static Headspace Extraction – Gas Chromatography (She-Gc), Michael Sithersingh

Seton Hall University Dissertations and Theses (ETDs)

ABSTRACT

The term “headspace” is defined as the vapor that forms above or around a liquid or solid sample in a closed container. Usually, the vapor is above the liquid or solid at the top of the container, hence the term headspace. Headspace sampling is a method for separating volatile materials that may be extracted from a more solid sample matrix and then analyzed using gas chromatography. Headspace extraction refers to the collection and analysis of the vapor phase in the container. The Static Headspace Extraction – Gas Chromatography (SHE-GC) technique has been used since the early days of Gas Chromatography ...


Immobilization Of Gold Nanoparticles On Nitrided Carbon Fiber Ultramicroelectrodes By Direct Reduction, George Affadu-Danful 2018 East Tennessee State University

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 ...


Comparing Laser Assisted Pulling And Chemical Vapor Deposition Methods In The Fabrication Of Carbon Ultramicro- And Nanoelectrodes, Theophilus Neequaye 2018 East Tennessee State University

Comparing Laser Assisted Pulling And Chemical Vapor Deposition Methods In The Fabrication Of Carbon Ultramicro- And Nanoelectrodes, Theophilus Neequaye

Electronic Theses and Dissertations

Ultramicroelectrodes (UMEs) (limiting dimensions <~25 μm) and nanoelectrodes (<~100 nm) exhibit enhanced electrochemical properties compared to macroscopic electrodes. Their small sizes and enhanced properties make them well-suited for various interesting and important applications such as measuring redox-active species in nonaqueous solvents, studying intermediates of fast electrochemical reactions, and investigating electrochemical and electrocatalytic properties of single nanoparticles. While UMEs are commercially available, nanoelectrode fabrication is still largely confined to research labs. Various methods for constructing nanoelectrodes have been reported and continue to be developed, but most require considerable expertise, and comparisons between different fabrication processes are lacking. In this work, a comparison of laser-assisted pulling and chemical vapor deposition (CVD) methods of electrode fabrication is made with the aim of optimizing production of carbon nanoelectrodes for single nanoparticle electrochemical measurements. By examining effects of pulling parameters, post-pulling treatments, and CVD processing, electrodes as small as ~50 nm were successfully produced.


Hydrolysis Of Cellulose And Biomass Using Blue Molybdenum, Farouk Awudu 2018 East Tennessee State University

Hydrolysis Of Cellulose And Biomass Using Blue Molybdenum, Farouk Awudu

Electronic Theses and Dissertations

Hydrolysis of cellulosic biomass is an important and ongoing subject of research due to generating precursors for biofuel synthesis. This work involves hydrolysis of microcrystalline cellulose and Arundo donax to glucose. Methods for acid hydrolysis include the use of sulfuric acid, phosphomolybdic acid, blue molybdenum using low concentrations at 40-100 °C. For comparison purposes, enzymatic hydrolysis was also carried out using cellulase. Products were quantified by measuring total organic carbon and reducible sugars using dinitrosalicylic acid. Use of phosphomolybdic acid, blue molybdenum and sulfuric acid even at 6.0 M did not increase the amount of glucose compared to using ...


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

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 ...


Novel Relative Spontaneous Ignition Temperature Determination Using Carbon Dioxide Onset With Sta/Ir, Antonio David Trevino 2018 Stephen F. Austin State University

Novel Relative Spontaneous Ignition Temperature Determination Using Carbon Dioxide Onset With Sta/Ir, Antonio David Trevino

Electronic Theses and Dissertations

Simultaneous thermal analysis, coupled with infrared spectroscopy (STA/IR), was utilized to monitor the evolution of gaseous products during the thermal degradation of samples from Triadica sebifera (Chinese tallow), Ligustrum sinense (Chinese privet), and Ilex vomitoria (yaupon) plants. Identification of carbon dioxide was successful with a spectral match of 90.2 percent and further used in the determination of relative spontaneous ignition temperature, or RSIT. The RSIT value during the growing season for Chinese tallow, Chinese tallow stem, Chinese privet, and Yaupon were 208.4°C, 250.3°C, 210.1°C, and 232.3°C respectively. During the dormant ...


Steric Effects Of Alkyl Ammonium Salts On The Combustion Of Exchanged Smectite Clays, Celeste A. Keith 2018 Stephen F. Austin State University

Steric Effects Of Alkyl Ammonium Salts On The Combustion Of Exchanged Smectite Clays, Celeste A. Keith

Electronic Theses and Dissertations

Bomb calorimetry was explored as a new method for determining the cation exchange capacity (CEC) of clays. Smectite clays were modified with several alkyl ammonium salts varying in number of carbons and the spatial orientation of the carbons about the central nitrogen atom. The clays used, standards purchased from the Source Clay Repository, have CECs of 44, 80, 88, and 120 meq/100 g. Theoretically, the combustion energy of the organo-clays should be approximately the same for each salt. Any differences in energy would be due to the different structures of the salts and how they are oriented in the ...


Removal Of Pb2+ Ions From Consuming Water Using A Fabricated Water Filter For Home Use, Pantaree Sodkhoksoong, Papidchaya Chanpong, Thunyarus Rodsawatchuchoke 2018 Mahidol Wittayanusorn School

Removal Of Pb2+ Ions From Consuming Water Using A Fabricated Water Filter For Home Use, Pantaree Sodkhoksoong, Papidchaya Chanpong, Thunyarus Rodsawatchuchoke

The International Student Science Fair 2018

Lead contamination in water is one of the worldwide concerned environmental problems. For example, lead leaking from pipe corrosion and solder has been found contaminated in consuming water in many U.S. areas. The uncontrolled release of effluents containing lead from various industries has also caused lead-contaminated water in Thailand. Exposing to lead-contaminated water can lead to serious symptoms (e.g. fatigue, headaches, abdominal pain, irritability, depression, and seizures) or even death. Therefore, the elimination of lead ions (Pb2+) from consuming water or from effluents before releasing into the environment is necessary. The selection of adsorbents and the fabrication ...


Synthesis And Characterization Of Organically Modified Hectorites For Sequestration Of Pfaas From Contaminated Drinking Water, Alexandra Pagano 2018 Union College

Synthesis And Characterization Of Organically Modified Hectorites For Sequestration Of Pfaas From Contaminated Drinking Water, Alexandra Pagano

Honors Theses

Perfluoroalkyl Acids (PFAAs), a family of industrial chemicals, are found in household products such as pizza boxes, microwave popcorn bags, and non-stick pans. PFAAs of different carbon chain lengths and ionic head groups exist, such as PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid). Used without regulation in industry for decades, PFAAs only recently became recognized as contaminants of emerging concern, since they are bioaccumulative in organisms, persistent in the environment, and toxic. PFAAs are known to accumulate in the blood, liver and kidneys, and drinking water contaminated with PFAAs has been linked to certain types of cancer. Therefore, it ...


Analysis Of Metallic Components Of Gsr From Various Types Of Ammunition And Firearms Utilizing An Sem-Edx, Jenna A. Campbell 2018 Duquesne University

Analysis Of Metallic Components Of Gsr From Various Types Of Ammunition And Firearms Utilizing An Sem-Edx, Jenna A. Campbell

Graduate Student Research Symposium

Gunshot residue (GSR) is a chemical reaction that occurs when a firearm is discharged, which emits a cloud of gases from the barrel of the gun. It consists of both the burned and unburned propellant and primer components. These components are either organic or inorganic in nature, respectively. The organic components are located in the gunpowder part of the bullet, while the inorganic components are located in the primer part of the bullet. The primer consists of lead, barium, and antimony. These elements are considered heavy metals. Additionally, lead, barium, and antimony are the three key elements found in the ...


Assessment Of The Viability Of Microwell Plates As Sample Holders For Analytical Excitation-Emission Spectroscopy Of Polyaromatic Hydrocarbons In 75% Ethanol, Lauren M. Ridley-Hoffman 2018 Seton Hall University

Assessment Of The Viability Of Microwell Plates As Sample Holders For Analytical Excitation-Emission Spectroscopy Of Polyaromatic Hydrocarbons In 75% Ethanol, Lauren M. Ridley-Hoffman

Seton Hall University Dissertations and Theses (ETDs)

Polyaromatic hydrocarbons (PAHs) in the environment are a significant concern as many compounds in this class are potential carcinogens. PAHs resulting from petroleum spills can contaminate natural waters and the products obtain from them (fish and fish products in particular). Previous studies by Pena, et. al. on ethanolic extracts of organs from menhaden captured in the vicinity of the Deepwater Horizon (Macondo oil well) spill have shown that fluorescence excitation spectroscopy is a useful technique for detecting the presence of PAH metabolites and fluorescent vitamins. The study has also concluded that previous methods for analyzing PAHs using fluorescence spectroscopy used ...


Assessment Of Energetic Heterogeneity Of Reversed-Phase Surfaces Using Excess Adsorption Isotherms For Hplc Column Characterization, Leih-Shan Yeung 2018 Seton Hall University

Assessment Of Energetic Heterogeneity Of Reversed-Phase Surfaces Using Excess Adsorption Isotherms For Hplc Column Characterization, Leih-Shan Yeung

Seton Hall University Dissertations and Theses (ETDs)

This research is to explore a more general column categorization method using the test attributes in alignment with the common mobile phase components. As we know, the primary driving force for solute retention on a reversed-phase surface is hydrophobic interaction, thus hydrophobicity of the column will directly affect the analyte retention. This research describes a method to determine the column hydrophobicity by the ratio of adsorbed acetonitrile and methanol to water on the column surface using excess adsorption isotherm estimation. An excess adsorption isotherm for a binary mobile phase system represents a competitive interaction of both solvent components with the ...


Extraction And Purification Of (E)-Resveratrol From The Bark Of Maine's Native Spruces, Panduka S. Piyaratne 2018 University of Maine

Extraction And Purification Of (E)-Resveratrol From The Bark Of Maine's Native Spruces, Panduka S. Piyaratne

Electronic Theses and Dissertations

Resveratrol is a plant secondary metabolite which protects plants from pathogenic invasions and acts as a remedial agent against injury, stress, and tissue damage by UV radiation. With its characteristic stilbene structure, resveratrol adopts (E) and (Z) isomeric forms. However, the (E) isomer is the most biologically active and abundant form of resveratrol in nature.

(E)- Resveratrol confers a variety of benefits to human health and well-being. Besides its antioxidant activity, the role of (E)-resveratrol as an anti-inflammatory, anti-aging, cardioprotection, and anticancer agent has been a widely explored research interest. Many plant species including mulberry, peanut, and grape are ...


Fast Identification Of Components Commonly Used In Homemade Explosives By Spectroscopic And Chemometric Methods, Deidre Day Vandenbos, Huggins Msimanga, Christopher Dockery 2018 Kennesaw State University

Fast Identification Of Components Commonly Used In Homemade Explosives By Spectroscopic And Chemometric Methods, Deidre Day Vandenbos, Huggins Msimanga, Christopher Dockery

Master of Science in Chemical Sciences Theses

Homemade explosives (HMEs) have become a global pandemic. This forensic research focuses on developing identification methods that can provide quick, cost effective, non-destructive analysis using portable instrumentation. These capabilities would be invaluable to first responders, military, and security officials to establish an evidentiary link between a suspect and a reference in cases of HMEs, IEDs, arson and environmental contamination.

Modern methods for quick identification of the fuels and oxidant sources used in manufacturing HMEs, include Fourier Transform Infrared (FT-IR) and Raman spectroscopy. Visual confirmation alone, however, is not strong enough to discriminate chemicals with nearly identical spectra, which occurs when ...


Kinetics And Activation Energy Parameters For Hydrolysis Of Acetic Anhydride In A Water-Acetone Cosolvent System, Samson Olowoyo 2018 East Tennessee State University

Kinetics And Activation Energy Parameters For Hydrolysis Of Acetic Anhydride In A Water-Acetone Cosolvent System, Samson Olowoyo

Electronic Theses and Dissertations

The hydrolysis of acetic anhydride is a widely-studied liquid phase reaction studied since 1906. Different approaches have been used to study the kinetics of this reaction. Approaches used by researchers have involved the use of sophisticated experimental set-ups. In this work, the pH technique has been adopted which involves the use of a pH meter to monitor the hydrolysis reaction. Analysis of the hydrolysis reaction has been performed for water/acetone cosolvent systems over a range of temperatures and mole fractions. Eyring analysis was performed under isomole fraction conditions and activation enthalpy, entropy, and Gibbs free energy for hydrolysis of ...


Eyring Activation Energy Analysis Of Acetic Anhydride Hydrolysis In Acetonitrile Cosolvent Systems, Nathan Mitchell 2018 East Tennessee State University

Eyring Activation Energy Analysis Of Acetic Anhydride Hydrolysis In Acetonitrile Cosolvent Systems, Nathan Mitchell

Electronic Theses and Dissertations

Acetic anhydride hydrolysis in water is considered a standard reaction for investigating activation energy parameters using cosolvents. Hydrolysis in water/acetonitrile cosolvent is monitored by measuring pH vs. time at temperatures from 15.0 to 40.0 °C and mole fraction of water from 1 to 0.750. This work utilizes a temperature controlled water bath and a Vernier glass-body pH probe with Vernier Logger Pro 3.10.1 software for automated data collection. Data analysis is used to determine observed kinetic rate constants under the assumption that hydrolysis is a pseudo-first-order reaction. Eyring plots were used to compare activation ...


Development Of Microdialysis Probes In Series Approach Toward Eliminating Microdialysis Sampling Calibration: Miniaturization Into A Pdms Microfluidic Device, Randy Espinal Cabrera 2018 University of Arkansas, Fayetteville

Development Of Microdialysis Probes In Series Approach Toward Eliminating Microdialysis Sampling Calibration: Miniaturization Into A Pdms Microfluidic Device, Randy Espinal Cabrera

Theses and Dissertations

A new microdialysis sampling method and microfluidic device were developed in vitro. The method consisted of using up to four microdialysis sampling probes connected in series to evaluate the relative recovery (RR) of different model solutes methyl orange, fluorescein isothiocyanate (FITC)-dextran average mol. wt. 4,000 (FITC-4), FITC-10, FITC-20, and FITC-40. Different flow rates (0.8, 1.0, and 1.5 µL/min) were used to compare experimentally observed relative recoveries with theoretical estimations. With increasing the number of probes in series, the relative recovery increases and ~100% (99.7% ± 0.9%) relative recovery for methyl orange was obtained ...


Ultrafast Affinity Extraction And High-Performance Affinity Chromatography Applications For Measuring Free Drug Fractions: Interactions Of Sulfonylurea Drugs With Normal And Glycated Human Serum Albumin, Bao Yang 2018 University of Nebraska - Lincoln

Ultrafast Affinity Extraction And High-Performance Affinity Chromatography Applications For Measuring Free Drug Fractions: Interactions Of Sulfonylurea Drugs With Normal And Glycated Human Serum Albumin, Bao Yang

Student Research Projects, Dissertations, and Theses - Chemistry Department

Ultrafast affinity extraction was used with microcolumns containing human serum albumin (HSA) to measure the free fractions of several sulfonylurea drugs in the presence of solution-phase HSA and for the analysis of these drugs at therapeutic levels or determining their binding strengths with this protein. This approach was first used with normal HSA and the drugs glibenclamide, glipizide and glimepiride. This work used both one- and two-dimensional affinity systems based on HSA microcolumns. The first microcolumn was used to extract the free drug fractions in injected drug/protein mixtures. As the retained drug eluted from the first microcolumn, it was ...


Surface Reaction And Diffusion Kinetics In Semiconducting Metal Oxide Film Gas Sensors, Aravind Reghu 2018 University of Maine

Surface Reaction And Diffusion Kinetics In Semiconducting Metal Oxide Film Gas Sensors, Aravind Reghu

Electronic Theses and Dissertations

Chemiresistive metal oxide gas sensors based on materials such as SnO2, ZnO, and TiO2, have been investigated extensively by many researchers for a wide range of applications. The band bending model, based on the surface chemistry of highly reactive ionosorbed species (O2- or O-) and the semiconducting material properties of SnO2, TiO2 and ZnO, adequately predicts the dependence of the change in sensor conductivity (Δσ) as a function of target gas pressure and temperature. However, the band bending model is not applicable to gas sensors based on reducible oxides such as WO3, MoO3 ...


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