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Development And Characterization Of A Paper Based Analytical Device For Heparin Quantification, Carolanne Norris 2018 Otterbein University

Development And Characterization Of A Paper Based Analytical Device For Heparin Quantification, Carolanne Norris

Undergraduate Honors Thesis Projects

Paper-based analytical devices (PAD) have gained popularity in the past ten to fifteen years due to many favorable mechanical properties.1 They have largely been used to analyze small ionic species, such as Na+ and Li+, but little research has been done on their capability of to analyze large polyionic species, for instance the highly sulfonated polysaccharide heparin.2,3 This study explores adaptation of a traditional optode design to a low cost PAD that employs a smartphone as a detector. Throughout the study variables, such as membrane composition, pH, volume of solution, time, addition of a polymer, use of different cell phone …


Part I: Design, Synthesis, And Studies Of Novel Age-Inhibitors And Age-Breakers; Part Ii: Novel Synthetic Methods For Organofluorine Compound, Jatin Mehta 2018 Missouri University of Science and Technology

Part I: Design, Synthesis, And Studies Of Novel Age-Inhibitors And Age-Breakers; Part Ii: Novel Synthetic Methods For Organofluorine Compound, Jatin Mehta

Doctoral Dissertations

"Novel small molecule inhibitors and breakers of advanced glycation end-products (AGEs) have been synthesized and their in vitro inhibitory activities have been studied by 13C NMR, fluorescence, and UV-visible spectroscopy. We have demonstrated that these AGE-inhibitors and AGE-breakers were found to be more effective in their sequestration of AGE intermediates, such as dehydroascorbate (DHA) than the state-of-the art phenacylthiazolium bromide (PTB)-based AGE-inhibitors and AGE-breakers. Citric acid and other polyphenolic antioxidants have substantial AGE inhibitory effects in the D-glucose/leucine or benzylamine Maillard reaction model systems, and thus they are suitable as dietary additives for ameliorating AGE-induced complications.

Organofluorine compounds have …


Characterization Of Solution-Phase Drug-Protein Interactions By Ultrafast Affinity Extraction, Sandya Beeram, Xiwei Zheng, Kyungah Suh, David S. Hage 2018 University of Nebraska–Lincoln

Characterization Of Solution-Phase Drug-Protein Interactions By Ultrafast Affinity Extraction, Sandya Beeram, Xiwei Zheng, Kyungah Suh, David S. Hage

Chemistry Department: Faculty Publications

A number of tools based on high-performance affinity separations have been developed for studying drug-protein interactions. An example of one recent approach is ultrafast affinity extraction. This method has been employed to examine the free (or non-bound) fractions of drugs and other solutes in simple or complex samples that contain soluble binding agents. These free fractions have also been used to determine the binding constants and rate constants for the interactions of drugs with these soluble agents. This report describes the general principles of ultrafast affinity extraction and the experimental conditions under which it can be used to characterize such …


Systems And Methods For Actuating Soft Robotic Actuators, Robert F. Shepherd, Adam Stokes, Stephen A. Morin, Ludovico Cademartiri, Jacob Freake, Rui Nunes, Xin Chen, George M. Whitesides 2018 Brooktondale, NY

Systems And Methods For Actuating Soft Robotic Actuators, Robert F. Shepherd, Adam Stokes, Stephen A. Morin, Ludovico Cademartiri, Jacob Freake, Rui Nunes, Xin Chen, George M. Whitesides

Chemistry Department: Faculty Publications

Systems and methods for providing a soft robot is provided. In one system , a robotic device includes a flexible body having a fluid chamber, where a portion of the flexible body includes an elastically extensible material and a portion of the flexible body is strain limiting relative to the elastically extensible material. The robotic device can further include a pressurizing inlet in fluid communication with the fluid chamber, and a pressurizing device in fluid communication with the pressurizing inlet, the pressurizing device including a reaction chamber configured to accommodate a gas producing chemical reaction for providing pressurized gas to …


Flexible Thin Robotic Actuators, Aaron D. Mazzeo, Stephen A. Morin, Robert F. Shepherd, George M. Whitesides, William B. Kalb 2018 Duenellen, NJ

Flexible Thin Robotic Actuators, Aaron D. Mazzeo, Stephen A. Morin, Robert F. Shepherd, George M. Whitesides, William B. Kalb

Chemistry Department: Faculty Publications

Some embodiments of the disclosed subject matter includes a laminated robotic actuator. The laminated robotic actuator includes a strain-limiting layer comprising a flexible, non extensible material in the form of a sheet or thin film, a flexible inflatable layer in the form of a thin film or sheet in facing relationship with the strain-limiting layer, wherein the inflatable layer is selectively adhered to the strain-limiting layer, and wherein a portion of an un-adhered region between the strain-limiting layer and the inflatable layer defines a pressurizable channel, and at least one fluid inlet in fluid communication with the pressurizable channel. The …


Reductive Cleavage Of Organic Peroxides By Iron Salts And Thiols, Anderw Olson, Abigail J. Jameson, Shiva K. Kyasa, Boone W. Evans, Patrick H. Dussault 2018 University of Nebraska - Lincoln

Reductive Cleavage Of Organic Peroxides By Iron Salts And Thiols, Anderw Olson, Abigail J. Jameson, Shiva K. Kyasa, Boone W. Evans, Patrick H. Dussault

Chemistry Department: Faculty Publications

Despite the low bond strength of the oxygen− oxygen bond, organic peroxides are often surprisingly resistant to cleavage by nucleophiles and reductants. As a result, achieving decomposition under mild conditions can be challenging. Herein, we explore the reactivity of a selection of peroxides toward thiolates, phenyl selenide, Fe(II) salts, and iron thiolates. Peroxides activated by conjugation, strain, or stereoelectronics are rapidly cleaved at room temperature by thiolate anions, phenylselenide, or Fe(II) salts. Under the same conditions, unhindered dialkyl peroxides are only marginally reactive; hindered peroxides, including triacetone triperoxide and diacetone diperoxide (DADP), are inert. In contrast, all but the most …


Integrating Microscale Enzyme And Lectin Reactions Using Nanogel Assisted Capillary Electrophoresis, Srikanth Gattu 2018 West Virginia University

Integrating Microscale Enzyme And Lectin Reactions Using Nanogel Assisted Capillary Electrophoresis, Srikanth Gattu

Graduate Theses, Dissertations, and Problem Reports

Protein glycosylation is one of the most prevalent post-translational modifications which plays an important role in determining the structure, stability, and function of proteins. Changes in glycosylation patterns are a hallmark of cancer and other diseases. Characterizing glycosylation is difficult because these structures vary in their linkage and monomer sequence, which gives rise to vast microheterogenity that could affect the function of the molecule. A novel method using capillary gel electrophoresis by integrating microscale enzymes and lectin reactions in the capillary was developed to verify glycan structure by analyzing monosaccharides. Capillary electrophoresis (CE) improves upon conventional methods of glycan structure …


Development Of Multi-Class Analytical Methods For Agrochemical Contaminants, Sarah Tuck 2018 Department of Chemistry, Cork Institute of Technology, Cork, Ireland.

Development Of Multi-Class Analytical Methods For Agrochemical Contaminants, Sarah Tuck

Theses

In this project, cost-effective multi-class analytical methods were developed to detect a range of antiparasitic, feed additive and pesticide substances in foodstuffs of animal origin. These substances have the potential to enter the food chain through their occurrence as residues either through the animals themselves or other routes e.g. contamination. To ensure the continued safety of food destined for human consumption regulatory control limits have been established for permitted levels of these residues in foods of animal origin. Despite these controls the continued monitoring of foodstuffs is necessary to ensure these limits are not breached and that substances are not …


Enhanced Analysis Of Lignin Dehydrogenation Oligomers Via Mass Spectrometry, Amber Suzanne Bowman 2018 University of Kentucky

Enhanced Analysis Of Lignin Dehydrogenation Oligomers Via Mass Spectrometry, Amber Suzanne Bowman

Theses and Dissertations--Chemistry

Effective analytical techniques need to be developed to characterize the products of lignin degradation experiments to be able to generate renewable products from lignin. Mass spectrometry is an valuable analytical approach for lignin characterizaion, but it is hindered by lignin’s poor ionization efficiency, especially in the positive ion mode. In this work, we attempt to improve lignin’s ionization by utilizing electrospray and laser desorption mass spectrometry coupled with the addition of cations and chemical derivatives. We confronted the ionization problem from both a top-down and bottom-up analytical approach by analyzing synthesized monomers, dimers, and polymers along with natural lignin extracts …


Tandem Mass Spectrometry And Computational Approaches To Elucidate Conformations And N-Glycosidic Bond Stabilities Of Dna And Rna Nucleosides And Mononucleotides, Yanlong Zhu 2018 Wayne State University

Tandem Mass Spectrometry And Computational Approaches To Elucidate Conformations And N-Glycosidic Bond Stabilities Of Dna And Rna Nucleosides And Mononucleotides, Yanlong Zhu

Wayne State University Dissertations

ABSTRACT

TANDEM MASS SPECTROMETRY AND COMPUTATIONAL APPROACHES TO ELUCIDATE CONFORMATIONS AND N-GLYCOSIDIC BOND STABILITIES OF DNA AND RNA NUCLEOSIDES AND MONONUCLEOTIDES

by

YANLONG ZHU

May 2018

Advisor: Dr. Mary T. Rodgers

Major: Analytical Chemistry

Degree: Doctor of Philosophy

The influence of noncovalent interactions with sodium cations on the conformations and energetics of ten DNA and RNA nucleosides as well as two adenine mononucleotides were elucidated via infrared multiple photon dissociation (IRMPD) action spectroscopy experiments and complementary electronic structure calculations. Energy-resolved collision-induced dissociation (ER-CID) experiments of protonated and metal cationized DNA and RNA nucleosides were performed using a Bruker amaZon ETD …


Integrated Immunoassays On Paper/Polymer Hybrid Microfluidic Devices For Low-Cost Detection Of Disease Biomarkers, Sanjay Sharma Timilsina 2018 University of Texas at El Paso

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 …


Oil Dries: A New Absorbent Material For Collection Of Ignitable Liquids From Semi-Porous Material, Jessica Sosa 2018 Eastern Kentucky University

Oil Dries: A New Absorbent Material For Collection Of Ignitable Liquids From Semi-Porous Material, Jessica Sosa

Online Theses and Dissertations

Extraction of an ignitable liquid sample from a semi-porous surface such as concrete is especially difficult. For this purpose, two different solid oil dry absorbent materials, Instazorb and MAXXAbsorb, were researched for use of collection of ignitable liquid samples at a fire scene. These oil dries were spiked with different ignitable liquids (Coleman fuel, gasoline, kerosene, and diesel). Isolation of the ignitable liquid from the oil dry absorbent was accomplished by passive headspace isolation. Data was obtained by gas chromatography coupled with flame ionization detection (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). Chromatograms obtained from both oil dries …


Aqueous Photochemistry Of 2-Oxocarboxylic Acids, Alexis Eugene 2018 University of Kentucky

Aqueous Photochemistry Of 2-Oxocarboxylic Acids, Alexis Eugene

Theses and Dissertations--Chemistry

Atmospheric aerosols affect climate change by altering the energy balance of the atmosphere, and public health due to their variable chemical composition, size, and shape. While the formation of secondary organic aerosol (SOA) from gas phase precursors is relatively well understood, it does not account for the abundance of SOA observed during field measurements. Recently it has become apparent that in-aerosol aqueous chemical reactions likely provide some of the missing sources of SOA production, and many studies of aqueous phase processes are underway.

This work explores the fates of the simplest 2-oxocarboxylic acids, glyoxylic acid (GA) and pyruvic acid (PA), …


Monitoring Infection Of E. Coli By Bacteriophage T7 Through Mass Spectrometry-Based Proteomics, Amy Swayne Schienschang 2018 William & Mary - Arts & Sciences

Monitoring Infection Of E. Coli By Bacteriophage T7 Through Mass Spectrometry-Based Proteomics, Amy Swayne Schienschang

Dissertations, Theses, and Masters Projects

Mass spectrometry-based proteomics has become an important and versatile tool in analytical chemistry, making sense of complex biological samples and shedding light on the intricate proteomes of living organisms. Bottom-up proteomics studies are used to elucidate the changes in gene expression of bacteriophage T7 over the course of infection of Escherichia coli. E. coli cultures were infected with T7, sampled over time, and proteins were isolated and enzymatically digested. Nanoflow liquid chromatography combined with tandem mass spectrometry was used to detect proteolytic peptides and identify host and phage proteins. Generally, phage proteins were detected on a time scale fitting the …


Synthesis, Characterization And Molecular Dynamic Simulations Of Aqueous Choline Chloride Deep Eutectic Solvents, Sampson Asare 2018 South Dakota State University

Synthesis, Characterization And Molecular Dynamic Simulations Of Aqueous Choline Chloride Deep Eutectic Solvents, Sampson Asare

Electronic Theses and Dissertations

Various forms of deep eutectic solvents have been synthesized with advantages of 100% atom economy, low vapor pressure, ease of preparation, cost efficiency, low toxicity, and tunability. Though several DESs have been synthesized and characterized, including binary and ternary solvents, none of the binary DESs have been formulated with water as the sole hydrogen bond donor(HBD). This is due to a couple of opinions. First, water is disruptive to the eutectic bond in tertiary DES. Secondly, the ubiquity and concentration of water even in natural systems have led to the assertion that a solution rather than a eutectic solvent will …


Plasmon-Enhanced Optical Sensing By Engineering Metallic Nanostructures, Peng Zheng 2018 West Virginia University

Plasmon-Enhanced Optical Sensing By Engineering Metallic Nanostructures, Peng Zheng

Graduate Theses, Dissertations, and Problem Reports

The world’s booming population projected to reach 10 billion by 2050 causes enormous stresses on environmental safety, food supply, and healthcare, which in return threatens human civilizations. One of the most promising solutions lies at innovating point-of-care (POC) sensing technologies to conduct detection of environmental hazards, monitoring of food safety, and early diagnosis of diseases in a timely and accurate manner. The discovery of surface-enhanced spectroscopy in the 1970s has significantly stimulated research on light-matter interaction which gives rise to enhanced optical phenomena such as surface-enhanced Raman scattering (SERS), plasmon-enhanced fluorescence (PEF), and particularly, they have found enormous applications in …


Synthesis And Kinetic Activity Analysis Of Substituted Pyrazole, Pyrazoline, And Pyrazolidine Alcohol Dehydrogenase Inhibitors, Meagan E. Hackey 2018 Roger Williams University

Synthesis And Kinetic Activity Analysis Of Substituted Pyrazole, Pyrazoline, And Pyrazolidine Alcohol Dehydrogenase Inhibitors, Meagan E. Hackey

Chemistry Theses

Alcohol dehydrogenase inhibitors may be employed for the treatment of parasitic infection in humans. A series of substituted pyrazoline derivatives were synthesized to elucidate the pharmacophore for the inhibition of ADH. Targeted structure modification was used to alter the electronic and steric interactions associated with the enzyme active site. This study identified several effective N-aryl-carboxamide derivatives with horse liver ADH inhibition, comparable to that of 4-methylpyrazole, a known ADH inhibitor. The identification of pharmacophoric regions will allow for the methodological modification of these compounds to improve enzyme affinity and targeted inhibition. Future research may include additional solubility, toxicity and …


Interfacial Corrosion Of Copper And The Formation Of Copper Hydroxychloride, Mary Teague, Shengxi Li, Hongbo Cong 2018 The University of Akron

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 2018 The University of Akron

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 …


A Consideration Of Ancient Residues And Their Analysis, Jennifer A. Cardinal 2018 University at Albany, State University of New York

A Consideration Of Ancient Residues And Their Analysis, Jennifer A. Cardinal

Legacy Theses & Dissertations (2009 - 2024)

Identification of specific use(s) of ancient pottery vessels through empirical verification is currently very limited for archaeological investigations. Although we can postulate a range of purposes or functions for certain vessels, empirical confirmation of actual use has been determined only for a minuscule portion of the available vessels. This thesis will provide a broad review of organic analyses as applied to foodstuff residues left on ancient artifacts as well as discuss several considerations for such analysis that are unique to their application to archaeological specimens.


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