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Theses/Dissertations

Chemistry

Mass spectrometry

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Full-Text Articles in Physical Sciences and Mathematics

A Top-Down Proteomic Approach For The Discovery Of Novel Serum Biomarkers Of Pregnancy-Related Disease, Karen Merrell Jul 2009

A Top-Down Proteomic Approach For The Discovery Of Novel Serum Biomarkers Of Pregnancy-Related Disease, Karen Merrell

Theses and Dissertations

The serum fraction of blood is an ideal material in which to search for novel biomarkers for disease. It is easily obtained through relatively non-invasive means, routinely collected, and a rich treasure-trove of information about the health of an individual. Cells react to signal molecules, take up nutrients, and release waste products, fragments that are the result of proteolysis, and other molecules out into the bloodstream. If these components are unique to the cells in question, that part of the complex mixture that is the blood stream can potentially characterize the health of the tissue or organ those cells are …

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Detection And Quantification Of Organophosphate Pesticides In Human Serum, Peter Kuklenyik Jul 2009

Detection And Quantification Of Organophosphate Pesticides In Human Serum, Peter Kuklenyik

Chemistry Dissertations

The United States Environmental Agency permits the use of 39 organophosphate pesticides. Many of these pesticides are acutely toxic and have lasting effect on human health. Organophosphates quickly metabolize in the body, therefore currently human exposure is studied by measuring the metabolic products in urine. In this work a suite of analytical methods was developed to determine the presence of un-metabolized organophosphate pesticides in human serum. First mass spectroscopic detection methods were evaluated. Gas chromatograph coupled tandem mass spectrometer was used to compare the detection limits using chemical and electron impact ionization. Positive chemical ionization was selected, because it provided …

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Development Of Quantitative Bioanalytical Methods For The Measurement Of Pharmaceutical Compounds Via Hplc-Uv And Hplc-Ms/Ms, Melissa A. Mcculloch Jan 2009

Development Of Quantitative Bioanalytical Methods For The Measurement Of Pharmaceutical Compounds Via Hplc-Uv And Hplc-Ms/Ms, Melissa A. Mcculloch

ETD Archive

Research in pharmaceutical treatments for illnesses and disease processes has rapidly grown in the past decade. The field is fueled by advances in our understanding of the molecular mechanics of the human body, coupled with the development of sophisticated scientific instruments which can efficiently generate massive amounts of important data. This has led to an ever-growing need for the development of quantitative bioanalytical methods to measure pharmaceutical compounds. In this work, the theory behind the analytical processes and instruments that make these investigations possible is discussed. Further, the development of two high performance liquid chromatographic (HPLC) methods with both ultra …

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Development Of A Novel Gradient Chromatofocusing Tandem Mass Spectometry Technique For The Determination Of Cationic Compounds In Biofluids;Identification Of Caspace 3 Cleavage Sites Of Nhe-1 By High Performance Liquid Chromatography- Mass Spectrometry, Jianhua Tang Jan 2009

Development Of A Novel Gradient Chromatofocusing Tandem Mass Spectometry Technique For The Determination Of Cationic Compounds In Biofluids;Identification Of Caspace 3 Cleavage Sites Of Nhe-1 By High Performance Liquid Chromatography- Mass Spectrometry, Jianhua Tang

ETD Archive

In Part I, work was done to develop a novel gradient chromatofocusing liquid chromatography-tandem mass spectrometry (MS/MS) technique for the determination of ionic compounds in biological matrix. The analysis of ionic compounds poses a great challenge to current LC-MS techniques, due to the fact that there is little or no retention. These ionic compounds are eluted at almost the same time as biological matrix, which is normally directed to waste prior to connecting to the mass spectrometer. A review of current LC-MS techniques for ionic compounds is given in Chapter 1. They all have advantages and disadvantages. To retain and …

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Raman Spectroscopy Of Body Fluids : A Nondestructive Identification Technique For Forensic Applications, Kelly Virkler Jan 2009

Raman Spectroscopy Of Body Fluids : A Nondestructive Identification Technique For Forensic Applications, Kelly Virkler

Legacy Theses & Dissertations (2009 - 2024)

The analysis of body fluid evidence during forensic investigations is a complicated process, yet it is a critical step in determining the key facts of a crime. There is no doubt that DNA analysis is an extremely useful tool that can identify a suspect or victim, but crime scene investigators must first locate and identify potential body fluid stains that can be collected for DNA analysis. Current screening tests are destructive to the sample and can give false positive results, so a nondestructive technique such as Raman spectroscopy, that can possibly confirm the presence of a particular fluid, could lend …

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Merged Electrospray Ionization Mass Spectrometry, Jianan Dong Jan 2009

Merged Electrospray Ionization Mass Spectrometry, Jianan Dong

LSU Doctoral Dissertations

Ambient ionization allows the analysis of materials in their native environment without sample preparation by creating ions outside the mass spectrometer. The goal of this research was to develop new ambient ionization techniques for application to solids, liquids and particles under ambient conditions. Samples to be analyzed were directly merged with an electrospray of droplets, and then ionized and detected by a mass spectrometer. An ion trap mass spectrometer was modified with a nanoelectrospray source and configured for three experiments: merged electrospray ionization of dry particles, merged electrospray ionization of combustion products, and infrared laser desorption/ablation using electrospray for post-ionization. …

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I. Characterization Of Sulfonated Phthalocyanines By Mass Spectrometry. Ii. Characterization Of Siaa, A Streptococcal Heme-Binding Protein Associated With A Heme Abc Transport System, Brian R. Sook Apr 2008

I. Characterization Of Sulfonated Phthalocyanines By Mass Spectrometry. Ii. Characterization Of Siaa, A Streptococcal Heme-Binding Protein Associated With A Heme Abc Transport System, Brian R. Sook

Chemistry Dissertations

Sulfonated phthalocyanines were characterized using capillary electrophoresis and mass spectrometry. Derivatives investigated included the copper, cobalt, zinc and metal-free sulfonated phthalocyanines. The electropherograms of commercially available copper phthalocyanine-3,4',4'',4'''-tetrasulfonic acid and 4,4',4'',4'''-tetrasulfonic acid were very different, consistent with the latter compound having a structure that is not fully sulfonated. Matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) were used to characterize the sulfonated phthalocyanines. Mass spectral evidence was obtained for a pentasulfonated species of both the metal-free phthalocyanine and zinc phthalocyanine when these species were made by sulfonation of the metal-free phthalocyanine (followed by zinc insertion in the latter case). Many …

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Mass Spectrometric Analysis Of Environmental Contaminants, Protein Structure And Expression, Ian E. Atkinson Jan 2008

Mass Spectrometric Analysis Of Environmental Contaminants, Protein Structure And Expression, Ian E. Atkinson

ETD Archive

There are a wide array of sciences at our disposal to further our understanding of the roles of toxins in the environment and their effects on living organisms. Of these disciplines, the field of mass spectrometry offers a powerful analytical means to identify compounds in varying and complex sample media. The presence of altered expressions of biomolecules upon exposure to toxins, the effects that these toxins may have on biomolecule structure and the identity of toxins in the sample all can be determined by mass spectrometry. In this study mass spectrometric analysis has been applied to environmental toxicological problems. First, …

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Mass Spectrometry-Based High Throughput Approach For Identification Of Molecular Modification Of Oxidative Process In Respiratory Diseases, Wei Song Jan 2008

Mass Spectrometry-Based High Throughput Approach For Identification Of Molecular Modification Of Oxidative Process In Respiratory Diseases, Wei Song

ETD Archive

Eosinophil peroxidase (EPO) and myeloperoxidase (MPO) have been implicated in generating reactive species and promoting oxidative modifications in numerous diseases. The detection and identification of potential pathways has been proven extremely challenge due to evanescence nature of these reactive species. An alternative approach to study the involvement of oxidative modification is to detect and quantify the stable molecular fingerprints, like oxidized tyrosine species, in biological matrices. Previously reported analytical methods for quantifying oxidized amino acids have typically been limited by: low sensitivity, specificity and the failure of detection potential oxidation products generated during sample handling. Using GC/MS in combination with …

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Hydration Studies Of Electrospray Ions From Amino Acids And Small Peptides, Chuong Quoc Nguyen Jan 2007

Hydration Studies Of Electrospray Ions From Amino Acids And Small Peptides, Chuong Quoc Nguyen

Theses and Dissertations

This project was undertaken to gain a better understanding of the hydration behaviors of gas phase ions from solutions containing amino acids and peptides. In order to characterize their hydration behavior, the molecules of interest in solutions were first converted into gas phase ions by electrospray ionization (ESI). The completely desolvated ions were then deliberately dispersed into an inert bath gas, usually nitrogen, containing accurately known concentrations of solvent vapor. The resulting mixtures of ions and bath gas were subsequently passed into a vacuum chamber by way of an adiabatic supersonic free jet expansion. The cooling during that expansion caused …

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Characterization Of A Black Coating Overlying Rock Paintings Found In Little Lost River Cave, Idaho Using Thm-Gc-Ms, Jamie Brown-Sinha Jan 2007

Characterization Of A Black Coating Overlying Rock Paintings Found In Little Lost River Cave, Idaho Using Thm-Gc-Ms, Jamie Brown-Sinha

Master's Theses and Doctoral Dissertations

A black coating overlies rock paintings found within Little Lost Rive Cave, Idaho. A calibrated radiocarbon date of 1390-1040 B.C. was obtained by Steelman et al.1 However, this relies on the assumption that the black coating was formed by some human activity. For further characterization and to verify that the coating is anthropogenic, THM-GC-MS was performed on various samples collected throughout the cave, including soil samples from inside, outside, and above the cave. Humic and fulvic acids, synthetic and natural melanin, and experimentally created cooking residues were also analyzed as standard materials. By comparing the resulting chromatograms and the compounds …

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Chemical Differences Of Atherosclerotic Plaques In Native And Bypass Human Coronary Arteries And Diseased And Non-Diseased Human Aortas, Samuel Jean Washington Jan 2007

Chemical Differences Of Atherosclerotic Plaques In Native And Bypass Human Coronary Arteries And Diseased And Non-Diseased Human Aortas, Samuel Jean Washington

LSU Doctoral Dissertations

ABSTRACT Cardiovascular disease, primarily atherosclerosis involves a number of distinct processes that are associated with plaque development. The use of differential gel electrophoresis to determine differences between proteins produced in native and bypass coronary arteries from the same heart has been studied. The analytical techniques presented in this study to characterize plaque samples include two dimensional gel electrophoresis, sodium dodecylsulfate polyacrylamide gel electrophoresis, mass spectrometry, differential gel electrophoresis, and high performance liquid chromatography. An overview of the stages involved in atherosclerosis and the theories implicated in the manifestation of atherosclerosis was presented. A design study using the Box Behnken method …

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Development Of Methods For The Study Of Phosphoproteins, Zhaoyuan Chen Dec 2006

Development Of Methods For The Study Of Phosphoproteins, Zhaoyuan Chen

Theses and Dissertations

Characterization of phosphoproteins-including detection, identification of phosphoproteins and identification of phosphorylation sites-is mostly done with radiolabeling and proteomic techniques. Three main topics related to phosphoprotein characterization are included in this dissertation. First, large-scale characterization of the CHO (Chinese hamster ovary) cell phosphoproteome was done using two dimensional gel electrophoresis (2DE) separation, visualization of phosphoproteins by radiolabeling or a phosphoprotein specific dye, followed by MALDI-TOF identification. Because radiolabeling of phosphoproteins is very sensitive and straightforward to quantify, such analysis can give a clear picture of the relative phosphosphorylation of proteins present in a sample. But there are also limitations to this …

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Biochemical Investigations Of Macular Degeneration: The Significance Of Protein Oxidation Including Novel Methods For Its Study, Sarah Warburton Nov 2006

Biochemical Investigations Of Macular Degeneration: The Significance Of Protein Oxidation Including Novel Methods For Its Study, Sarah Warburton

Theses and Dissertations

The retinal pigment epithelium (RPE) is a monolayer of cells located directly behind the photoreceptor cells in the retina. These cells are involved in a variety of functions that support the visual process in the eye, namely 1) they form a blood-retina barrier which separates the neural retina from the choroid's blood supply, 2) the apical processes of RPE cells diurnally phagocytose the outer segments of photoreceptor cells, and 3) they participate in the renewal of the photopigment 11-cis retinal. Age-related macular degneration (AMD) is the leading cause of blindness in people over the age of 50 years in North …

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Enhanced Electrospray Ionization For Mass Spectrometry And Ion Mobility Spectrometry, Li Zhou Jul 2006

Enhanced Electrospray Ionization For Mass Spectrometry And Ion Mobility Spectrometry, Li Zhou

Theses and Dissertations

Electrospray ionization (ESI) has become one of the most commonly used ionization techniques for mass spectrometry (MS) and ion mobility spectrometry (IMS), and efforts continue to improve its performance. ESI-MS is most recognized for its wide application to biomacromolecules where high sensitivity is of paramount importance. However, the major limitation in sensitivity with ESI-MS is due to its low ion transmission efficiency from the ESI source into the sampling orifice and through any stages utilized for transfer of ions from atmosphere to vacuum in the MS. A series of atmospheric pressure ion focusing interfaces were designed and implemented to enhance …

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Integrating Micro-Scale Separations To Matrix Assisted Laser Desorption And Ioniation Time Of Flight Mass Spectrometry (Maldi-Tof-Ms) For Protein Analysis, Harrison K. Musyimi Jan 2006

Integrating Micro-Scale Separations To Matrix Assisted Laser Desorption And Ioniation Time Of Flight Mass Spectrometry (Maldi-Tof-Ms) For Protein Analysis, Harrison K. Musyimi

LSU Doctoral Dissertations

This dissertation describes the integration of micro-scale separations to matrix assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI TOF MS) for protein analysis. MALDI MS provides unsurpassed accurate mass measurements of intact bio-molecules, for example peptides and proteins, which in turn generate high molecular specificity enabling the identity, function and structure of these molecules to be characterized. However, in order to realize the full potential of MS in proteomic studies, integrated sample processing on automated and high throughput platforms is required to address the complexity, diversity and the dynamic range of proteomic analysis. The work described here contributes towards …

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Infrared Laser Desorption/Ionization Mass Spectrometry: Fundamental And Applications, Mark Little Jan 2006

Infrared Laser Desorption/Ionization Mass Spectrometry: Fundamental And Applications, Mark Little

LSU Doctoral Dissertations

This dissertation on infrared laser desorption/ionization mass spectrometry encompasses fundamental studies of the desorption/ionization process and direct-from-gel laser desorption/ionization applications. Understanding of the fundamentals behind desorption and ionization can lead to improvements in the technique and to new applications. Experiments aimed at advancing this goal are wavelength studies and two-laser infrared/ultraviolet matrix-assisted laser desorption/ionization experiments. The direct-from-gel laser desorption/ionization application in which infrared laser desorption/ionization of analytes directly ionized after gel electrophoretic separation will also be presented. Protein and peptide standards were used as test analytes and the infrared lasers used were a 10.6 micrometers carbon-dioxide laser and a mid-IR …

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Characterization Of Black Deposit Associated With Rock Paintings In Little Lost River Cave, Idaho Using Pyrolysis Gc, Sarah Therese Fezzey Jan 2005

Characterization Of Black Deposit Associated With Rock Paintings In Little Lost River Cave, Idaho Using Pyrolysis Gc, Sarah Therese Fezzey

Master's Theses and Doctoral Dissertations

A black, shiny coating overlies rock paintings in Little Lost River Cave no. 1, located in southeastern Idaho. If this coating is the result of human activity within the cave – a condensate from cooking fires, for example – then a radiocarbon date on the coating would provide a minimum age for the underlying paintings. The work reported here was undertaken to test the assumption that the coating has an anthropomorphic origin. Using pyrolysis-gas chromatography-mass spectrometry (py-GC-MS) and thermally-assisted hydrolysis/methylation-GC-MS, we have compared samples of the black coating from Idaho to humic acid, a geologic material; an experimental cooking residue; …

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The Synthesis Of Deuterated Arylamine Dna Adducts For Use In The Development Of An Isotope Dilution Lc/Ms/Ms Method, Philip Dmitri Olsen Jan 2001

The Synthesis Of Deuterated Arylamine Dna Adducts For Use In The Development Of An Isotope Dilution Lc/Ms/Ms Method, Philip Dmitri Olsen

LSU Doctoral Dissertations

Polycyclic aromatic amines (arylamines) are a class of chemical carcinogens that are prevalent in environmental and industrial settings. In order to study the mechanism of their toxicity a quantitative and qualitative detection method was developed to measure the C8-adenine adducts of benzidine and 2-aminofluorene in DNA samples. To do this a novel synthetic method using a palladium catalyst was developed to prepare authentic and deuterated arylamine adducts to serve as standards. These standards were then used to develop a high performance liquid chromatography, electrospray, tandem mass spectrometry, isotope dilution, detection method. To demonstrate the validity of this method two spike …

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Low Pressure Gas Flow Analysis Through An Effusive Inlet Using Mass Spectrometry, David Robert Brown Apr 1988

Low Pressure Gas Flow Analysis Through An Effusive Inlet Using Mass Spectrometry, David Robert Brown

Chemistry & Biochemistry Theses & Dissertations

A mass spectrometric method for analyzing flow past and through an effusive inlet designed for use on the tethered satellite and other entering vehicles is discussed. Source stream concentrations of species in a gaseous mixture are determined using a calibration of measured mass spectral intensities versus source stream pressure for standard gas mixtures and pure gases. Concentrations are shown to be accurate within experimental error. Theoretical explanations for observed mass discrimination effects as they relate to the various flow situations in the effusive inlet and the experimental apparatus are discussed.

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