Chemistry Commons^™

Optimization Of Gradient Chromatofocusing For The Protein Separation And Lc-Ms/Ms Determination Of Ngp1-01 In Mouse Serum, Brain, And Retina, Harini Jogiraju

ETD Archive

No abstract provided.

Gradient Chromatofocusing And Reversed Phase Hplc In Protein Analysis And Lc-Ms/Ms Determination Of Thiazolidinedione Nl-1 In Mouse Serum And Brain, Kiran K. Pedada

ETD Archive

No abstract provided.

Laser Ablation Sample Transfer For Mass Spectrometry, Sung-Gun Park

LSU Doctoral Dissertations

In this research, a new ambient sampling technique for mass spectrometry was developed that uses an infrared laser to ablate materials under ambient conditions that are captured in a solvent or on a surface. An infrared optical parametric oscillator (OPO) laser system at 3 μm wavelength was focused onto samples for ablation at atmospheric pressure. The ablated materials were transferred to a solvent or surface. For off-line electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) analysis, the ablated material was captured in a static solvent droplet that was deposited on a MALDI target or flow-injected into a nanoelectrospray source. The …

From Whole-Cell To Compartment- And Class-Specific Analysis Of Rna Post-Transcriptional Modifications, Ryan Quinn

Legacy Theses & Dissertations (2009 - 2024)

The genomic structure of the human immunodeficiency virus type 1 (HIV-1) has proven difficult to examine by traditional high-resolution techniques. Structural probing and in silico modeling have been turned to the task instead. Computer models are only as robust as the data used to create them. A number of techniques were explored in this investigation to expand the utility of in silico modeling as it relates to HIV-1: the study of nucleoside modifications, and the probing of in vivo conformations of the 5'-untranslated region (5'-UTR) by cross-linking and affinity capture.

Mass Spectrometric Analysis Of Oxidized Eicosapentaenoic Acid Sodium Salt, Kelsey D. Jordan, Rita K. Upmacis

Faculty Papers and Publications

Eicosapentaenoic acid (EPA) is an omega-3 polyunsaturated fatty acid (PUFA) with 20 carbon atoms and 5 carbon-carbon double bonds. Mammalian cells cannot synthesize long chain PUFAs such as EPA de novo, and, thus, the most effective way to enrich cells in EPA is by dietary intake of fish oils. EPA supplementation causes an increase in its concentration in plasma lipids and in cell membrane phospholipids. Many beneficial effects of EPA supplementation have been noted, including (1) the potential to sensitize cancerous tumors towards chemotherapy, (2) the promotion of cardiovascular health, and (3) the alleviation of some mental disorders, but results …

Detection Of Microorganisms Using Maldi And Ion Mobility Mass Spectrometry, Juaneka Monet Hayes

LSU Doctoral Dissertations

Matrix-assisted laser ablation desorption ionization MALDI and ion mobility (IM) MALDI mass spectrometry (MS) were used for the detection and identification of microorganisms. MALDI MS is an analytical tool that separates ions by their mass-to-charge ratio (m/z) and is routinely used for bioanalysis because of its sensitivity, selectivity, general applicability, and tolerance to impurities. Ion mobility is a gas phase technique that separates ions based on their charge and collision cross-section. In this research, MALDI-TOF MS and MALDI-IM-TOF MS analysis were conducted in parallel to assess the effectiveness of MALDI-IM-TOF MS for microorganism identification. Whole cell bacteria Escherichia coli strain …

Direct Analysis Of Hops By Leaf Spray And Paper Spray Mass Spectrometry, Kari Blain

Masters Theses

The objective of this research is to develop a new and innovative method of hops analysis, which is much faster than standard testing methods, as well as reduce the amount of consumables and solvent used. A detailed discussion on the development of an ambient ionization mass spectrometry method called paper spray (PS-MS) and leaf spray (LS-MS) mass spectrometry will be presented. This research investigates the use of PS-MS and LS-MS techniques to determine the α- and β- acids present in hops. PS-MS and LS-MS provide a fast way to analyze hops samples by delivering data as rapidly as a UV-Vis …

New Applications Of Mass Spectrometry For Drug And Lipid Analysis, Elizabeth Lauren Emerson

Graduate Theses and Dissertations

Mass spectrometry is an important tool used in many different disciplines and settings that include forensics, drug discovery, environmental analysis, and proteomics. Gas chromatography - mass spectrometry (GC-MS) and matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI - TOF MS) are two of the most important instruments used for analysis of compounds. Chapters 1 and 2 of this discussion use GC-MS for the investigation of synthetic cannabinoids in `K2' incense products and the detection of metabolites in urine samples from individuals suspected of consuming these mixtures. Analytical standards were synthesized and used for identification and confirmation of structures. Detection of …

Capturing Fleeting Intermediates In A Catalytic C-H Amination Reaction Cycle, Richard H. Perry, Thomas J. Cahill Iii, Jennifer L. Roizen, Justin Du Bois, Richard N. Zare

Chemistry and Physics Faculty Articles

We have applied an ambient ionization technique, desorption electrospray ionization MS, to identify transient reactive species of an archetypal C–H amination reaction catalyzed by a dirhodium tetracarboxylate complex. Using this analytical method, we have detected previously proposed short-lived reaction intermediates, including two nitrenoid complexes that differ in oxidation state. Our findings suggest that an Rh-nitrene oxidant can react with hydrocarbon substrates through a hydrogen atom abstraction pathway and raise the intriguing possibility that two catalytic C–H amination pathways may be operative in a typical bulk solution reaction. As highlighted by these results, desorption electrospray ionization MS should have broad applicability …

Preparation Of Novel Endohedral Metallofullerenes By The Krätschmer-Hoffman Arc Reactor Method, Markus J. Meyer, Manuel N. Chaur, Luis A. Echegoyen

COURI Symposium Abstracts, Summer 2012

Since the discovery of C₆₀ fullerene 25 years ago, the pursuit of encapsulating different metals, metallic clusters, and small molecules have attracted the attention of the scientific community due to the possibility of tuning the electronic and chemical properties of these compounds. As of today various metal-non-metal combinations have been obtained such as metallic nitrides, sulfides, metal carbides and metal oxides, however, none of them (except for Sc₃N@C₈₀) has been prepared in high yields. In this work we study the preparation process of different metallofullerenes and the dependence of the fullerene yield on various parameters …

Identification And Quantification Of Protein Carbonylation By Mass Spectrometry, Qingyuan Liu

Theses and Dissertations

Accumulated evidence indicates oxidative stress plays important roles in disease and aging. Under oxidative stress, lipid peroxidation (LPO) leads to reactive carbonyl species (RCS) that can modify a wide range of biomolecules including protein, DNA and carbohydrate. In this dissertation, we investigate the modification of two model proteins, human serum albumin (HSA) and aconitase (ACO), by the LPO-relevant a, b-unsaturated aldehydes, acrolein (ACR) and 4-hydroxy-2-nonenal (HNE). The investigation is focused on the characterization and quantification ACR and HNE addition to the model proteins. A correlation between HNE modification and ACO activity is also determined. These results provide insights into the …

Monitoring The Health Of Glen Helen Nature Preserve: Spring 2012 Sediment And Water, Audrey E. Mcgowin Ph.D., Triet Minh Truong, David Kammler Ph.D., Joe Solch

Chemistry Student Publications

This poster presents the results for environmental testing in Glen Helen by the Special Topics in Analytical Chemistry course at Wright State University under the direction of Professor Audrey McGowin in Spring 2012. Water quality data are presented for the Yellow Spring in Yellow Springs, Ohio for April and May of 2012. Other test sites range from locations along Yellow Springs Creek to the covered bridge near Little Miami River.

This poster was created by Triet M. Truong.

Chronic Kidney Disease: Vitamin D Treatment Regimens And Novel Assay Development For Kidney And Cardiovascular Function Biomarkers, Joe M. El-Khoury

ETD Archive

Chronic kidney disease (CKD) is highly prevalent in the US population and has high incidence of cardiovascular and all-cause mortality. A known complication of CKD is secondary hyperparathyroidism that is caused by bone and mineral imbalances, including vitamin D deficiency. Supplementation of CKD patients with vitamin D is based on guidelines issued by the Kidney Disease Quality Outcomes Initiative (K/DOQI), which recommend administration of vitamin D2 in variable doses depending on the severity of vitamin D deficiency. Retrospective and pilot studies have shown that vitamin D2 was not as effective as vitamin D3 in treating vitamin D deficiency. In Chapter …

Ambient Ionization Mass Spectrometry Analysis Pertaining To Biofuel Process Development, Sushma Dendukuri

Online Theses and Dissertations

Mass spectrometry (MS) has undergone a revolution with the introduction of a new group of desorption/ionization (DI) techniques known collectively as Ambient Ionization mass spectrometry. Ambient ionization mass spectrometry allows for direct analysis of analytes and typically requires little or no sample preparation. Specifically, Direct Analysis in Real Time (DART) has developed rapidly and allowed investigations to occur with the analysis of biomass after various pretreatments to determine the pretreatment biomass degradation efficiency. The degradation of the initial biomass structure is a very important step before other chemical treatments can occur to generate needed sugars. Since generated sugars aid in …

Computational Methods For The Differential Profiling Of Triacylglycerols Using Rp-Hplc/Apci-Ms, Margaret Holbrook Broadwater

MUSC Theses and Dissertations

Reversed phase liquid chromatography with atmospheric pressure chemical ionization mass spectrometry (RP-HPLC/APCI-MS) was employed for the analysis of natural mixtures of triacylglycerols. An integrated framework for data analysis, including preprocessing, statistical analysis and automated structure identification, was implemented in the R statistical program. Raw data stored as mzXML, mzData, or mzXML files are preprocessed using a series of steps for peak detection, chromatographic alignment, and normalization. Targeted and non-targeted feature selection steps are employed to filter the data for features that are relevant and informative for a particular biological question. Triacylglycerol structures are identified by evaluating relationships between the diacylglycerol …

Tandem Mass Spectrometric Analysis Of Ammonium And Sodium Oligoperoxide Adducts With The Application Of Two-Dimensional Correlation Spectroscopy And Computational Chemistry, Jessica Lynne Frisch

Electronic Theses and Dissertations

Oligoperoxides, H[OO(CH3)2C]nOOH, are formed as side products in the synthesis of the primary high explosive triacetone triperoxide (TATP). Previous tandem mass spectrometry (MSn ) experiments using a quadrupole ion trap reported that the openchained oligoperoxide adducts of ammonium or sodium resulted in different product ions in the mass spectra. Dissociation mechanisms were previously proposed based on MSn experiments, where n > 2; however, a dissociation pathway achieved by an MSn experiment, where n > 2, may not necessarily be the same pathway achieved in an MS2 experiment. For this dissertation research, the collision induced dissociation pathways were investigated for the open-chained oligoperoxides …

Infrared Laser Ablation For Biological Mass Spectrometry, Fan Huang

LSU Doctoral Dissertations

Instrument and technique development and modeling of ionization methods using infrared (IR) laser desorption and ablation for mass spectrometry (MS) analysis of chemical and biochemical samples are described. Infrared lasers are highly efficient at sample removal and post-ablation ionization of materials removed by IR laser can be used to improve ionization efficiency. Fundamental studies of the physical processes in laser ablation mass spectrometry can help elucidate the mechanism. In this research, an infrared/ultraviolet two-laser matrix-assisted laser desorption ionization (MALDI) MS was developed for analysis of biomolecules. An infrared laser was used to ablate a mixture of analyte and matrix, and …

Development Of A Novel Electron-Transfer Secondary Reaction Matrix, Characterization Of The Site–Specificity Of Novel Bilin-Lyase, And Fundulus Grandis Protein Expression Investigation Using Mass Spectrometry, Mohamed N. Boutaghou

LSU New Orleans Theses and Dissertations

Reported in this dissertation are the results of investigations performed at the New Orleans Center for Mass Spectrometry at the University of New Orleans. The projects that are detailed in the coming pages take on a variety of subjects, but a common thread is that each employs matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to solve a problem. Fundamental aspects of MALDI in-plume ionization are implicated in the introduction of a newly developed electron-transfer secondary ionization matrix. The remaining projects are related to the ever expanding field of proteomics. Mass spectrometry was used to investigate the site specificity of a newly …

Novel Ion Trap Made Using Lithographically Patterned Plates, Ying Peng

Theses and Dissertations

A new approach of making ion trap mass analyzers was developed in which trapping fields are created in the space between two ceramic plates. Based on microfabrication technology, a series of independently-adjustable electrode rings is lithographically patterned on the facing surfaces of each ceramic plate. The trapping field can be modified or fine-tuned simply by changing the RF amplitude applied to each electrode ring. By adjusting the potential function applied to the plates, arbitrary trapping fields can be created using the same set of ceramic plates. Unlike conventional ion traps, the electrodes of planar ion traps have a non-equipotential surface, …

Instrumentation Analysis For Large Molecules: A Theoretical Study And Simulations, Yi She

Student Theses and Dissertations

Instrumentation analysis such as mass spectrometry allows one to analyze size up to 100kD safely. Difficulty arises from kinetic energies carried by larger-size molecules. Currently our group is developing a high pressure device, and the plan requires a theory (mathematics and physics) to back it up and highly accurate simulations for visualization and interpretation of the theoretical results. Such simulation is computationally (time-wise) difficult because of immense number of collisions. In our first trial of larger-molecule simulation, we incorporate a concept of drag with slip correction factor, relaxation time, and fluid viscosity into a statistical trajectory model currently common used. …

Quantitative And Qualitative Mass Spectrometric Analysis Of Anticancer Agents, Drugs Of Abuse And Enzyme-Inhibitor Complexes, Keri M. Smith

ETD Archive

Mass spectrometry is a valuable tool in the analysis of many types of compounds. From small molecules to large proteins, mass spectrometry can help to interrogate samples and give insights to the origins of disease as well as calculate an exact concentration. Bioanalytical method development is an integral component in the measurement of such compounds. To facilitate proper analytical investigation, the process of method development, analysis, and interpretation must be understood. This work describes the basis and procedure for bioanalytical method development and its detailed application to preclinical studies of the antineoplastic agent hexamethylene bisacetamide and measurement ofillicit drugs of …

Development Of Bioanalytical Methods For Clinical Applications And Drug Screening, Xiaohan Cai

ETD Archive

In the past decade, bioanalytical method development has become an integral part of clinical diagnosis, biomarker discovery, and drug discovery and development. The new and emerged bioanalytical technologies allow the quantitative and qualitative analysis of small molecules and biomolecules with high sensitivity and specificity. Specifically, the bioanalytical methods based on LC-MS and methylation-specific PCR are well suited for detecting low-abundance metabolites, proteins, and DNA in biofluids and tissues for biomarker investigation. They offer great clinical promises for early diseases diagnosis and therapeutic interventions. Besides, the LC-MS/MS quantitative method is essential for the estimation of pharmacokinetic and toxicological properties in drug …

Capillary Gradient Chromatofocusing-Mass Spectrometry;A Sensitive Approach For Protein Analysis, James Anthony Hribar

ETD Archive

Gradient chromatofocusing-mass spectrometry is a new technique for protein analysis recently introduced by our research group. Capable of separating and identifying proteins according to pI values and molecular weight, gradient chromatofocusing-mass spectrometry has been achieved by integrating a new ion-exchange chromatography technique called gradient chromatofocusing with a newly discovered buffer system that promotes mass spectrometry detection. Differing from traditional ion-exchange chromatography techniques, gradient chromatofocusing employs specific low molecular weight, volatile buffer components that are introduced onto an ion-exchange HPLC column by programming a binary gradient pumping system to deliver the correct proportions of acidic mobile phase to overcome buffering of …

Development Of Quantitative Lc-Ms/Ms Methods For The Pharmacological Studies Of Anti-Cancer Drugs, Lan Li

ETD Archive

In the development of anti-cancer drugs, it is essential to study the pharmacological profiles of the drugs. Among the analytical tools utilized in the pharmacological studies, LC-MS/MS has gained increased popularity due to its unequivocal sensitivity and specificity, as well as the ability of handling a wide variety of compounds with relatively simple sample preparation procedures. In this work, a brief review on the method rational, instrumentations, analytical method validation, and work flow of the method development was included. The processes of LC-MS/MS method development for the pharmacological studies of three anti-cancer drugs (i.e., methoxyamine, fludarabine, and 6-benzylthioinosine) were illustrated. …

Proteomic Analysis Of The Blood Of Alligator Mississippiensis, Lancia Nadinia Fallen Darville-Bowleg

LSU Doctoral Dissertations

My research focus was to investigate alligator blood using mass spectrometry-based proteomics methods to understand their innate immune systems. The first goal was to sequence peptides and proteins from the blood serum and leukocytes using tandem mass spectrometry and de novo sequencing. The second goal was to determine the function of these biological molecules and their relationship to the immune system. One- and two-dimensional gel electrophoresis was used to separate proteins from alligator leukocytes, which were enzymatically digested. The peptides were measured using reversed phase nano-high performance liquid chromatography coupled with tandem mass spectrometry (nano-HPLC-MS/MS) followed with de novo sequencing. …

Halo Ion Trap Mass Spectrometry: Design, Instrumentation, And Performance, Miao Wang

Theses and Dissertations

New ion trap mass spectrometry (ITMS) instrumentation, the toroidal IT and halo IT, were developed to meet the significant growth in on-site analysis applications. The miniature toroidal IT mass analyzer was operated with radio frequency (RF) trapping voltages of 3 kVp-p or less. Despite its reduced dimensions, it has roughly the same ion trapping capacity as conventional 3D quadrupole ITs. Unit-mass resolved spectra for n-butylbenzene, xenon, and naphthalene were obtained. The desired linear mass scale was obtained using conventional mass-selective instability scan combined with resonance ejection. The halo IT was also based on toroidal trapping geometry and microfabrication technology, consisting …

Characterization Of Glycation Sites On Human Serum Albumin Using Mass Spectrometry, Omar S. Barnaby

Department of Chemistry: Dissertations, Theses, and Student Research

The modification of proteins by reducing sugars is a process that occurs naturally in the body. This process, which is known as glycation, has been linked to many of the chronic complications encountered during diabetes. Glycation has also been linked to changes in the binding of human serum albumin (HSA) to several drugs and small solutes in the body. While these effects are known, there is little information that  explains why these changes in binding occur. The goal of this project was to obtain qualitative and quantitative information about glycation that occurs on HSA. The first section of this dissertation …

Statistical Analysis Of Visible Absorption Spectra And Mass Spectra Obtained From Dyed Textile Fibers, Katie Margaret White

Electronic Theses and Dissertations

The National Academy of Sciences recently published a report which calls for improvements to the field of forensic science. Their report criticized many forensic disciplines for failure to establish rigorously-tested methods of comparison, and encouraged more research in these areas to establish limitations and assess error rates. This study applies chemometric and statistical methods to current and developing analytical techniques in fiber analysis. In addition to analysis of commercially available dyed textile fibers, two pairs of dyes are selected based for custom fabric dyeing on the similarities of their absorbance spectra and dye molecular structures. Visible absorption spectra for all …

Microfluidic Devices Interfaced To Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry For Proteomics, Jeonghoon Lee

LSU Doctoral Dissertations

Microfluidic interfaces were developed for off-line matrix-assisted laser desorption/ionization mass spectrometry (MALDI). Microfluidic interfaces allow samples to be manipulated on-chip and deposited onto a MALDI target plate for analysis. For this research, microfluidic culturing devices and automated digestion and deposition microfluidic chip platforms were developed for the identification of proteins. The microfluidic chip components were fabricated on a poly(methyl methacrylate), PMMA, wafer using the hot embossing method and a molding tool with structures prepared via micromilling. One of the most important components of the chip system was a trypsin microreactor. An open channel microreactor was constructed in a 100 µm …

Corrosion Behavior Of Copper Thin Films In Organic Hf-Containing Cleaning Solution For Semiconductor Applications, Nabil George Mistkawi, Makarem A. Hussein, Malgorzata Ziomek-Moroz, Shankar B. Rananavare

Chemistry Faculty Publications and Presentations

The corrosion behavior of electrochemically deposited copper thin films in deaerated and non-deaerated commercial cleaning solutions containing HF was investigated. Potentiodynamic polarization experiments were carried out to determine active, active–passive, passive, and transpassive regions. Corrosion rates were calculated from Tafel slopes. The addition of hydrogen peroxide to the solution and its influence on corrosion was also investigated by employing inductively coupled plasma-mass spectroscopy (ICP-MS) and X-ray photoelectron spectroscopy (XPS). The ICP-MS and potentiodynamic methods yielded comparable Cu dissolution rates. Surface analysis using atomic force microscopy and scanning electron microscopy, performed before and after the cleaning solution treatment, did not reveal …