Physical Sciences and Mathematics Commons^™

Characterization Of Small Molecules And Ions By Atmospheric Pressure Ionization-Mass Spectrometry, Maleesha De Silva

Theses and Dissertations

Mass spectrometry (MS) has become a widely used technique for the characterization of a wide range of substances in diverse fields. The selection of appropriate ionization techniques, source parameters, charge carriers based on the analyte’s polarity is essential in MS as only the ions are detected. When using a soft ionization technique, single stage-MS at best provides only chemical composition; thus, tandem MS is needed to determine structural information and dissociation pathways. This dissertation focuses on the characterization of various small molecules and ions using different ionization techniques, charge carriers, and collision-induced dissociation (CID).

In Chapter II, commercially available ionic …

Mass Spectrometry Directed Pre-Clinical Studies Of Asthma Candidate Midd0301 And Its Analogs, Md Shadiqur Rashid Roni

Theses and Dissertations

ABSTRACTMASS SPECTROMETRY DIRECTED PRE-CLINICAL STUDIES OF ASTHMA CANDIDATE MIDD0301 AND ITS ANALOGS by Md Shadiqur Rashid Roni The University of Wisconsin-Milwaukee, 2021 Under the Supervision of Professor Alexander (Leggy) Arnold

Asthma is one of the most prevalent global health problems. More than 25 million Americans are suffering from asthma and their symptoms especially in children are not well controlled with current medications. The current therapeutic options to control symptoms are limited and are commonly based on inhaled corticosteroids. There are several reasons for uncontrolled asthma symptoms that includes steroid resistance, improper use of inhalers and very few orally available medications. …

Mechanisms And Applications Of Improved Protein Analysis By Desorption Electrospray Ionization Mass Spectrometry (Desi-Ms), Roshan Javanshad

Dissertations

Electrospray ionization mass spectrometry (ESI-MS) is a soft ionization technique that allows detection of macromolecules, such as intact proteins, by the formation of multiply charged ions from solutions. Desorption electrospray ionization mass spectrometry (DESI-MS) is an ambient ionization technique that directly samples analyte from a surface during ESI-MS analysis. Although DESI-MS is highly accomplished at the analyses of metabolites, lipids, and other small molecules, it is far more limited when it comes to protein analysis. While most of the field in ambient ionization MS has moved towards primarily applications, our approach has been to explore the use of DESI-MS and …

Characterization Of Biological Samples Using Multi-Modal Mass Spectrometry, Yarixa L. Cintron-Diaz

FIU Electronic Theses and Dissertations

There is a need for fast, accurate and cost-effective protocols capable of assessing biomolecules at the molecular level (e.g., proteins, lipids and metabolites) from biological specimens. Mass spectrometry (MS) based techniques have become the analytical gold standard for identification and characterization of biomarkers in biological samples. The high throughput and short analysis time scales enables to follow biological processes while providing detailed chemical and spatial characterization. One of the current challenges in biological MS, is the high molecular complexity, chemical diversity and dynamic range. In this dissertation, the use of multi-modal mass spectrometry workflows -mass spectrometry imaging and ion mobility …

Non-Target Analysis Using High-Resolution Mass Spectrometry To Characterize And Remediate Urban Waters, Brian Ng

FIU Electronic Theses and Dissertations

The first part of this dissertation will focus on the development of a simple, robust online solid phase extraction liquid chromatography high resolution mass spectrometry (SPE LC-HRMS) method followed by the use of computational software workflows for non-target analysis (NTA) of environmental samples (development). The benchmarks to assess reproducibility are not well defined for non-target analysis. Parameters to evaluate analytical performance, such as accuracy, precision and selectivity, are well defined for target analysis, but remain elusive for non-target screening analysis. In this study, quality control (QC) guidelines are proposed to assure reliable data in NTA methodologies using a simple …

Investigating The Chemistry Of Harmful Algal Blooms And Microbial Communities In The Natural Environment, Samuel Patrick Putnam

Theses and Dissertations

Cyanobacteria has existed on the planet for over 3 billion years, and as technology, science, and industry have allowed us to shape our world, these changes have caused a proliferation of biomass. Higher carbon dioxide levels in the atmosphere, warmer temperatures, and rapid increases in the nutrient cycle have created excellent growing conditions for cyanobacteria, making them endemic in fresh waters throughout the world. The work in this dissertation was directed towards the secondary metabolites produced by cyanobacteria and other surrounding microbes and understanding their concentrations and release in natural systems. Analytical methods were developed for the extraction and quantification …

Don't Sell Them Short, There's More To Bacterial Natural Products Than Antibiotics, Alison Clare Domzalski

Dissertations, Theses, and Capstone Projects

Recent genomic studies of microbiomes have revealed an overwhelming number of biosynthetic genes of unknown function. Most of these “cryptic” biosynthetic genes are not expressed in laboratory monocultures of individual microbes. Thus, there remains tremendous untapped potential for natural products discovery. Here we employ mixed microbial culture (MMC) as a simple yet powerful approach to awaken cryptic biosynthetic gene clusters. Our preliminary studies demonstrated that arrays of metabolites could be induced in MMCs upon environmental cues, such as surface adhesion. Using this system, we have screened, identified, and isolated bioactive bacterial metabolites, which were characterized structurally and biologically. Of the …

Mass Spectrometry Based Metabolomics And Lipidomics., Fang Yuan

Electronic Theses and Dissertations

Metabolomics and lipidomics studies are important to understand living organisms at the molecular level. In this dissertation, I conducted various untargeted and targeted metabolomics and lipidomics studies using mass spectrometry based analytical platforms. Firstly, I investigated the androgen depletion effects on fecal metabolites in a mouse model of systemic lupus erythematosus and metabolite biomarkers for colorectal cancer using two-dimensional gas and liquid chromatography-mass spectrometry. Secondly, I investigated the relationship between gut microbiota-mediated resistance and susceptibility to malaria and the production of short-chain fatty acids using gas chromatography-mass spectrometry. Thirdly, I developed a high-throughput liquid chromatography-mass spectrometry method to profile long-chain …

Records Of Enriched Uranium Atmospheric Deposition In Pond Sediments In Piketon, Oh, Brianna Herner, Brian Majestic, Michael Ketterer

DU Undergraduate Research Journal Archive

The enrichment of uranium, often for nuclear weapons programs and commercial nuclear reactors, produces higher concentrations of radioactive uranium 235 (²³⁵U) than what naturally occurs, which can pose a human health hazard. The most abundant naturally occurring uranium isotope is ²³⁸U, which is still radioactive, however a higher concentration of ²³⁵U skews the observed isotopic uranium distribution. The Department of Energy Portsmouth Gaseous Diffusion Plant, located near Piketon, OH, enriched uranium from 1954 to 2001 and ²³⁵U pollution has recently been detected in air and sediment samples in the surrounding community. The extent of the …

Integrated Mass Spectrometry-Based Method In Protein Chemistry: Metal-Binding Protein And Integral Membrane Protein, Chunyang Guo

Arts & Sciences Electronic Theses and Dissertations

Most biological processes are associated with protein catalysis. Characterizing protein structure, therefore, is crucial for understanding biological function. Mass spectrometry (MS)-based methods have emerged as a pivotal biophysical tool to interrogate protein structures; they can characterize protein-ligand/protein complexes that are refractory to conventional high-resolution means such as X-ray crystallography, Cryo-EM, and nuclear magnetic resonance (NMR) spectroscopy, in part owing to high molecular weight and significant flexibility. The integrated MS-based platform will provide topology and structural information of proteins from sketch to detail; native MS identifies protein complexes’ composition and stoichiometry; hydrogen-deuterium exchange MS (HDX-MS) detects the protein complexes’ dynamic change …

Mass Spectrometry-Based Strategies In Protein Higher Order Structure Analysis: Fundamentals And Applications In Protein-Ligand Interactions, Xiaoran Liu

Arts & Sciences Electronic Theses and Dissertations

Protein ligand interaction is a fundamental question in biology and biochemistry, and many approaches including X-ray crystallography, nuclear magnetic resonance, cryogenic electron microscopy, mass spectroscopy (MS), infrared spectroscopy, circular dichroism, fluorescence spectroscopy and many others have been applied to address this question. Among these techniques, mass spectroscopy has the advantage of high throughput, low sample amount requirement, and mid-to-high spatial resolution. One of the MS-based approaches is protein footprinting, which utilizes labeling reagents to map the solvent accessible surface of the protein of interest thus deliver structural information. Irreversible labeling is represented by covalent labeling and radical labeling, in which …

Validation Of A Deployable Proteomic Assay For The Serological Screening Of Sexual Assault Samples, Catherine O'Sullivan Brown

Electronic Theses and Dissertations

Protein mass spectrometry (MS) has emerged as a technique to supplant traditional serological tests for body fluid identification. It was hypothesized that proteomic techniques would surpass the sensitivity and specificity of traditional serological techniques. An automated workflow coupled with protein MS has been developed for the confirmatory identification of five biological fluids. A developmental validation was completed, assessing parameters such as reproducibility, sensitivity, ion suppression, and limit of detection. Implementation was determined through tandem sample processing by MS, traditional serological tests, and standard DNA profiling methods. The MS approach offered superior detection limits while also providing true confirmatory results, producing …

A Review And Evaluation Of Techniques For Improved Feature Detection In Mass Spectrometry Data, Annika R. Tostengard, Rob Smith

Graduate Student Theses, Dissertations, & Professional Papers

Mass spectrometry (MS) is used in analysis of chemical samples to identify the molecules present and their quantities. This analytical technique has applications in many fields, from pharmacology to space exploration. Its impacts on medicine are particularly significant, since MS aids in the identification of molecules associated with disease; for instance, in proteomics, MS allows researchers to identify proteins that are associated with autoimmune disorders, cancers, and other conditions. Since the applications are so wide-ranging and the tool is ubiquitous across so many fields, it is critical that the analytical methods used to collect data are sound.

Data analysis in …

Labilization And Diversification Of Pyrogenic Dissolved Organic Matter By Microbes, Aleksandar I. Goranov, Andrew S. Wozniak, Kyle W. Bostick, Andrew R. Zimmerman, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

With the increased occurrence of forest fires around the world, interest in the chemistry of pyrogenic organic matter (pyOM) and its fate in the environment has increased. Upon leaching from soils by rain events, significant amounts of dissolved pyOM (pyDOM) enter the aquatic environment and interact with microbial communities that are essential for cycling organic matter within the different biogeochemical cycles. To evaluate the bio-reactivity of pyDOM, aqueous extracts of laboratory-produced chars were incubated with soil microbes and the molecular changes to the composition of pyDOM were probed using ultrahigh resolution mass spectrometry (Fourier transform – ion cyclotron resonance – …

Mass Spectral And Chemometric Analysis For The Detection And Identification Of Forensically Relevant Materials, Meghan Grace Appley

Legacy Theses & Dissertations (2009 - 2024)

Forensic science is the application of science to the law which in and of itself covers a substantial number of disciplines. Many of these involve the detection and identification of materials using analytical techniques. Traditional analysis methods include microscopy, spectroscopy and mass spectrometry. The materials encountered by forensic practitioners are ever evolving, resulting in the need to develop new methods to complement conventional techniques to enhance the evidentiary value of the samples. The research presented here shows that novel methods including direct analysis in real time–high-resolution mass spectrometry (DART-HRMS), thermal desorption coupled with gas chromatography-mass spectrometry (TD-GC-MS), solid-phase microextraction (SPME) …

Applications Of Mass Spectrometry To Forensic Entomology : Calliphoridae Species Determination, Monitoring Of Decomposition Volatiles, And Discovery Of Chemical Cues, Justine Elizabeth Giffen-Lemieux

Legacy Theses & Dissertations (2009 - 2024)

Forensic entomology is the study of insects that colonize human/animal wounds and remains and their development for use in legal contexts. It has numerous facets and applications including: estimation of time since death; investigation of neglect/abuse of children and the elderly; and determination of the presence of toxins and drugs as a potential cause of death. In order for the discovered insects to be of forensic utility, accurate species identification is crucial. Current methodologies for species determination rely on the knowledge and expertise of an entomologist; exhaustive taxonomic keys; and access to adequate equipment and facilities; resources which are often …

Application Of Direct Analysis In Real Time-High Resolution Mass Spectrometry To Genus- And Species-Level Differentiation And Identification Of Coral, Jessica Mary Hayes

Legacy Theses & Dissertations (2009 - 2024)

Coral reefs are one of the most biologically diverse ecosystems, and the accurate identification of the species is essential for diversity assessment, species delimitation and conservation. Current species and genus determination approaches are time consuming, resource intensive and can be highly subjective. To explore the hypothesis that the small molecule profiles of coral are species and genus specific, and can be used as a rapid tool to catalogue, classify and identify coral genera and species, the small-molecule chemical fingerprints of coral belonging to the species Acanthastrea echinata, Catalaphyllia jardinei, Duncanopsammia axifuga, Echinopora lamellosa, Euphyllia divisa, Euphyllia paraancora, Euphyllia paradivisa, Galaxea …

Proteome Analysis And Epitope Mapping In A Commercial Reduced-Gluten Wheat Product, Mitchell G. Nye-Wood, Angela Juhasz, Utpal Bos, Michelle L. Colgrave

Research outputs 2014 to 2021

Gluten related disorders, such as coeliac disease, wheat allergy and baker's asthma are triggered by proteins present in food products made from wheat and related cereal species. The only treatment of these medical illnesses is a strict gluten-free diet; however, gluten-free products that are currently available in the market can have lower nutritional quality and are more expensive than traditional gluten containing cereal products. These constraints have led to the development of gluten-free or gluten-reduced ingredients. In this vein, a non-GMO wheat flour that purports to contain “65% less allergenic gluten” was recently brought to market. The present study aims …