Physical Sciences and Mathematics Commons^™

Chemical Investigations Of Diabetes Mellitus, Malaria, And Castrate-Resistant Prostate Cancer, Maggie Sparks Lookadoo

Masters Theses

This work studies a variety of molecules and the systems they are involved in to further understand disease and treatment of diabetes mellitus, malaria, and castrate resistant prostate cancer. The first system studied, diabetes mellitus, involves synthesis of 5 different steroidal compounds, while the other two systems, malaria and castrate-resistant prostate cancer, apply mass spectrometric-based untargeted metabolomics to study both known metabolites and unknown spectral features.

Diabetes mellitus is a result of the dysfunction and death of islet beta cells caused by the transcription of pro-inflammatory cytokines resulting in reduced insulin secretion and uncontrollable blood glucose levels. Glucocorticoids can reduce …

Development Of A Miniaturized Ambient Glow Discharge Ionization Source And Its Application In Elemental And Molecular Analysis, Xinyan Zhang

All Dissertations

Since the liquid sampling-atmospheric pressure glow discharge (LS-APGD) was first developed as an excitation source for atomic emission spectroscopy, it has been improved upon and demonstrated as an ionization source for elemental mass spectrometry, molecular mass spectrometry, and ambient desorption mass spectrometry. Multiple functions coming from one package allowed the LS-APGD to hold a unique position among all atmospheric pressure glow discharges. It also has the capabilities to work with different sample forms including liquids, bulk solids, and solution residues. The high salt/matrix tolerance reduces sample prep work and thus provides convenience for its potential use as a field-Based ionization …

Studying Nanoparticle/Cell And Nanoparticle/Biosurface Interaction With Mass Spectrometry, Singyuk Hou

Masters Theses

Nanoparticles (NPs) have been used widely in various fields ranging from biomedical applications to life science due to their highly tunable properties. It is essential to understanding how NPs interact with biological systems of interest, therefore, analytical platforms to efficiently track NPs from cell to animal level are essential. In this thesis, laser desorption ionization mass spectrometry (LDI-MS) and inductively-coupled plasma mass spectrometry (ICP-MS) has been developed and applied to quantify NP/cell and NP/biological surface interactions. These two methods provide fast, label-free and quantitative analysis. New capability of LDI-MS to differentiate cell surface-bound and internalized NPs were established and ICP-MS …

From Solution Into The Gas Phase: Studying Protein Hydrogen Exchange And Electrospray Ionization Using Molecular Dynamics Simulation, Robert G. Mcallister

Electronic Thesis and Dissertation Repository

Here, we apply Molecular Dynamics (MD) simulations to investigate fundamental aspects of structural mass spectrometry (MS). We first examine microscopic phenomena underlying Hydrogen/Deuterium exchange (HDX). HDX interrogates structural dynamics of proteins by measuring the rate of Deuterium uptake into backbone amides. We perform microsecond MD simulations on ubiquitin to investigate this process. We find that HDX protection often cannot be explained by H‑bonding or solvent accessibility considerations. These findings caution against non-critical use of HDX data in structural contexts. We next use MD to examine the Electrospray ionization (ESI) mechanism of proteins. ESI is a soft ionization technique resulting in …

Development And Application Of Mass Spectrometry-Based Biophysical Approaches, Ying Zhang

Arts & Sciences Electronic Theses and Dissertations

Mass spectrometry (MS)-based biophysical approaches are new "tools" for protein characterization owing to its capability to analyze proteins and protein complexes that range in molecular weight from kDa to MDa. Protein characterization requires more than identifying the primary structure. More importantly, protein high order structures (i.e., secondary, tertiary and quaternary structures) are needed for biological studies. MS has become the major tool in studies of protein primary structure and post translational modifications (PTMs) over the past two decades. Because MS has high sensitivity and fast turnaround, more and more biophysical approaches rely on MS to generate information for protein higher …

Noncovalent Interactions Between Alkali Metal Cation And Aza/Thia-Crown Macrocycles: Mass Spectrometric Techniques And Theoretical Studies, Calvin A. Austin

Wayne State University Dissertations

Macrocyclic complexes have been useful in understanding many systems encountered in biology, along with having widespread use in analytical, pharmaceutical, and synthetic chemistry. My goal was to provide a quantitative experimental and theoretical description of cation-aza-crown and thia-crown ether interactions with alkali metal cations. Infrared multiple photon dissociation (IRMPD) action spectroscopy and energy-resolved collision-induced dissociation (CID) techniques were used in conjunction with theoretical electronic structure calculations to characterize the structures, binding interactions, and stability of cation-aza-crown ether interactions. Quantum chemical calculations at several levels of theory were employed to characterize the structures and stabilities of the isolated cations and aza-crown …

Development Of An Extraction Method For The Mass Spectral Analysis Of Organic Gunshot Residue From Clothing, Brent Casper

Theses and Dissertations--Chemistry

This dissertation will focus on the extraction of volatile organic compounds associated with gunshot residue from articles of clothing, followed by analysis with mass spectrometry. During the discharge of a weapon, a cloud of volatile organic gunshot residue (OGSR) is dispersed around a firearm. This will create a high probability of transfer between the OGSR and the clothing of individuals who are near a discharged weapon.

The first part of this dissertation will be the development of a method for removal of volatile OGSR from articles of clothing. Extraction of OGSR will be completed by solid phase microextraction (SPME), followed …

Determination Of The Structure Of Sphingomyelin By Tandem Mass Spectrometry And Matrix - Assisted Laser Desorption/Ionization, Antonio Ganios

Williams Honors College, Honors Research Projects

Mass spectrometry is a method that uses masses to determine the structure of a compound. This is completed by first charging the compound until it is a cation or anion, and then its molecular weight can be determined by measuring a mass to charge ratio. The focus of this study was determination of sphingomyelin’s structure. The purpose of this was that sphingomyelin has been shown to play a critical role in many biological pathways and being able to identify this lipid could prove to be beneficial for preventative medicine. Utilizing electrospray ionization (ESI) Quadruple-Time-of-flight (Q-TOF) mass spectrometry on a Waters …

Analytical Method Development For The Detection And Analysis Of Protein Carbonyls, Chelsea M. Coffey

Theses and Dissertations

Oxidative stress can result in changes to many biomolecules and also affect their activities. We are interested in protein carbonylation, a type of unnatural oxidation which has been associated with numerous degenerative disease states and is also a consequence of the natural aging process. Protein carbonyls are stable species, but countless analytical barriers exist in terms of their identification. Thus, the main goal of this work was to develop and optimize analytical methods that could be used to help us better understand which, where, and how proteins are being carbonylated.

Initial studies involved method validation for carbonylating, tagging, and enriching …