Physical Sciences and Mathematics Commons^™

Ambient Ionization - Mass Spectrometry: Advances Toward Intrasurgical Cancer Detection, Alan Keith Jarmusch

Open Access Dissertations

My dissertation research has focused on the development of ambient ionization – mass spectrometry (MS) for clinical measurements, specifically intrasurgical cancer detection. The molecular differences between normal and cancerous tissue were detected via direct tissue analysis in vitro by touch spray ionization (TS) or by analyzing sectioned or smeared tissue using desorption electrospray ionization (DESI). The physical form of the tissue, e.g. in vitro sampling, sectioned, or smeared, was inconsequential in differentiating normal from cancerous tissue; however, the spectra acquired by TS and DESI differed due to differences in ionization processes. We envision that TS-MS and DESI-MS could impact diagnostic …

Preparative Mass Spectrometry Applications In Nanomaterials And Organic Synthesis, Michael Wleklinski

Open Access Dissertations

Preparative mass spectrometry was traditionally a vacuum based experiment where mass selected ion beams were deposited onto surfaces; however, recently ions have been manipulated in the open air to perform accelerated synthesis. The work of this dissertation focuses on the generation of charged ions from microdroplets and their use in organic synthesis and the preparation of atomically precise metal nanoclusters. First the mechanism for charging in the zero volt paper spray will be presented. This works builds a computational model based on the statistical fluctuation of positive and negative charges based on the theory of Dodd. It is found through …

Investigation Of Dynamic Biological Systems Using Direct Injection And Liquid Chromatography Mass Spectrometry, Adam Clayton Swensen

Theses and Dissertations

In biological systems, small changes can have significant impacts. It is, therefore, very important to be able to identify these changes in order to understand what is occurring in the organism. In many cases, this is not an easy task. Mass spectrometry has proven to be a very useful tool in elucidating biological changes even at a very small scale. Several different mass spectrometry based techniques have been developed to discover and investigate complex biological changes. Some of these techniques, such as proteomics, have been through years of development and have advanced to the point that anyone can complete complex …

Mass Spectrometric Characterization Of Remotely Charged Amino Acids And Peptides, Damodar Koirala

Open Access Dissertations

Ion–molecule reactions in a flowing afterglow are used to examine the electronic structure of 3- and 4-pyridinylnitrene-n-oxide radical anions. Reactions with nitric oxide are generally similar to those reported previously for other aromatic nitrene radical anions. In particular, phenoxide formation by nitrogen–oxygen exchange is observed with both isomers. Oxygen atom abstraction by NO is also observed with both isomers. Very significant differences in the reactivity are observed in the reactions of the two isomers with carbon disulfide. The reactivity of the 3-noxide isomer with CS2 is similar to that observed previously for nitrene radical anions, and reactions of the n-oxide …

Novel Analytical Methods Combining Non-Denaturing Chromatography And Mass Spectrometry To Study Biopolymer Structure And Interactions, Khaja Muneeruddin

Doctoral Dissertations

Biotherapeutics, an emerging class of medicines containing biopolymers (e.g., proteins, peptide, and polysaccharides) have been developed for a variety of indications including cancer, autoimmune, genetic, and blood diseases. Among these biopolymers protein therapeutics have been the rapidly growing segment in the pharmaceutical industry. This trend combined with the complexity of proteins has necessitated the development of powerful and robust analytical methods to study their structure and interactions with physiological partners. Mass spectrometry (MS) has become an indispensable tool to analyze various attributes of protein drugs such as profiling of intact mass, amino acid sequencing, and post translational modifications (PTMs). In …

Possible Sources And Impacts Of Biochar Water Extractable Organic Compounds On Aquatic Microorganisms, Cameron Russell Smith

Chemistry & Biochemistry Theses & Dissertations

Smokeless biomass pyrolysis with application of biochar as a soil amendment could be a significant approach for carbon sequestration to possibly control climate change for energy and environmental sustainability. If biochar were to be utilized as a soil amendment and a carbon sequestration agent at Gt C scales, the release of potentially toxic compounds into soils and associated hydrological systems, through soil rainwater runoff and leaching, might have negative consequences, in both agro-ecosystems and aquatic environmental systems. Therefore, the main focus of this dissertation was to study the sources and chemical composition of biochar water extractable (soluble) organic compounds and …

Application Of Electrospray Ionization Mass Spectrometry For Ionic Liquids And Their Biodegradation Products, Sepideh Rahbarirad

Masters Theses

Ionic liquids (ILs) are organic salts with unique physico-chemical properties and are used as green alternatives to volatile organic solvents. ESI-MS is a sensitive technique to detect these stable, permanent ions. My research focused on (1) Identification of biodegradation products of ionic liquids and (2) Multiplexed tandem MS by modulation of ionization efficiency.

Studies, have demonstrated that ILs are toxic to the environment, which makes their biodegradability an important consideration. In this work, metabolites generated during the biodegradation of 1-butyl-3-methylimidazolium chloride (BMIM), a degradation resistant and commonly used ionic liquid, are identified using high performance liquid chromatography-mass spectrometry (LC-MS).

Multiplexed …

Environmental Applications Of Chromatography-Mass Spectrometry, Wisam Abdulabbas Flayyih Al Isawi

Masters Theses

Gas chromatography-mass spectrometry (GC-MS) and liquid chromatographymass spectrometry (LC-MS) are powerful analytical techniques that combine the separation power in a stationary phase with the detection power of mass spectrometry. GCMS and LC-MS have gained dominant positions in identifying and quantifying different analyte species due to their high selectivity, high sensitivity, and high reproducibility.

My research utilizes the analytical power of LC-MS and GC-MS to address two environmental issues: 1) Identification of biodegradation products of the ionic liquid 1- butyl-3-methylimidazolium chloride (BMIMCl) by an activated sludge microbial community using LC-MS and 2) identification and quantification of polycyclic aromatic hydrocarbons (PAHs) in …

Discovery Of Low-Molecular Weight Novel Serum Biomarkers For Diagnosing Preeclampsia And Alzheimer's Disease, Swati Anand

Theses and Dissertations

Preeclampsia (PE), a life threatening pregnancy-related disorder, is characterized mainly by new onset of hypertension and proteinuria after 20 weeks of gestation. Currently, PE cannot be predicted prior to onset of symptoms and there is no cure for the disease. There is a clear value in having biomarkers able, early in a pregnancy, to identify women at risk for PE so that proper treatment therapies could be developed. Although a number of serum candidate markers have been proposed to be altered in PE patients, their use is limited due to poor sensitivity and specificity. Therefore, there is ongoing need for …

The Development Of Peptide Ligands To Target H69 Rrna, Danielle Nicole Dremann

Wayne State University Dissertations

ABSTRACT

THE DEVELOPMENT OF PEPTIDE LIGANDS TO TARGET H69

by

DANIELLE NICOLE DREMANN

December 2015

Advisor: Prof. Christine S. Chow

Major: Chemistry (Biochemistry)

Degree: Doctor of Philosophy

In the development of peptide ligands to target H69, SPPS and ESI MS was used to determine if 1) peptides could bind to modified H69 and 2) if increased affinity for the target RNA could be enhanced with modification. An alanine and arginine scan was synthesized and tested for this determination. Selected peptides were then tested using biophysical techniques such as circular dichroism and isothermal titration calorimetry. An assay was also designed to …

Development Of Direct Analysis In Real Time-High Resolution Mass Spectrometry (Dart-Hrms) And Statistical Analysis Tools For The Identification And Classification Of Psychoactive Plant Drugs, Ashton Danielle Lesiak

Legacy Theses & Dissertations (2009 - 2024)

In current forensic testing, a new pattern is emerging where the drugs that are submitted to crime labs for analysis are no longer restricted to well-characterized substances such as cocaine, heroin and tetrahydrocannabinol (THC). The appearance of new psychoactive substances (NPS) in forensic laboratories, including synthetic alternatives to scheduled substances and plant-based psychotropics, has highlighted issues that traditional analytical methods such as gas chromatography- and liquid chromatography-mass spectrometry impose in the characterization of these samples. These can include lengthy extractions, derivatization steps, pH adjustments and/or a host of other procedures. Since the creation of legislation to address the use of …