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Full-Text Articles in Analytical Chemistry

High Resolution Mass Spectrometry As A Platform For The Analysis Of Polyoxometalates, Their Solution Phase Dynamics, And Their Biological Interactions., Daniel T. Favre Mar 2024

High Resolution Mass Spectrometry As A Platform For The Analysis Of Polyoxometalates, Their Solution Phase Dynamics, And Their Biological Interactions., Daniel T. Favre

Doctoral Dissertations

Polyoxometalates (POMs) are a class of inorganic molecule of increasing interest to the inorganic, bioinorganic and catalytic communities among many others. While their prevalence in research has increased, tools and methodologies for the analysis of their fundamental characteristics still need further development. Decavanadate (V10) specifically has been postulated to have several unique properties that have not been confirmed independently. Mass spectrometry (MS) and its ability to determine the composition of solution phase species by both mass and charge is uniquely well suited to the analysis of POMs. In this work we utilized high-resolution mass spectrometry to characterize V10 in aqueous …


Reactive Chemistries For Protein Labeling, Degradation, And Stimuli Responsive Delivery, Myrat Kurbanov Nov 2023

Reactive Chemistries For Protein Labeling, Degradation, And Stimuli Responsive Delivery, Myrat Kurbanov

Doctoral Dissertations

Reactive chemistries for protein chemical modification play an instrumental role in chemical biology, proteomics, and therapeutics. Depending on the application, the selectivity of these modifications can range from precise modification of an amino acid sequence by genetic manipulation of protein expression machinery to a stochastic modification of lysine residues on the protein surface. Ligand-Directed (LD) chemistry is one of the few methods for targeted modification of endogenous proteins without genetic engineering. However, current LD strategies are limited by stringent amino acid selectivity. To bridge this gap, this thesis focuses on the development of highly reactive LD Triggerable Michael Acceptors (LD-TMAcs) …


Deciphering Protein Higher-Order Structure And Interactions Via Diethylpyrocarbonate Labeling-Mass Spectrometry, Xiao Pan Mar 2022

Deciphering Protein Higher-Order Structure And Interactions Via Diethylpyrocarbonate Labeling-Mass Spectrometry, Xiao Pan

Doctoral Dissertations

The study of protein higher-order structures is vital because it is closely related to the investigation of protein folding, aggregation, interaction and protein therapeutics. Consequently, numerous biochemical and biophysical tools have been developed to study protein higher-order structures in many different situations. The combination of covalent labeling (CL) and mass spectrometry (MS) has emerged as a powerful tool for studying protein structures and offers many advantages over other traditional techniques, such as better structural coverage, high throughput, high sensitivity, and the ability to study proteins in mixtures. This dissertation focuses on diethylpyrocarbonate (DEPC) as an effective CL reagent that can …


Quantitative Imaging Of Tensile Forces At Cell-Cell Junction With Dna-Based Probes, Puspam Keshri Feb 2022

Quantitative Imaging Of Tensile Forces At Cell-Cell Junction With Dna-Based Probes, Puspam Keshri

Doctoral Dissertations

Mechanical forces are an integral part in biology, they regulate several cellular properties, such as morphology, proliferation, migration. These forces are also involved in receptor signaling and the differentiation of different cell types. Different proteins and biomolecules such as cadherin, integrin, notch proteins are essential elements of these processes. Measuring these intercellular forces are challenging considering the minimal intensity (piconewton-level) of these molecular forces. In our lab, we have developed a membrane DNA tension probe (MDTP) that uses a DNA hairpin module to sense tensile forces and has a lipid anchor to modify onto live-cell membranes. The programmability of DNA …


Amyloidogenesis Of Β-2-Microglobulin Studied By Mass Spectrometry And Covalent Labeling, Blaise G. Arden Oct 2021

Amyloidogenesis Of Β-2-Microglobulin Studied By Mass Spectrometry And Covalent Labeling, Blaise G. Arden

Doctoral Dissertations

Amyloid-forming proteins are implicated in a number of debilitating diseases. While many amyloid-forming proteins are well studied, the early stages of amyloidosis are still not well understood on a molecular level. Covalent labeling, combined with mass spectrometry (CL-MS), is uniquely well suited to provide molecular-level insight into the factors governing the early stages of amyloidosis. This dissertation leverages CL-MS techniques to examine the early stages of β-2-microglobulin (β2m) amyloidosis. β2m is the protein that forms amyloids in the condition known as dialysis-related amyloidosis. An automated CL-MS technique that uses dimethyl(2-hydroxy-5-nitrobenzyl) sulfonium bromide as a labeling reagent was developed and used …


Investigating The Accumulation, Sub-Organ Distribution, And Biochemical Effects Of Nanomaterials Using Mass Spectrometry, Kristen Nicole Sikora Dec 2020

Investigating The Accumulation, Sub-Organ Distribution, And Biochemical Effects Of Nanomaterials Using Mass Spectrometry, Kristen Nicole Sikora

Doctoral Dissertations

Gold nanoparticles (AuNPs) are attractive materials for use in various biomedical applications, such as therapeutic delivery, due to their unique chemical properties and modular tunability. Mass spectrometry methods, including laser desorption/ionization mass spectrometry (LDI-MS) and inductively coupled plasma mass spectrometry (ICP-MS) have been successfully used to evaluate the distribution of AuNPs in complex biological systems. As new AuNP-based materials are developed for applications in therapeutic delivery, it is essential to simultaneously develop analytical techniques that can comprehensively assess their behavior in vivo. In this dissertation, novel mass spectrometric methods have been developed and utilized to evaluate the uptake, distribution, …


Structural Analysis Of Protein Therapeutics Using Covalent Labeling – Mass Spectrometry, Patanachai Limpikirati Jul 2020

Structural Analysis Of Protein Therapeutics Using Covalent Labeling – Mass Spectrometry, Patanachai Limpikirati

Doctoral Dissertations

Using mass spectrometry (MS) to obtain information about a higher order structure of protein requires that a protein’s structural properties are encoded into the mass of that protein. Covalent labeling (CL) with reagents that can irreversibly modify solvent accessible amino acid side chains is an effective way to encode structural information into the mass of a protein, as this information can be read-out in a straightforward manner using standard MS-based proteomics techniques. The differential reactivity of proteins under two or more conditions can be used to distinguish protein topologies, conformations, and/or binding sites. CL-MS methods have been effectively used for …


Characterization Of Biodistribution Of Transferrin And Receptor Binding Mechanism By Mass Spectrometry, Hanwei Zhao Mar 2020

Characterization Of Biodistribution Of Transferrin And Receptor Binding Mechanism By Mass Spectrometry, Hanwei Zhao

Doctoral Dissertations

Protein-based therapeutics have emerged as a key driver of rapid growth in drug development pipelines. However, developing such protein drugs is not straightforward in most cases, the existence of physiological barriers greatly restricts the efficient delivery of many therapeutic molecules, and therefore limits their clinical applications. A promising way to address this challenge takes advantage of certain transport protein which can effectively across and enhance the permeability of these barriers, such as transferrin (Tf) which can be internalized by malignant cells and cross physiological barriers via transferrin receptor (TfR)-mediated endocytosis and transcytosis. However, developing such products is impossible without successfully …


Covalent Labeling-Mass Spectrometry For Characterizing Protein-Ligand Complexes, Tianying Liu Feb 2020

Covalent Labeling-Mass Spectrometry For Characterizing Protein-Ligand Complexes, Tianying Liu

Doctoral Dissertations

This dissertation focuses on applying covalent labeling (CL) and mass spectrometry (MS) for characterizing protein-ligand complexes. Understanding protein-ligand interactions has both fundamental and applied significance. Covalent labeling is a protein surface modification technique that selectively modifies solvent-exposed amino acid side chains of proteins. A covalent bond is formed between the functional groups of labeling reagent and protein’s side chain. One of the key factors that affects CL reactivity is a side chain’s solvent accessibility. Ligand binding protects residues on the protein surface from being labeled, and residues involved in ligand binding can be indicated via decreases in labeling extents. The …


Characterization Of Β-2-Microglobulin Pre-Amyloid Oligomers And Their Role In Amyloid Inhibition, Tyler M. Marcinko Oct 2019

Characterization Of Β-2-Microglobulin Pre-Amyloid Oligomers And Their Role In Amyloid Inhibition, Tyler M. Marcinko

Doctoral Dissertations

In dialysis patients, β-2 microglobulin (β2m) can aggregate and eventually form amyloid fibrils in a condition known as dialysis-related amyloidosis, which deleteriously affects joint, bone, and organ function, and eventually causes organ failure. To understand the early stages of the amyloid assembly process, we have employed a series of biophysical tools including chromatography, spectroscopy, and most especially, native electrospray ionization (ESI) together with ion mobility mass spectrometry (IM-MS) to study soluble pre-amyloid oligomeric species. We have also collaborated and integrated computational modeling to help better understand and rationalize the structural basis behind oligomerization. Recently, several small molecules have been identified …


Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao Oct 2019

Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao

Doctoral Dissertations

Mass spectrometry (MS) has played an increasingly prominent role in proteomics and structure biology because it shows superior capabilities in identification, quantification and structural characterization of proteins. To realize its full potential in protein analysis, significant progress has been made in developing innovative techniques and reagents that can couple to MS detection. This dissertation demonstrates the use of polymeric supramolecular assemblies for enhanced protein detection in complex biological mixtures by MS. An amphiphilic random co-polymer scaffold is developed to form functional supramolecular assemblies for protein/ peptide enrichment. The influences of charge density and functional group pKa on host-guest interactions …


Mechanistic Studies Of Proton Gradient-Driven Protein Translocation By Droplet-Interface Bilayer Techniques, En-Hsin Lee Jul 2017

Mechanistic Studies Of Proton Gradient-Driven Protein Translocation By Droplet-Interface Bilayer Techniques, En-Hsin Lee

Doctoral Dissertations

Transmembrane proton gradient plays a fundamental role in protein translocation across cellular membranes, including the transport of secreted enzymes from bacterial pathogens into host cells. Much attention has been devoted to understanding the machinery of such delivery and how it functions. Over the past decade, translocation of anthrax toxin has been widely studied not only because of its central role in the deadly pathogenesis of Bacillus anthracis, but also because that it is one of the most tractable toxins and thus serves as an attractive model for studying the translocation machinery that is dependent on proton gradient across membrane. …


The Application Of Hydrogen/Deuterium Exchange And Covalent Labeling Coupled With Mass Spectrometry To Examine Protein Structure, Nicholas B. Borotto Mar 2016

The Application Of Hydrogen/Deuterium Exchange And Covalent Labeling Coupled With Mass Spectrometry To Examine Protein Structure, Nicholas B. Borotto

Doctoral Dissertations

Thorough insight into a protein’s structure is necessary to understand how it functions and what goes wrong when it malfunctions. The structure of proteins, however, is not easily analyzed. The analysis must take place under a narrow range of conditions or risk perturbing the very structure being probed. Furthermore, the wide diversity in size and chemistry possible in proteins significantly complicates this analysis. Despite this numerous methods have been developed in order to analyze protein structure. In this work, we demonstrate that mass spectrometry (MS)-based techniques are capable of characterizing the structure of particularly challenging proteins. This is done through …


Utilizing In Silico And/Or Native Esi Approaches To Provide New Insights On Haptoglobin/Globin And Haptoglobin/Receptor Interactions, Ololade Fatunmbi Nov 2015

Utilizing In Silico And/Or Native Esi Approaches To Provide New Insights On Haptoglobin/Globin And Haptoglobin/Receptor Interactions, Ololade Fatunmbi

Doctoral Dissertations

Haptoglobin (Hp), an acute phase protein, binds free hemoglobin (Hb) dimers in one of the strongest non-covalent interactions known in biology. This interaction protects Hb from causing potentially severe oxidative damage and limiting nitric oxide bioavailability. Once Hb/Hp complexes are formed, they proceed to bind CD163, a cell surface receptor on macrophages leading to complex internalization and catabolism. Myoglobin, (Mb) a monomeric protein, that is normally found in the muscle but can be released into the blood in high concentrations during myocardial injury, is homologous to Hb and shares many conserved Hb/Hp interface residues. Both monomeric Hb and Mb species …


Protein Behavior Directed By Heparin Charge And Chain Length, Burcu Baykal Minsky Aug 2014

Protein Behavior Directed By Heparin Charge And Chain Length, Burcu Baykal Minsky

Doctoral Dissertations

Glycosaminoglycans (GAGs), highly charged biological polyelectrolytes, are of growing importance as biomaterials and pharmaceutical drugs due to their immense range of physiological functions. They bind to many proteins; however, the degree of structural selectivity in GAG-protein interactions is largely unknown .Our studies have focused on the importance of heparin (a model GAG) charge and chain length in protein binding in order to explore its potential applications in biofunctional tissue scaffold materials, as polysaccharide drugs in anticoagulation, and as inhibitory agents in protein aggregation. We used electrospray ionization mass spectrometry, capillary electrophoresis, size exclusion chromatography, dynamic/static light scattering and electrostatic protein …