Physical Sciences and Mathematics Commons^™

Artemisinin And Its Derivatives Reactions: Characterization Of The Reaction Products Using Lc/Tof Ms, Kogila Vijayan

Theses and Dissertations

Artemisinin (ART) is a sesquiterpene lactone and a popular malaria drug with potential anticancer properties. In this work, LC/TOF MS was used to investigate the reaction of ART with DNA bases and estradiol. ART-deoxyadenosine and ART-deoxycytidine interactions were studied in the presence of Fe (II) ions. ART-deoxyadenosine and ART-deoxycytidine reaction mixtures gave chromatographic signatures that remained unchanged at room temperature but grew after incubation at 37°C. The change in temperature from room temperature to 37°C was the main driver of adduct formation in these reactions. ART was found to react with Fe (II) ions as observed from several new chromatographic …

Speciated Isotope Dilution Mass Spectrometry In Combination With Thor’S Hammer Metaspike Technology For The Assessment Of Low-Level Biomarkers For Human Health Evaluation, Ashley Ebert

Electronic Theses and Dissertations

Our research team has been focused on quantifying important biological analytes in human blood samples to delineate the biochemical processes underlying certain states of dysfunction and evaluate treatment efficacy. These efforts have been guided by laboratory measurements with the input of medical experts. Speciated isotope dilution mass spectrometry (SIDMS) explained in detail in EPA Method 6800 has been successfully applied in the quantification of an important biomarker analyte for immune function and detoxification processes: glutathione. Past research has proven the molecule a biomarker for autism spectrum disorder (ASD) in the form of the reduced/oxidized glutathione (GSH/GSSG) ratio, and literature has …

Evaluation And Improvement Of Capillary Microextraction Of Volatiles Coupled To Gas Chromatography-Mass Spectrometry For The Analysis Of Ignitable Liquid Residues In Fire Debris, Michelle Nikole Torres

FIU Electronic Theses and Dissertations

A key aspect of fire debris analysis is the ability to extract the remnants of an ignitable liquid from a matrix with a high degree of reliability and sensitivity. Although there are several robust, standardized methods, there is no single technique universally applicable to casework. In this work a novel extraction technique – Capillary Microextraction of Volatiles (CMV) – has been applied, for the first time, for ignitable liquid residue (ILR) extraction. A 20-minute dynamic sampling laboratory protocol from traditional 1 L paint cans was established and optimized based upon ASTM guidelines. The development of new adsorption phases for CMV …

Detection Of Benzotriazole And Related Analogues In Surface Samples Collected Near An Ohio Airpark, Clara Leedy

Browse all Theses and Dissertations

Benzotriazoles are a class of contaminant of emerging concern which are commonly used as anticorrosive agents in aircraft deicer and anti-icing fluids (ADAFs). The analogues 1H-benzotriazole (BTZ), 4-methyl-1H-benzotrizole (4m-BTZ), and 5-methyl-1H-benzotriazole (5m-BTZ) are commonly found in environmental occurrence together. The two methylated isomers, collectively known as tolytriazole (TTZ), have different toxicity and stability. These contaminants are highly water soluble and resistant to biodegradation, making them persistent through water treatment. Benzotriazoles have been detected worldwide; this investigation focuses on monitoring three sites near a small airpark in Wilmington, Ohio. Two sites that receive runoff from the airpark, Lytle Creek and Indian …

The Formation Of Prenucleation Clusters For Calcium Fluoride, Taylor M. Muterspaw

Browse all Theses and Dissertations

There have been limited studies on the analysis of the nucleation and precipitation behind calcium fluoride. Earlier studies support a nucleation mechanism in agreement to classical nucleation theory (CNT) in which a surface nucleation mechanism is required for calcium fluoride. This experiment devised using the ISE method to calcium fluoride to find evidence of a nucleation mechanism like that of calcium carbonate (prenucleation cluster pathway). The potential and pH were recorded versus time and the potential data was converted to nCa2+ data of free calcium ions. It was determined that there was evidence of a similar nucleation mechanism for calcium …

Novel Approaches To The Determination Of Toxic Metals In Industrial Waste And Soil Extracts, Garrett Bruce Finn

Theses and Dissertations

Abstract:Because of their environmental impact, the contamination and migration of heavy metals is an important field of study. In this thesis, two novel methods for measuring toxic metals over a broad concentration range in complex matrices were successfully developed and applied to authentic samples. This research focused on toxic metals in two disparate environments: industrial effluent and soil. The primary work reported in this research focused on developing a Sequential Injection Analysis (SIA) process monitor to measure metals in industrial process waste streams in near real-time. Molecular Absorption Spectroscopy was used to determine levels of Zn and several other metals. …

Review Of Student-Built Spectroscopy Instrumentation Projects, Michelle L. Kovarik, Julia R. Clapis, K. Ana Romano-Pringle

Faculty Scholarship

Copyright © 2020 American Chemical Society and Division of Chemical Education, Inc. One challenge of teaching chemical analysis is the proliferation of sophisticated, but often impenetrable, instrumentation in the modern laboratory. Complex instruments, and the software that runs them, distance students from the physical and chemical processes that generate the analytical signal. A solution to this challenge is the introduction of a student-driven instrument-building project. Visible absorbance spectroscopy is well-suited to such a project due to its relative simplicity and the ubiquity of absorbance measurements. This Article reviews simple instructor- A nd student-built instruments for spectroscopy, providing an overview of …

Elemental Composition And Arsenic Speciation Analysis Of Processed Seafood Products Using Atomic Spectrometric Techniques, Austin A. Roberts

Legacy Theses & Dissertations (2009 - 2024)

Arsenic (As) is a widely known toxic element that is highly ubiquitous and has been detected in soil, sediment, naturals waters, the atmosphere, and in organisms of the 5 kingdoms. The toxicity of As however, is dependent on the molecular form in which it takes as well as the route of exposure. For the general population, exposure to As mainly takes place via ingestion of food and water, which have led to numerous studies investigating As and it’s various species in these matrices. Seafood is one of the major sources of dietary exposure to As and has thus led to …

The Forensic Analysis Of Children's Temporary Tattoos, Erika Bravo

Student Theses

While children’s temporary tattoos have been produced since the 20th century, there are few scientific studies that have evaluated their physical and chemical characteristics. Therefore, this thesis is a preliminary study done to evaluate the composition of children’s temporary tattoos and consider the importance of such traces in a forensic content.

Colored regions in children’s temporary tattoos, such as red, pink, yellow and orange, were found to fluoresce with the use of an alternative light source while the use of microscopy led to the identification of different printing patterns between temporary tattoos. However, limitations in the ability to determine the …

Interrogation Of Ion-Neutral Complexes By Trapped Ion Mobility-Mass Spectrometry And Theoretical Calculations, Alan A. Mckenzie Coe

FIU Electronic Theses and Dissertations

In the present study, the fundamentals of molecular ion trapping and the application of trapped ion mobility spectrometry coupled to mass spectrometry (TIMS-MS) to the separation and identification of molecular components in complex mixtures are shown. In particular, ion-neutral complexes lifetimes, relative stability, binding energies and candidate structures are described for common explosives during TIMS-MS, as well as the effect of the micro-environment, during complex sample analysis. A novel TIMS-MS workflow was developed for the detection of both inorganic residues (IGSR; inorganic gunshot residues) and organic residues (OGSR) of firearm discharge residue from skin swabs, capable of high specificity and …

Multidimensional Mass Spectrometry Of Chemonic™ Ccg-6 Nonionic Surfactant With Separation By Polarity And Shape, Charles Johnson

Williams Honors College, Honors Research Projects

Chemonic™ CCG-6 surfactant is a water-soluble poly(ethylene glycol) (PEG) conjugated alkyl glyceride emollient. This surfactant exists as a complex mixture of a glycerol cores conjugated with poly(ethylene glycol) branches (PEGylation) that were partially esterified with caprylic (C8) and capric (C10) acids. These may be esterified on one, two, or all three arms of the glyceride. The architecture of the structures in this mixture was studied using multidimensional mass spectrometry (MS). Mass spectrometry was interfaced with ultra-performance liquid chromatography (UPLC) and ion mobility (IM) separation. The mixture was separated by reversed-phase LC, oligomers of the star-branched polymer were separated according to …

Investigating Non-Targeted Screening And Accurate Quantitation Of Trace Surface Water Contaminants Using High-Resolution Mass Spectrometry, Lucas M. Morrison

Electronic Thesis and Dissertation Repository

The human impact on surface water is a growing concern and the chemical surveying of contaminants including pharmaceuticals and pesticides is currently lacking. Neonicotinoids in particular, are among the most widely used insecticides that have prompted environmental concern and require monitoring. Chemical contaminants in environmental water samples are commonly analyzed by targeted tandem mass spectrometry. However, this requires a prior knowledge of the contaminants in the area of interest. Here, surface water samples were screened by utilizing optimized data-independent acquisition (DIA) methods and the spectra were databased for future retrospective analysis. This circumvents the requirement for target analytes prior to …

Novel Mass Spectrometry Methods For The Analysis Of Covalent And Non-Covalent Protein Structures And Their Influence On The Functions Of Therapeutic Proteins, Jake Pawlowski

Doctoral Dissertations

Biotherapeutics consist of biopolymers (proteins, polysaccharides, DNA, and RNA) that are used to treat a wide range of conditions from cancer to autoimmune disease to enzyme replacement. In recent years biotherapeutics have experience tremendous growth due to advances in technology and our understanding of human biology. They are very important to modern medicine due to their ability to treat diseases which are unable to be treated with small molecule-based drugs. Unlike small molecule drugs which are synthetically produced, biotherapeutics are expressed inside cells. Produced biotherapeutics are not made up of a single homogenous population but instead a population of highly …

Conformational Dynamics Of Biomolecules By Trapped Ion Mobility Spectrometry Dynamics, Juan Camilo Molano-Arévalo

FIU Electronic Theses and Dissertations

One of the main goals in structural biology is to understand the folding mechanisms and three-dimensional structure of biomolecules. Many biomolecular systems adopt multiple structures as a function of their microenvironment, which makes them difficult to be characterized by traditional structural biology tools (e.g., NMR, X-ray crystallography). As an alternative, complementary tools that can capture and sample multiple conformations needed to be developed. In the present work, we pioneered the application of a new variant of ion mobility spectrometry, trapped ion mobility spectrometry (TIMS), which provides high mobility resolving power and the possibility to study kinetically trapped intermediates as a …

Discovery And Targeted Monitoring Of Biomarkers Using Liquid Chromatography, Ion Mobility Spectrometry , And Mass Spectrometry, Kendra J. Adams

FIU Electronic Theses and Dissertations

The complexity of biological matrices makes the detection and quantification of compounds of interest challenging. For successful targeted or untargeted identification of compounds within a biological environment, the use of complementary separation techniques is routinely required; in many situations, a single analytical technique is not sufficient. In the present dissertation, a multidimensional analytical technique was developed and evaluated, a combination of new sample preparation/extraction protocols, liquid chromatography, trapped ion mobility and mass spectrometry (e.g., LC-TIMS-MS and LC-TIMS-MS/MS). The performance of these techniques was evaluated for the detection of polybrominated diphenyl ethers metabolites, polychlorinated biphenyls metabolites in human plasma, opioid metabolites …

Chemical And Physical Studies Of Charge Transfer Excited States Of Ruthenium Complexes With Aromatic Ligands, Marim Khalifa Alnaed

Wayne State University Dissertations

The 3MLCT excited states generated from tris-bipyridineruthenium(II), [Ru(bpy)3]2+ and related complexes was ionized by 405 nm irradiation in ambient, acidic aqueous solutions. The photoionization product was Ru(bpy)3]3+ and an electron with a quantum yield of about 0.040.02 in 0.5 M acid. However, 532 nm radiation does not induce photoionization, and it generates the 3MLCT excited state that can be photoionized by 405 nm irradiation. The proton is a very good electron scavenger, and the rate of phoionization of the 3MLCT excited state was determined to be acid dependent and it increased about ten-fold for acid concentrations beween 0.001 and 4 …

Development Of Bioanalytical Methods For Quantitative Measurement Of Anticancer Agents, Sandeep R. Kunati

ETD Archive

The ever-growing need to develop new anticancer agents due to increased incidence of cancer and its recurrence has led to a broad range of investigational efforts in anticancer research. Drug discovery and development processes involve evaluations of pharmacokinetic and pharmacodynamic parameters of potential drug candidates in order to assess their safety, toxicity, and efficacy profiles. By providing sensitivity, assay precision, reliability, and high-throughput, mass spectrometry has become an indispensable tool in quantitative and qualitative analysis, from early-stage drug discovery and development processes to routine laboratory analysis. Development of bioanalytical methods requires knowledge of separation science with instrumentation, data interpretation and …

Quantitative Analysis Of Bleomycin In Rat Plasma By Lc-Ms/Ms, Huawen Li

ETD Archive

Bleomycin is the most commonly used compound in its group of antineoplastic drugs. It works on tumor cells by single and double stranded DNA cleavage after its activation, in which it blocks tumor cells’ DNA replication or transcription activities to inhibit tumor cells’ growth. Bleomycin sulfate (Blenoxane) is the most popular preparation used in clinical research, and contains Bleomycin fractions of A2 and B2, which causes difficulties in quantitative analysis. This work uses the metal chelating property of Bleomycin as an advantage to simplify and improve sensitivity of existing quantitative methods. Copper was spiked in excess to plasma samples, followed …

Advances In Chemistry, Part I: Noise, Calibration, And Educational Advances In Analytical Chemistry. Part Ii: Safety Oversight In Chemical Journals, Lauren E. Grabowski

Theses and Dissertations

Part I:

The accuracy and precision of the results of any chemical analysis depends on the calibration graph and its associated systematic and random errors. Least squares regression generally treats all data with equal weights. A weighted least-squares fit is an improvement but requires knowledge of the imprecision in each point of the calibration graph. The imprecision is not easy to estimate with high confidence because of the large number of replicates needed.

The imprecision depends on the types and magnitudes of the sources of noise. We characterized the noise sources in ICP-OES and UV/Vis and developed a model that …

Using Nucleotide Analogs As Biochemical Probes To Evaluate The Mechanisms Involved In Translesion Replication By A High Fidelity Dna Polymerase, Anvesh Dasari

ETD Archive

Translesion DNA synthesis (TLS) allows DNA polymerases to incorporate nucleotides opposite and beyond damaged DNA. This activity is an important risk factor for the initiation and progression of genetic diseases including cancer. My study evaluates the ability of a high-fidelity DNA polymerase to perform TLS with 8-oxo-guanine, a pro-mutagenic DNA lesion formed by reactive oxygen species. Using modified purine and non-natural indole analogs as biochemical probes, I have evaluated the influence of desolvation, hydrogen bonding interactions, and shape complementarity towards nucleotide binding and incorporation opposite the miscoding lesion 8-oxo-guanine by the high fidelity gp43exo- DNA polymerase. In Chapter II, I …

Qualitative Analysis For The Characterization And Discrimination Of Printing Inks, Rhett J. Williamson

FIU Electronic Theses and Dissertations

Improvements in printing technology and the wide accessibility of advanced printers has resulted in an increase in counterfeiting. Of particular interest to forensic document examiners, ink analysis of security documents has emerged as an important tool for the analysis, comparison, and association of inks to a potential production source. In this study, methods were developed for Py-GC/MS, ATR-FTIR, DART-MS, and MALDI-MS analyses of printing inks of four classes: 78 inkjet inks, 76 toners, 79 offset inks, and 86 intaglio inks in order to generate information on the organic chemical characterization of the inks to determine the ability to associate and …

The Function Of Renalase, Brett Allen Beaupre

Theses and Dissertations

Renalase was originally reported to be an enzyme secreted into the blood by the kidney to lower blood pressure and slow heart rate. Despite multiple reports claiming to confirm this activity in vivo there has been considerable discord in regards to the reaction catalyzed by renalase. The structural topology of renalase resembles that of known flavoprotein oxidases, monooxygenases and demethylases, but the conserved active site residues are unique to renalase. It has been reported that the catalytic function of renalase is to oxidize circulating catecholamines, however in vitro studies have failed to demonstrate a catalytic activity in the presence of …

Development Of A Primary Ion Column For Mass Spectrometry-Based Surface Analysis, Raul A. Villacob

FIU Electronic Theses and Dissertations

Secondary Ion Mass Spectrometry (SIMS) is a powerful technique for high spatial resolution chemical mapping and characterization of native surfaces. The use of massive cluster projectiles has been shown to extend the applicable mass range of SIMS and improve secondary ion yields 100 fold or beyond. These large projectiles however, present a challenge in terms of focusing due to the initial spatial and kinetic energy spreads inherent to their generation. In the present work, we describe the development and construction of a novel primary ion (PI) column employing a gold nanoparticle – liquid metal ion source (AuNP-LMIS) and the coupling …

Development Of Novel Analytical Methods With The Aim Of Forensic Analyte Detection Using Ultra-Thin Layer Chromatography, Surface Enhanced Raman Spectroscopy, And Magneto-Elastic Wire Sensing, Nichole Ann Crane

Doctoral Dissertations

The purpose of this dissertation is to develop analytical methods that aid in the detection of forensic analytes. Forensic analytes require methods with increased sensitivity and low limit of detection capabilities. Improvements in separation techniques, surface enhanced Raman spectroscopic techniques, and wire-less gas sensing can each assist in the detection of trace evidence.

When surface enhanced Raman is coupled with thin-layer chromatography a mixture of compounds can be separated and transferred to a metal substrate to be detected using Raman spectroscopy. Surface enhanced Raman scattering enhances the Raman signal intensity by placing a metal substrate in close proximity to an …

Building And Optimizing A Spectroelectrochemical System For The Study Of Shewanella Putrefaciens, Jonathan Muscolino

Master's Theses

Shewanellaceae are among the most widely studied electroactive microorganisms. This study reports on Shewanella putrefaciens under anaerobic conditions during applied potential while monitored by spectroscopy. The attachment of the microbe Shewanella putrefaciens onto an indium tin oxide electrode was found to occur after 2 hr of +0.2 V applied potential. Microbial detachment occurred with a 5 mV/s scan rate cyclic voltammogram from +0.2 V to -0.5 V to +0.2 V. This was confirmed through use of a spectroelectrochemical apparatus utilizing a standard 3 electrode setup with evanescent wave spectroscopy.

Profiling Cell Surface Sialylation And Desialylation Dynamics Of Immune Cells, Dan Wang

ETD Archive

Sialic acids (SAs) are a diverse family of naturally occurring 2-keto-3-deoxy-nononic acids that are involved in a wide range of biological processes, including early fetal development, cellular recognition, and utilization by microbes. While it is clear that cell surface SAs are highly involved in the immune system, the sialylation status of individual immune cells and functions are still unknown. In this study, I combined the newly developed LC-MS/MS methods with flow cytometry and confocal microscopy to systematically study the sialylation and desialylation dynamics of macrophages at different conditions.

First, I developed an accurate LC-MS/MS method to quantify free SA in …

Development And Validation Of Uplc/Ms/Ms Methods For Quantification Of Gangliosides In The Clinical Study Of Ganglioside Gm3 Synthase Deficiency, Qianyang Huang

ETD Archive

Gangliosides are a large subclass of glycosphingolipids that structurally characterized by the addition of mono- or poly-sialyated carbohydrate moieties onto the ceramide scaffold. They are presented at significant abundance in the central nervous system of vertebrates. Their interactions with trans-membrane receptors, especially receptor tyrosine kinase, are believed to play critical roles in modulating signal transduction events during cell proliferation, differentiation, migration, and adhesion. Furthermore, the disruption and dysfunction on their metabolism have been found to be associated with various neurodegenerative disorders, such as Alzheimer disease, Parkinson’s disease, and GM3 synthase deficiency. GM3 synthase deficiency (GSD) is a newly identified neurological …

Application Of Advanced Analytical Technologies To Drug Development Studies And Cancer Detection, Ramakrishna Reddy Voggu

ETD Archive

In the past decade, bioanalytical method development has become an integral part of the clinical diagnosis, biomarker discovery, and drug discovery and development. The new and emerged bioanalytical techniques allow the quantitative and qualitative analysis of bio molecules with remarkably high sensitivity and specificity. Specifically, these bioanalytical methods based on LC-MS and methylation-specific PCR are well suited for detecting low-abundance metabolites in various biological fluids and DNA in plasma and tissues for biomarker investigation. They offer great clinical promise for early disease diagnosis and therapeutic intervention. This dissertation broadly organized into two parts, part one talks about the application of …

Capillary-Channeled Polymer Fibers As Stationary Phases For Protein Chromatography, Marissa Pierson

All Theses

Capillary-channeled polymer (C-CP) fibers have been studied in this laboratory as stationary phases for protein separations in high-performance liquid chromatography (HPLC). C-CP fibers are uniquely shaped so as to include eight continuous capillary-channels which interdigitate once packed into a column. The packed column resembles a monolithic structure of unobstructed flow through capillary channels which reduces backpressure and increases linear velocity, reducing separation time. Fibers are effectively nonporous with respect to macromolecules, resulting in fast mass transfer and high sample recovery. C-CP fibers made from polypropylene (PP) yield a fairly homogenous hydrophobic surface suitable for reversed phase (RP) chromatography. In a …

Circular Dichroism Spectroscopy In The Undergraduate Curriculum, Adam Urbach

Adam R Urbach

Circular dichroism spectropolarimetry (CD) is a method of optical spectroscopy that seems in most practical ways like UV−visible spectroscopy. The main difference between the two methods is that CD, instead of measuring the absorbance of light as a function of wavelength, measures the difference in absorbance of left versus right circularly polarized light as a function of wavelength. A CD spectrum is an observation of the structure of a chiral compound; it often serves as a “fingerprint” of the structure of biological molecules such as proteins and nucleic acids. For this reason, CD has been broadly applied in biochemistry and …