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Full-Text Articles in Physical Sciences and Mathematics

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 Dec 2022

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 Feb 2022

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 …


Elemental Composition And Arsenic Speciation Analysis Of Processed Seafood Products Using Atomic Spectrometric Techniques, Austin A. Roberts Jan 2020

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 Jun 2019

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 Mar 2019

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 Jan 2019

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 Aug 2018

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 Jul 2018

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 Apr 2018

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 Mar 2018

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 …


Development Of Bioanalytical Methods For Quantitative Measurement Of Anticancer Agents, Sandeep R. Kunati Jan 2018

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 Jan 2018

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 …


Qualitative Analysis For The Characterization And Discrimination Of Printing Inks, Rhett J. Williamson Oct 2016

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 …


Development Of A Primary Ion Column For Mass Spectrometry-Based Surface Analysis, Raul A. Villacob Jul 2016

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 May 2016

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 Jan 2016

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 Jan 2016

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 Jan 2016

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 Jan 2016

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 …


Determination Of Extracellular Molecules Produced By Vibrio Harveyi Using Ms/Ms, Jose G. Roble Jul 2015

Determination Of Extracellular Molecules Produced By Vibrio Harveyi Using Ms/Ms, Jose G. Roble

FIU Electronic Theses and Dissertations

Quorum sensing (QS) is a process that allows bacteria to sense the population density of cells around them by communicating with each other via autoinducer molecules. This cross-communication is crucial in the regulation of bacterial processes such as bioluminescence, virulence, and biofilm formation. Previous research by Milburn and Makemson on Vibrio harveyi suggested that in addition of the known biosynthesis of three well-characterized autoinducers, dozens of unknown molecules are also produced and released to the environment by V. harveyi. This study was performed using electrospray tandem mass spectrometry with the purpose of detection and characterization of the extracellular molecules …


Mass Spectrometric Characterization And Imaging Of Nanoparticles In Biological Samples, Bo Yan Aug 2014

Mass Spectrometric Characterization And Imaging Of Nanoparticles In Biological Samples, Bo Yan

Doctoral Dissertations

Nanoparticles (NPs) are being investigated widely for use in biomedical applications such as imaging, drug delivery, and cancer therapy due to their small size and readily tunable properties. The ability to accurately characterize NPs and monitor their spatial distributions is highly desirable for effective use of NPs and evaluation of their potential adverse environmental, health, and safety effects. In this dissertation, a simple, fast, and sensitive method based on laser desorption/ionization mass spectrometry (LDI-MS) to characterize and track NPs in biological systems has been developed. This method is especially well suited for characterizing core-shell structured NPs, such as quantum dots …


Complementary Spectroscopic Assays For Investigating Protein−Ligand Binding Activity: A Project For The Advanced Chemistry Laboratory, David Mascotti, Mark Waner May 2013

Complementary Spectroscopic Assays For Investigating Protein−Ligand Binding Activity: A Project For The Advanced Chemistry Laboratory, David Mascotti, Mark Waner

Mark J. Waner

A protein−ligand binding, guided-inquiry laboratory project with potential application across the advanced undergraduate curriculum is described. At the heart of the project are fluorescence and spectrophotometric assays utilizing biotin-4-fluorescein and streptavidin. The use of the same stock solutions for an assay that may be examined by two distinct spectroscopic techniques offers an opportunity to discuss not only protein−ligand binding but also to compare instrumental techniques and to discuss the underlying physical principles that are the origins of the assays. In addition to critically evaluating analytical techniques, students are pushed to develop quantitative pipetting, estimation, and experimental-design skills to collect and …


Chemical Analysis Of Ophthalmic Solutions, Pagagiotis Tavlarakis Jan 2013

Chemical Analysis Of Ophthalmic Solutions, Pagagiotis Tavlarakis

Seton Hall University Dissertations and Theses (ETDs)

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Laboratory Methods For The Advancement Of Wastewater Treatment Modeling, Holly E. Gray Jan 2012

Laboratory Methods For The Advancement Of Wastewater Treatment Modeling, Holly E. Gray

Theses and Dissertations (Comprehensive)

To achieve the low levels of total phosphorus required in wastewater treatment plant effluent all chemical forms of phosphorus should be removed. The most refractory phosphorus in terms of removal is so-called “organic phosphorus”. This thesis explores potential relationships between dissolved organic matter and organic phosphorus and methods of removing organic phosphorus from waste water. Fluorescence spectroscopy will be used to characterize dissolved organic matter (DOM) in wastewater. The fluorescent DOM will then be monitored throughout the various wastewater treatment plants to investigate any changes throughout the treatment train. Correlations between fluorophore concentrations (concentrations determined for the different classifications of …


Complementary Spectroscopic Assays For Investigating Protein−Ligand Binding Activity: A Project For The Advanced Chemistry Laboratory, David Mascotti, Mark Waner Jun 2010

Complementary Spectroscopic Assays For Investigating Protein−Ligand Binding Activity: A Project For The Advanced Chemistry Laboratory, David Mascotti, Mark Waner

David P. Mascotti

A protein−ligand binding, guided-inquiry laboratory project with potential application across the advanced undergraduate curriculum is described. At the heart of the project are fluorescence and spectrophotometric assays utilizing biotin-4-fluorescein and streptavidin. The use of the same stock solutions for an assay that may be examined by two distinct spectroscopic techniques offers an opportunity to discuss not only protein−ligand binding but also to compare instrumental techniques and to discuss the underlying physical principles that are the origins of the assays. In addition to critically evaluating analytical techniques, students are pushed to develop quantitative pipetting, estimation, and experimental-design skills to collect and …


Analytical Chemistry 2.0, David Harvey Jan 2010

Analytical Chemistry 2.0, David Harvey

Chemistry & Biochemistry Faculty Publications

No abstract provided.


Comparison Of The Maximum Sensitivity Of Different Flow Injection Manifold Configurations: Alternating Variable Search Optimization Of The Iron(Ii)/1,10-Phenanthroline System, Sj Chalk, Julian Tyson Jan 1994

Comparison Of The Maximum Sensitivity Of Different Flow Injection Manifold Configurations: Alternating Variable Search Optimization Of The Iron(Ii)/1,10-Phenanthroline System, Sj Chalk, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.


An Experiment Using Time-Based Detection In Flow Injection Analysis, Mary K. Carroll, Julian Tyson Jan 1993

An Experiment Using Time-Based Detection In Flow Injection Analysis, Mary K. Carroll, Julian Tyson

Chemistry Department Faculty Publication Series

We present a laboratory experiment, suitable for implementation in analytical chemistry courses at the undergraduate level, that demonstrates the utility of time-based measurements with doublet peaks in flow injection analysis. The measurements are taken with an instrument that incorporates a simple solid-state detector, which has as its source a light-emitting diode (LED) and as its detecting element a photodiode (PD). The system studied here is a simple acid-base titration. The experiment could be adapted to any number of chemical reactions that result in a product that absorbs light of the LED wavelength significantly.


Putting The Chemistry Back Into Analytical Chemistry, Julian Tyson Jan 1992

Putting The Chemistry Back Into Analytical Chemistry, Julian Tyson

Chemistry Department Faculty Publication Series

Aspects of the current status of and research in analytical chemistry are briefly discussed and the need for cost effective analytical procedures is emphasized. The present and future of a number of aspects of flow-injection analysis are considered. These include the basic theory, the kinetic features, the control features, time-based methodology, and the coupling of sample pretreatment with instrumentation. Several aspects of this latter topic are con­sidered with particular reference to the flow-injection atomic spectrometry combination. Problems of kinetic mismatch between chemistry, manifold residence, and instrument op­eration are discussed and some possible solutions proposed including the use of closed loop …


Study Of The Hexamethylenetetramine, Ammonia, And Formaldehyde System: Quantitative Determinations, Gary Lee Madsen Jan 1992

Study Of The Hexamethylenetetramine, Ammonia, And Formaldehyde System: Quantitative Determinations, Gary Lee Madsen

Dissertations

No abstract provided.