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Full-Text Articles in Analytical Chemistry

Quantitative Analysis Of Blue 1 Dye In Commercial Sports Drinks By Uv -Vis Spectroscopy And Hplc-Dad, Mikayla Bush Sep 2026

Quantitative Analysis Of Blue 1 Dye In Commercial Sports Drinks By Uv -Vis Spectroscopy And Hplc-Dad, Mikayla Bush

Forensic Science Master's Projects

Food dyes are natural or synthetic substances added to foods, beverages, and cosmetics to enhance color and visual appeal. Although they provide no nutritional value, they are widely used to attract consumers, particularly children. Concerns have been raised about the potential health effects of synthetic dyes, including links to hyperactivity in children, tumor formation at high doses, and possible impacts on gut and brain function. In response, regulatory efforts are ongoing. In April 2025, the U.S. Department of Health and Human Services (HHS) and the Food and Drug Administration (FDA) announced an initiative to phase out petroleum-based food dyes, including …


Development Of Ultrafast Protein Digestion And Standards Free Quantitation Methods For Mass Spectrometric Analysis, Praneeth Ivan Joel Fnu Aug 2026

Development Of Ultrafast Protein Digestion And Standards Free Quantitation Methods For Mass Spectrometric Analysis, Praneeth Ivan Joel Fnu

Dissertations

A wide variety of biologically important molecules, such as enzymes, antibodies, hormones, transporters and receptors are proteins by composition and they play key roles in biological functions such as cellular regulation, communication, metabolism and physiological function. Protein dysfunctions and abnormalities are associated with numerous diseases, making proteins critical targets for understanding disease mechanisms and developing therapeutic interventions. Protein-based therapeutics such as monoclonal antibodies, hormones and vaccines gained popularity due to their high specificity, efficacy, and ability to treat complex diseases that are often difficult to address with small-molecule drugs.

Given the important role of proteins in a variety of biological …


Electrolyte Development And Interfacial Reactions At Multivalent Metal Anode For Next Generation Energy Storage Systems, Leslie Gates Aug 2026

Electrolyte Development And Interfacial Reactions At Multivalent Metal Anode For Next Generation Energy Storage Systems, Leslie Gates

Graduate Masters Theses

The increasing demand for safe, sustainable, and high-performance energy storage systems has driven significant interest in multivalent-ion batteries, including aluminum, magnesium, and zinc-based systems. These technologies have attracted attention due to their high theoretical energy densities, natural abundance, low cost, and environmentally benign nature. However, their development remains hindered by a limited fundamental understanding of electrolyte development and interfacial processes at the electrode–electrolyte interface, where complex electrochemical interactions govern battery performance and stability.

This thesis investigates electrode–electrolyte interactions in both a novel aluminum electrolyte and divalent magnesium and zinc systems. Beginning with the development and characterization of a novel aluminum …


Effects Of Bidisperse Gold Nanoparticles On Near-Infrared Surface-Enhanced Raman Spectroscopy (Sers) In Quick-Freezing-Induced Gold Nanoparticle Aggregates (Qfiaas), Elissa M. Dojka Aug 2026

Effects Of Bidisperse Gold Nanoparticles On Near-Infrared Surface-Enhanced Raman Spectroscopy (Sers) In Quick-Freezing-Induced Gold Nanoparticle Aggregates (Qfiaas), Elissa M. Dojka

Forensic Science Master's Projects

Gold nanoparticle (AuNP) aggregates formed via rapid freezing in liquid nitrogen exhibit strong near-infrared (NIR) plasmonic coupling. These quick-freezing-induced AuNP aggregates (QFIAAs) form moderately sized, colloidally stable structures that remain suspended for over three months, supporting a variety of analytical applications. Mechanistically, QFIAA formation arises from the confinement of nanoparticles and ions within advancing ice grain boundaries during freeze-concentration. This mechanical crowding promotes extreme physical proximity while simultaneously elevating local ionic strength, which screens electrostatic barriers to drive the assembly of dense, tightly coupled plasmonic networks.

This study investigates the plasmonic and surface-enhanced Raman scattering (SERS) behavior of bidisperse QFIAA …


Analysis Of Terpenes In Cannabis Flowers Using Gas Chromatography Via Headspace-Solid Phase Microextraction (Hs-Spme), Hannah I. Bergner Aug 2026

Analysis Of Terpenes In Cannabis Flowers Using Gas Chromatography Via Headspace-Solid Phase Microextraction (Hs-Spme), Hannah I. Bergner

Forensic Science Master's Projects

As cannabis commercialization grows, rigorous profiling of cannabinoids, terpenes, and chemical contaminants is legally required for industry standardization and consumer safety. Terpenes are highly volatile components that dictate the unique aromatic profiles and therapeutic properties of cannabis via receptor pathways. This project focused on a gas chromatography-flame ionization detector/mass selective detector (GC-FID/MSD) combined with headspace-solid phase microextraction (HS-SPME) sampling to analyze terpenes present in four cannabis samples. Cannabis samples were tightly sealed in vials (10 mL) and heated to vaporize terpenes in the headspace above the samples, followed by the extraction of the vaporized terpenes using a polydimethylsiloxane (PDMS)-coated SPME …


On The Operation Of A Proteomics Core Facility: Selected Mass Spectrometric Studies And Methods, Rachel E. Muriph Aug 2026

On The Operation Of A Proteomics Core Facility: Selected Mass Spectrometric Studies And Methods, Rachel E. Muriph

Graduate Doctoral Dissertations

Mass spectrometry has become an indispensable analytical platform for investigating complex biological systems owing to its sensitivity, selectivity, and molecular specificity. This Dissertation demonstrates the versatility of liquid chromatography-tandem mass spectrometry (LC-MS/MS) through three studies focused on nanoparticle characterization, protein structural analysis, and plasma proteomics. In Chapter 2, LC-MS methods were developed to characterize novel lipidoid incorporated into lipid nanoparticles (LNPs) and to evaluate their in vivo biodistribution following systematic administration. Comparative proteomic analysis of the resulting protein coronas revealed distinct differences between liver and lung targeting LNP formulations, providing insight into the potential role of adsorbed blood proteins in …


The Study Of Hydrophobic Biomolecules With Matrix Assisted Laser Desorption Ionization Mass Spectrometry And Atomic Force Microscopy, Brandy L. Perkins Jul 2026

The Study Of Hydrophobic Biomolecules With Matrix Assisted Laser Desorption Ionization Mass Spectrometry And Atomic Force Microscopy, Brandy L. Perkins

LSU Doctoral Dissertations

Abstract

Matrix assisted laser desorption ionization (MALDI) mass spectrometry (MS) can be used to obtain localization and chemical information of hydrophobic biomolecules on tissue samples.  A technique has been developed to modify a standard MALDI matrix that improves the selectivity for hydrophobic biomolecules on the tissue sample. The modification involves the use of a Group of Uniform Materials Based on Organic Salts (GUMBOS). GUMBOS are ionic liquids (IL) that are bulky organic ions with a counter ion that can be changed for tuning.  They are more stable than traditional matrices under vacuum.  Unlike traditional IL’s, the GUMBOS melting point ranges …


Information Theory Analysis Of Water Vapor Stable Isotopes From The Sail Campaign, Matthew John Rybecky Jul 2026

Information Theory Analysis Of Water Vapor Stable Isotopes From The Sail Campaign, Matthew John Rybecky

Earth and Planetary Sciences ETDs

Understanding the processes that control water vapor isotopic composition in mountain environ- ments is essential for interpreting isotope records and predicting water resource responses to cli- mate change. This thesis applies information theory to continuous, high-resolution water vapor stable isotope measurements from the Surface Atmosphere Integrated Field Laboratory (SAIL) campaign in the East River watershed of Colorado’s Upper Gunnison Basin, spanning the winter- to-spring transition of 2022–2023. The analysis employs Shannon entropy, mutual information, transfer entropy, and joint transfer en- tropy (JTE) to quantify how environmental variables, including surface meteorology, radiation, tur- bulent fluxes, and ERA5 reanalysis products, transfer information …


The Comparative Chemical Analysis Of Colored Henna, Vani D. Bhagwandeen Jun 2026

The Comparative Chemical Analysis Of Colored Henna, Vani D. Bhagwandeen

Student Theses

Henna, a natural dye derived from Lawsonia inermis, is widely used for temporary body art, hair coloring, and cultural decorative practices such as Mehendi. Traditional henna produces a reddish-brown stain through lawsone, a naphthoquinone chromophore that binds to keratin in skin, hair, and nails (Badoni Semwal et al., 2014; de Groot, 2013; Kumar Singh et al., 2015). Commercial henna products have increasingly incorporated synthetic dyes, pigments, and glitter additives to produce a broader range of colors and effects (Blair et al., 2004; Manso et al., 2017; Blackledge & Jones, 2007). Despite their prevalence, limited forensic research has examined the …


Supramolecular Assembly In Short Peptide Systems For Selective Metabolite Recognition And Drug Nanoencapsulation, Maithreyi Ramakrishnan Jun 2026

Supramolecular Assembly In Short Peptide Systems For Selective Metabolite Recognition And Drug Nanoencapsulation, Maithreyi Ramakrishnan

Dissertations, Theses, and Capstone Projects

Short peptides can form adaptive supramolecular assemblies, and understanding how minimal sequences organize around neurometabolites or hydrophobic cancer drugs enables the rational design of functional materials. This thesis combines molecular dynamics with experimental validation to establish design rules linking peptide sequence to emergent structure and function. Chapter 1 outlines the molecular determinants governing peptide assembly. Chapter 2 reviews computational workflows that reveal sequence-dependent conformations and supramolecular organization. Chapter 3 applies these principles to Dynamic Peptide Libraries which identify tetrapeptides that selectively interact with neurometabolites. Chapter 4 extends the same interaction-driven framework to design tryptophan-rich pentapeptides that co-assemble with kinase inhibitors …


The Influence Of Fermentation Duration And Secondary Fermentation Conditions On The Bioactive Compound Profile Of Kombucha, Jordan Vereen May 2026

The Influence Of Fermentation Duration And Secondary Fermentation Conditions On The Bioactive Compound Profile Of Kombucha, Jordan Vereen

Honors Theses

Kombucha is a fermented sweet tea produced using a symbiotic culture of bacteria and yeast (SCOBY) and has gained widespread popularity due to its proposed health benefits. Kombucha has been studied to understand these advantages in cardiovascular support, improved metabolism, increased antioxidant effects, enhanced antimicrobial properties, and even potentially slowing the progression of certain diseases. Despite its increasing popularity, the way in which the specific bioactive compounds responsible for these effects and the fermentation conditions that influence their production remain unclear. The present study, conducted in collaboration with Dr. Budner, focuses on quantifying bioactive compounds in kombucha to better understand …


High Throughput Phenomics Pipeline For Pulse Crop Nutritional Breeding, Amod Udayanga Madurapperumage May 2026

High Throughput Phenomics Pipeline For Pulse Crop Nutritional Breeding, Amod Udayanga Madurapperumage

All Dissertations

Dry pea (Pisum sativum L.), lentil (Lens culinaris Medik.), and chickpea (Cicer arietinum L.) are major pulse crops valued for their high nutritional composition and importance to global food systems. Pulses are rich in carbohydrates, protein, and essential minerals, making them ideal whole foods and critical contributors to food and nutrition security. Due to these advantages, pulse breeding programs are increasingly focusing on enhancing nutritional traits, such as protein quality, amino acid balance, and micronutrient density, through the process of biofortification. However, improvement of agronomic traits remains equally essential. Characteristics such as plant height, standability, stress tolerance, …


Urea-Based Boronium Salts As Antimicrobial Agents, Gabriel Allen Merchant May 2026

Urea-Based Boronium Salts As Antimicrobial Agents, Gabriel Allen Merchant

Honors Theses

Quaternary ammonium compounds (QACs) are widely used in disinfectants due to their ability to inhibit the growth of and eliminate microbes. The potency, broad-spectrum activity, and low cost of QACs have made them a cornerstone of modem hygiene. In recent years, QACs have garnered many health and safety concerns due to their overuse and subsequent accumulation in the environment. The increased use of QACs has further led to an increase in antimicrobial-resistant bacteria, making the synthesis of novel antibacterial compounds vital to combat this growing threat. Recent advances in boronium salts offer a unique alternative to address these adverse effects. …


Stability Of Paraffin-Insulated Nitrogen-Doped Carbon Fiber Ultramicroelectrodes, Maxwell H. Kwakwah May 2026

Stability Of Paraffin-Insulated Nitrogen-Doped Carbon Fiber Ultramicroelectrodes, Maxwell H. Kwakwah

Electronic Theses and Dissertations

Nitrogen-doped carbon materials can facilitate the reduction oxygen-oxygen bonds, a key step in electroreduction of both O2 (an important reaction in energy applications) and H₂O₂ (an important reaction in sensing and biosensing). Our lab previously demonstrated that thermal decomposition of urea in the presence of carbon fiber (CF) results in an N-doped carbon material that exhibits good electrocatalytic properties for H₂O₂ reduction. However, previous methods of insulating single N-doped CF via laser heating of borosilicate capillaries and epoxy to prepare ultramicroelectrodes (UMEs) seemed to adversely affect surface nitrogen contents and electrocatalytic properties. More recent work that utilized paraffin to …


Taking A Deeper Look: Attributing Tonal Values Of Photolumens To Their Emulsions Using Scanning Electron Microscopy, Anna M. Moore May 2026

Taking A Deeper Look: Attributing Tonal Values Of Photolumens To Their Emulsions Using Scanning Electron Microscopy, Anna M. Moore

All Theses

This thesis examines whether tonal variation in photolumens made with historic silver gelatin photographic papers can be linked to differences in elemental composition. Photolumens are cameraless photographic images created by placing objects directly on light-sensitive paper and exposing them to ultraviolet light. Because expired and historic darkroom papers often produce unpredictable colors and tones, this study asks whether visually defined tonal groups also show measurable chemical differences.

Twenty historic paper samples were exposed, documented, and sorted into five tonal groups based on visible image characteristics. Each sample was then analyzed using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) …


Energetic Eutectics: An Experimental And Computational Investigation On Explosive Deep Eutectic Solvents, Connor J. Parker May 2026

Energetic Eutectics: An Experimental And Computational Investigation On Explosive Deep Eutectic Solvents, Connor J. Parker

All Theses

This study reports on the incorporation an extreme gradient boosting (XGBoost) machine learning strategy tailored to identifying potential high-energy, insensitive explosive deep eutectic solvents. 1,1-diamino-2,2-dinitroethylene (FOX-7) was investigated as the explosive of interest in our eutectic modeling. The resulting predictions highlighted a wide range of binary compositions demonstrating significant depression from the FOX-7 melting temperature with >70% probabilities of formation. Subsequent computational investigation into select mixtures provided underlying stabilization energies and optimized mixture geometries, which were then assessed experimentally with near simulant compounds oxalyldihydrazide and 1-methyl-3- nitroguanidine replacing FOX-7.

Experimental results with these chosen simulants did not demonstrate classical eutectic …


Degradation And Metabolic Analysis Of Synthesized Quorum-Sensing Signals By The Model Eukaryote Chlamydomonas Reinhardtii, Adam Josef Bach May 2026

Degradation And Metabolic Analysis Of Synthesized Quorum-Sensing Signals By The Model Eukaryote Chlamydomonas Reinhardtii, Adam Josef Bach

Theses and Dissertations

Bacterial organisms can “talk” with one another on a colony-wide scale using a communication system known as quorum-sensing (QS) via chemical signals. These signals are produced at a basal rate throughout the life of the bacteria and are classified as autoinducers, which diffuse across the cell membrane. Once the critical concentration is reached, they begin to diffuse back into the cell and initiate a phenotypic change. As these signals exist outside the membrane of their producer, they are also accessible to other organisms. It has already been noted that some plant species uptake these compounds through their roots and break …


Advancement In Electrochemical Generation-Collection: Snapshot Redox Cycling Voltammetry For Rapid Analysis At Chip-Based, Individually Addressable Microband Electrode Arrays, Blake Aleck Sterling May 2026

Advancement In Electrochemical Generation-Collection: Snapshot Redox Cycling Voltammetry For Rapid Analysis At Chip-Based, Individually Addressable Microband Electrode Arrays, Blake Aleck Sterling

Graduate Theses and Dissertations

Snapshot redox cycling voltammetry (Snapshot RCV) is introduced as a rapid electrochemical technique that reconstructs the current-potential profile of a redox active species using a microband electrode array. By simultaneously biasing individual generator electrodes alternating in the array to different voltages across the analyte’s potential range while individually holding collector electrodes at a reversing potential, “spatial” voltammetry is achieved in as little as 1 s with the temporal speed of chronoamperometry, rapidly capturing the steady-state redox cycling (RC) profiles. During RC (a mode of generation-collection), the analyte is oxidized (or reduced) at generator electrodes and converted back at neighboring collector …


Investigation Of Curing And Degradation Mechanisms In Lead White Oil Paint Systems: Impact Of Methyl Linoleate On Paint Matrix Formation And Solvent Extractability, Andrea Serrano Trujillo May 2026

Investigation Of Curing And Degradation Mechanisms In Lead White Oil Paint Systems: Impact Of Methyl Linoleate On Paint Matrix Formation And Solvent Extractability, Andrea Serrano Trujillo

Theses, Dissertations and Culminating Projects

Oil-based paints composed of drying oils and lead-containing pigments undergo complex chemical transformations during curing that influence long-term stability and degradation. Despite centuries of use, the molecular mechanisms governing oxidative polymerization and additive incorporation in lead white oil paint systems remain incompletely understood. This study investigates the role of methyl linoleate, a monoester analog of linoleic acid, in the curing and degradation pathways of lead carbonate and linseed oil paint films. A deep focus was placed on determining whether methyl linoleate becomes chemically integrated into the developing polymeric network or remains as an extractable and unbound component, as this distinction …


Nanoscale Electrochemical Measurements: Theory, Instrumentation, And Operation, Kamsy Lerae Anderson May 2026

Nanoscale Electrochemical Measurements: Theory, Instrumentation, And Operation, Kamsy Lerae Anderson

Graduate Theses and Dissertations

Electrochemical processes underpin many modern technologies (e.g., batteries, fuel cells, and corrosion protection systems), and because these processes are often controlled by interactions that occur at the nanoscale, gaining insight into nanoscale electrochemical behavior is essential to advancing these technologies. Nanoscale electrochemical imaging probes measure electrochemical activity with nanoscale spatial resolution and have enabled researchers to gain new insights into diverse experimental systems. However, limitations remain, including a lack of methods for direct quantitative interpretation, the influence of atmospheric conditions on experimental reproducibility and stability, and a knowledge barrier resulting from limited accessible resources, all of which continue to restrict …


Analysis Of The Flavonoid Composition Of Honey Using High-Performance Liquid Chromatography, Bryce Phillips Apr 2026

Analysis Of The Flavonoid Composition Of Honey Using High-Performance Liquid Chromatography, Bryce Phillips

Honors Theses

Honey is a naturally occurring substance that has a complex composition including compounds such as flavonoids, that contribute to potential health benefits. Quantitative analysis of flavonoids in honey can be challenging due to their similar structural characteristics, matrix effects, and chromatographic peak separation issues. This study aimed to establish calibration curves for five flavonoids–kaempferol, luteolin, chrysin, myricetin, and quercetin– to estimate their concentrations in five honey samples from varying geographic origins. Liquid-liquid extraction was used to isolate the flavonoids from honey. High Performance Liquid Chromatography was utilized to establish calibration curves and analyze honey samples. The calibration curves assembled demonstrated …


Designing Surface-Induced Entatic States In Copper Complexes For Tunable Reactivity, Rachel Kiser Apr 2026

Designing Surface-Induced Entatic States In Copper Complexes For Tunable Reactivity, Rachel Kiser

Senior Theses

Copper catalysts play an important role in electrocatalytic oxidation reactions due to their redox flexibility and relative abundance compared to noble metal catalysts. In biological systems, copper metalloenzymes often achieve enhanced reactivity through an entatic state. Entasis is described as an active site or metal center being constrained to a geometric and electronic state, minimizing primary sphere reorganization energy and achieving higher rates of electron transfer.  This study investigates whether entasis can be achieved in synthetic molecular catalysts by immobilizing Cu(I) complexes onto metal oxide surfaces. Two Cu(I) complexes bearing carboxylate-functionalized ligands were examined both in homogeneous solution and when …


Radicals Transforming Organic Matter: Implications For Non-Pyrogenic Black Carbon And Nitrogen Formation, Molecular Dynamics In Tropical Soils, And Lignin Valorization, João Vitor Dos Santos Apr 2026

Radicals Transforming Organic Matter: Implications For Non-Pyrogenic Black Carbon And Nitrogen Formation, Molecular Dynamics In Tropical Soils, And Lignin Valorization, João Vitor Dos Santos

Chemistry & Biochemistry Theses & Dissertations

Radicals drive the transformation of organic matter in natural and engineered systems, altering its structure, reactivity, and stability. Condensed aromatic carbon (ConAC) and condensed aromatic nitrogen (ConAN) are among the most persistent forms of organic matter in soils and are traditionally interpreted as products of biomass burning. This dissertation challenges the long-standing assumption that these materials are exclusively pyrogenic, showing that iron-mediated radical chemistry can generate condensed aromatic structures under ambient conditions.

Chapters II and III show that Fenton-like radical oxidation of lignin-rich biomass produces condensed aromatic structures compositionally similar to pyrogenic black carbon and black nitrogen when assessed with …


Monosaccharide Binding To Synthetic Carbohydrate Receptor Microarrays, Milan A. Shlain Feb 2026

Monosaccharide Binding To Synthetic Carbohydrate Receptor Microarrays, Milan A. Shlain

Dissertations, Theses, and Capstone Projects

Chapter 1: A glycan detection platform comprised of synthetic carbohydrate receptors (SCRs) immobilized onto polymer brushes was prepared. SCR043, an alkene-containing SCR, was incorporated into grafted-from polymer brushes using hypersurface photolithography, resulting in microarrays of SCR043-functionalized polymer brushes, where brush height (h) and SCR grafting density (Γ) is controlled precisely at each feature in the array. The influence of h and Γ on the binding to five fluorescently labelled monosaccharides – α-glucose (α-Gluc-FL), α-galactose (α-Gal-FL), α-mannose (α-Man-FL), β-glucose (β-Gluc-FL), and β-galactose (β-Gal-FL) – in aqueous buffer …


The Behavior And Complexation Of Technetium Under Conditions Relevant For Nuclear Fuel Reprocessing, Rachel E. Greenberg Feb 2026

The Behavior And Complexation Of Technetium Under Conditions Relevant For Nuclear Fuel Reprocessing, Rachel E. Greenberg

Dissertations, Theses, and Capstone Projects

Spent nuclear fuel is reprocessed by utilizing several large-scale solvent extraction processes. One of the most prevalent of these processes is the plutonium uranium reduction extraction (PUREX) process. This process involves an organic phase composed of tributyl phosphate (TBP) in kerosene and an aqueous phase comprised of concentrated nitric acid. Both uranium (U) and plutonium (Pu) are extracted into the organic phase by nitrate and TBP complexation while the various fission products remain in the initial aqueous phase. Pu is then chemically reduced to its trivalent state and back-extracted into a second aqueous phase, thereby separating the two fissile materials. …


Design Of Lithium-Based Battery Electrolyte Compositions For Extreme Operating Conditions Using Alternative Solvents, Co-Solvents And Additives, Michael J. Keating Feb 2026

Design Of Lithium-Based Battery Electrolyte Compositions For Extreme Operating Conditions Using Alternative Solvents, Co-Solvents And Additives, Michael J. Keating

Dissertations, Theses, and Capstone Projects

Lithium-ion battery utilization is widespread due to relatively high capacity and long cycle life. Advanced technologies have specific demands of their energy storage devices that traditional Li-ion batteries are unable to meet. Lithium-ion batteries utilize a graphite anode which has a limited theoretical capacity. Traditional lithium-ion batteries also utilize flammable solvents in their electrolyte mixtures. Due to the flammable electrolyte, lithium-ion batteries are not considered practical for large scale applications. Additionally, the lithium-ion battery has a narrow optimal operating temperature window. The temperature limitation of lithium-ion batteries leads to issues for many applications such as operating in extreme temperature environments, …


Development And Validation Of An Analytical Method For Quantitative Determination Of Small Aldehydes In Plasma, Stephanie T. Clark Jan 2026

Development And Validation Of An Analytical Method For Quantitative Determination Of Small Aldehydes In Plasma, Stephanie T. Clark

Chemistry & Biochemistry Theses - Archive

Small aldehydes such as formaldehyde and acetaldehyde are highly reactive metabolites that play important roles in biological processes related to oxidative stress, metabolism, and DNA damage. Because of their chemical reactivity, volatility, and low endogenous concentrations, accurate measurement of these compounds in biological samples remains analytically challenging. The goal was to develop and evaluate a practical analytical method for detecting small aldehydes in biologically relevant matrices using headspace gas chromatography mass spectrometry (HS-GC-MS). The method combined chemical derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) and headspace sampling to stabilize aldehydes and enable selective detection by mass spectrometry. Method development focused on optimizing derivatization …


Advancing Lipidomics Through Fluoroalcohol-Induced Multiphase Fractionation And Orthogonal Lc×Lc–Ms Detection, Md Al Amin Jan 2026

Advancing Lipidomics Through Fluoroalcohol-Induced Multiphase Fractionation And Orthogonal Lc×Lc–Ms Detection, Md Al Amin

Chemistry & Biochemistry Dissertations

Comprehensive characterization of the lipidome remains a significant analytical challenge due to the immense structural diversity, wide dynamic range, and complex physicochemical continuum of lipid species. Conventional extraction methods, such as those by Bligh–Dyer and Folch, and one-dimensional liquid chromatography (1D-LC) often fail to resolve this complexity, leading to chromatographic overlap, severe ion suppression, and limited coverage of low-abundance or highly hydrophobic species. This dissertation addresses these bottlenecks by establishing a separation-driven analytical framework that integrates novel fluoroalcohol-induced multiphase systems (FAiTPS) with orthogonal multidimensional liquid chromatography–mass spectrometry (LC×LC–MS).

The core of this research is the development and physicochemical characterization of …


Flow Injection Determination Of Fluoride For Total Organic Fluorine Analysis, Memona Zulafiqar Jan 2026

Flow Injection Determination Of Fluoride For Total Organic Fluorine Analysis, Memona Zulafiqar

Chemistry & Biochemistry Theses

Poly- and perfluoroalkyl substances (PFAS) are anthropogenic chemicals that have gained increasing attention due to their association with a wide range of adverse health effects. These compounds are highly diverse, with approximately 15,000 PFAS reported. Their exceptional environmental stability and strong tendency to bioaccumulate result in environmentally relevant concentrations that typically occur at very low levels, often in the ng L⁻¹ range. This chemical diversity presents a major analytical challenge, as reference standards are available for only a limited number of PFAS. Consequently, conventional targeted analytical methods frequently quantify less than 1% of the total PFAS present, leading to a …


Identification Of Modified Polymer End Groups For Correlations To Physical Properties, Tj Sacco Jan 2026

Identification Of Modified Polymer End Groups For Correlations To Physical Properties, Tj Sacco

Williams Honors College, Honors Research Projects

Plastic has become the primary material for containers in both industrial and commercial fields. Plastics are the optimal choice since they have many physical properties that make them ideal candidates: durability, heat resistance, chemical stability, as well as their inexpensive production cost. Nowadays, the desire for more versatile plastics with strength, flexibility, hydrophobicity, and biodegradability has grown; however, concerns for plastic use have started to rise as well. The overuse of plastics poses a threat to the environment and people’s health: plastics are hard to break down completely which results in the formation of micro(nano)plastics (MNPs). In attempts to circumvent …