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2025

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Articles 61 - 90 of 122

Full-Text Articles in Analytical Chemistry

Silver Nanoparticles In Ammonia Sensing And Photovoltaics, Madhuka Liyanage May 2025

Silver Nanoparticles In Ammonia Sensing And Photovoltaics, Madhuka Liyanage

All Dissertations

Nanocomposite films (NCF) containing silver nanoparticles (AgNPs), separated by thin layers of silica/poly-4-vinylpyridine/polyvinylpyrrolidone, were fabricated via drop casting, spin coating, dip coating on glass substrate and drop casting on nylon filter membranes. The more uniform films were produced by drop casting on nylon filter membranes due to their solvent wicking properties. The films demonstrate electrical conductivity that varies in response to moist ammonia and water vapors. The changes in conductivity are attributed to hydrogen bonding between ammonia and water molecules with the silica/polymer layers, as well as the direct adsorption of ammonia onto the silver surface. Notably, NCFs with polyvinylpyrrolidone …


Qualitative And Quantitative Analysis Of New Psychoactive Substances And Related Metabolites Using Liquid Chromatography-Ion Mobility-Mass Spectrometry (Lc-Im-Ms), Ralph Aderorho May 2025

Qualitative And Quantitative Analysis Of New Psychoactive Substances And Related Metabolites Using Liquid Chromatography-Ion Mobility-Mass Spectrometry (Lc-Im-Ms), Ralph Aderorho

All Dissertations

The increasing prevalence of novel psychoactive substances (NPS) in illicit drug markets has posed significant challenges for forensic and clinical toxicology, primarily due to the structural similarity and diversity among these compounds. This dissertation investigates the application of advanced liquid chromatography-ion mobility-mass spectrometry (LC-IM-MS/MS) techniques, using the high-resolution Structures for Lossless Ion Manipulations (SLIM) platform and the drift tube ion mobility spectrometry (DT-IMS), for the qualitative and quantitative analysis of various types of synthetic opioids, synthetic cannabinoids, psychedelics and xylazine. By combining IMS separations with mass spectrometry and targeted chemical derivatization, this work enhances the ability to distinguish and characterize …


The Design And Optimization Of Optical Systems For The Detection And Characterization Of Phytoplankton, Caitlyn M. English Apr 2025

The Design And Optimization Of Optical Systems For The Detection And Characterization Of Phytoplankton, Caitlyn M. English

Theses and Dissertations

Phytoplankton are among the smallest organisms found in marine and freshwater ecosystems. Despite their small size, phytoplankton play a vital role in sustaining life on Earth as primary producers. Through oxygenic photosynthesis phytoplankton are also responsible for large scale carbon fixation and oxygen production. The distribution of phytoplankton in a given water resource can exhibit a high degree of variability across time and space, and this is in large part due to their varying sensitivities to environmental conditions such as resource availability and grazing by predator organisms. As such, phytoplankton community structure is widely used as an investigative tool for …


Hplc Method Development For The Separation And Quantification Of Common Pain Relievers, Dylan Pritchett, Joshua Lewis, Jennifer Firestine Apr 2025

Hplc Method Development For The Separation And Quantification Of Common Pain Relievers, Dylan Pritchett, Joshua Lewis, Jennifer Firestine

2025 Student Academic Showcase

Over-the-counter pain relievers often contain multiple active ingredients that can be analyzed by High Performance Liquid Chromatography (HPLC). A method developed and optimized to separate acetaminophen, aspirin, and caffeine from these tablets. The contents of Excedrin pain relievers and the generic counterpart from Walgreens, Walmart, and CVS were tested. Optimization examined multiple mobile phases, temperatures, and run times for the procedure. The results were compared to analytically prepared standards as well as the packaging information, with the primary goal of creating a reproducible and efficient protocol for HPLC instrumentation. The method successfully separated the contents of all materials reliably within …


Maldi-Mass Spectrometry Imaging To Investigate Distribution Of Per- And Polyfluoroalkyl Substances In Exposed Poplar Tissues, Tonglin Zhou, Varuni Abhayarayne, Joseph Akor, Honglan Shi, Paul Ki-Souk Nam, Joel Gerard Burken, John Yang Apr 2025

Maldi-Mass Spectrometry Imaging To Investigate Distribution Of Per- And Polyfluoroalkyl Substances In Exposed Poplar Tissues, Tonglin Zhou, Varuni Abhayarayne, Joseph Akor, Honglan Shi, Paul Ki-Souk Nam, Joel Gerard Burken, John Yang

Miners Solving for Tomorrow Research Conference

No abstract provided.


Application Of Analytical Methodologies To The Analysis Of Food Flavoring Agents: Part Ii, James Daniel, Kexin Li, Anaaya Monroe, Melissa C. Rhoten Apr 2025

Application Of Analytical Methodologies To The Analysis Of Food Flavoring Agents: Part Ii, James Daniel, Kexin Li, Anaaya Monroe, Melissa C. Rhoten

Spring Showcase for Research and Creative Inquiry

No abstract provided.


Application Of Analytical Methodologies To The Analysis Of Food Flavoring Agents: Part Iii, Samantha Ruano, Bryant Corbin, Moorea Whitfield, Melissa C. Rhoten Apr 2025

Application Of Analytical Methodologies To The Analysis Of Food Flavoring Agents: Part Iii, Samantha Ruano, Bryant Corbin, Moorea Whitfield, Melissa C. Rhoten

Spring Showcase for Research and Creative Inquiry

No abstract provided.


Application Of Analytical Methodologies To The Analysis Of Food Flavoring Agents: Part Iv, Tyler Witt, Anna Wallace, Melissa C. Rhoten Apr 2025

Application Of Analytical Methodologies To The Analysis Of Food Flavoring Agents: Part Iv, Tyler Witt, Anna Wallace, Melissa C. Rhoten

Spring Showcase for Research and Creative Inquiry

No abstract provided.


Study On Dopamine Electrochemical Sensing Based On Au@Mos2, Ning An, Ni Su, Xin-Ran Li, Jian-Yu Liu, Qi-Yan Wang Mar 2025

Study On Dopamine Electrochemical Sensing Based On Au@Mos2, Ning An, Ni Su, Xin-Ran Li, Jian-Yu Liu, Qi-Yan Wang

Journal of Electrochemistry

Dopamine (DA) is a vital neurotransmitter, and accurate detection of its concentration is critical for both clinical diagnostics and neuroscience research. Due to its electrochemical activity, DA is commonly detected using electrochemical methods, which are favored for their simplicity, fast response time, and suitability for in vivo analysis. In this work, a highly sensitive DA electrochemical sensor was developed using an Au@MoS2 composite, created by modifying molybdenum disulfide (MoS2) nanosheets with gold nanoparticles through HAuCl4 reduction, and it was aimed at enhancing DA adsorption and improving detection performance. Scanning Electron Microscopy (SEM), transmission electron microscopy (TEM), …


Recent Advances In Non-Enzymatic Electrochemical Sensors For Theophylline Detection, Gustria Ernis, Yulia M T A Putri, Muhammad Iqbal Syauqi, Prastika Krisma Jiwanti, Yeni Wahyuni Hartati, Takeshi Kondo, Qonita Kurnia Anjani, Jarnuzi Gunlazuardi Mar 2025

Recent Advances In Non-Enzymatic Electrochemical Sensors For Theophylline Detection, Gustria Ernis, Yulia M T A Putri, Muhammad Iqbal Syauqi, Prastika Krisma Jiwanti, Yeni Wahyuni Hartati, Takeshi Kondo, Qonita Kurnia Anjani, Jarnuzi Gunlazuardi

Journal of Electrochemistry

Detection of target analytes at low concentrations is significant in various fields, including pharmaceuticals, healthcare, and environmental protection. Theophylline (TP), a natural alkaloid used as a bronchodilator to treat respiratory disorders such as asthma, bronchitis, and emphysema, has a narrow therapeutic window with a safe plasma concentration ranging from 55.5–111.0 μmol·L–1 in adults. Accurate monitoring of TP levels is essential because too low or too high can cause serious side effects. In this regard, non-enzymatic electrochemical sensors offer a practical solution with rapidity, portability, and high sensitivity. This article aims to provide a comprehensive review of the recent developments …


In-Situ Electrodeposition Of Feco-Mof On Au Ultramicroelectrode For Highly Sensitive Detection Of Epinephrine, Yan Chen, Shang Jian, Si-Yu Wan, Xiao-Tong Cui, Zhong-Gang Liu, Zheng Guo Mar 2025

In-Situ Electrodeposition Of Feco-Mof On Au Ultramicroelectrode For Highly Sensitive Detection Of Epinephrine, Yan Chen, Shang Jian, Si-Yu Wan, Xiao-Tong Cui, Zhong-Gang Liu, Zheng Guo

Journal of Electrochemistry

Metal-organic framework (MOF) nanostructures have emerged as a prominent class of materials in the advancement of electrochemical sensors. The rational design of bimetallic MOF-functionalized microelectrode is of importance for improving the electrochemical performance but still in great challenge. In this work, the bimetallic FeCo-MOF nanostructures were assembled onto a gold disk ultramicroelectrode (Au UME, 5.2 μm in diameter) via an in-situ electrodeposition method, which enhanced the sensitive detection of epinephrine (EP). The in-situ electrodeposited FeCo-MOF exhibited a characteristic nanoflower-like morphology and was uniformly dispersed on the Au UME. The FeCo-MOF/Au UME demonstrated excellent electrochemical performance on the detection of EP …


Per- And Polyfluoroalkyl Substance (Pfas) Degradation In Water And Soil Using Cold Atmospheric Plasma (Cap): A Review, Victor Somtochukwu Mbanugo, Boluwatife Stephen Ojo, Ta Chun Lin, Yue-Wern Huang, Marek Locmelis, Daoru Han Mar 2025

Per- And Polyfluoroalkyl Substance (Pfas) Degradation In Water And Soil Using Cold Atmospheric Plasma (Cap): A Review, Victor Somtochukwu Mbanugo, Boluwatife Stephen Ojo, Ta Chun Lin, Yue-Wern Huang, Marek Locmelis, Daoru Han

Biological Sciences Faculty Research & Creative Works

Per- and polyfluoroalkyl substances (PFASs) are persistent organic chemicals found in numerous industrial applications and everyday products. The excessive amounts of PFASs in water and soil, together with their link to severe health issues, have prompted substantial public concerns, making their removal from the environment a necessity. Existing degradation techniques are frequently lacking due to their low efficiency, cost-effectiveness, and potential for secondary contamination. Cold Atmospheric Plasma (CAP) technology has emerged as a promising alternative, utilizing energized reactive species to break down PFASs under ambient conditions. Therefore, this review examines the efficacy and effectiveness of CAP in degrading PFASs by …


Facile Synthesis Of Tetraaryl Phosphonium Ionic Liquids, Stephanie C. Jones, Devin J. Schwaibold, Grant Meadows, Brennan Shuler, Richard E. Sykora, Frank Rolf Fronczék, James H. Davis, Benjamin Wicker Mar 2025

Facile Synthesis Of Tetraaryl Phosphonium Ionic Liquids, Stephanie C. Jones, Devin J. Schwaibold, Grant Meadows, Brennan Shuler, Richard E. Sykora, Frank Rolf Fronczék, James H. Davis, Benjamin Wicker

EKU Faculty and Staff Scholarship

The syntheses of triphenyl-2-pyridylphosphonium salts, [Mopyphos]A, where A-= BF4-, B(C6H5)4-, (CF3SO2)2N-, Sac-, and Ace-. (Sac-= saccharinate, Ace-= acesulfamate) are described. These salts can be synthesized on a multi-gram scale with good yields and have been characterized by NMR, single crystal XRD, and HRMS. Thermal analyses indicate that the bistriflimide (Tf2N-= (CF3SO2)2N-) salts are especially amenable towards high-temperature ionic liquid (IL) applications with decomposition temperatures above 450 degrees C. The synthetic methods described herein can be utilized to generate several phosphonium bistriflimide ILs of the general formula [(C6H5)3P-Ar]Tf2N, where Ar = N-heteroaryl).


Development, Optimization, And Validation Of A High-Sensitivity Capillary Zone Electrophoresis System For Bioanalytical Applications, Aaron I. Mena Mar 2025

Development, Optimization, And Validation Of A High-Sensitivity Capillary Zone Electrophoresis System For Bioanalytical Applications, Aaron I. Mena

Electronic Theses and Dissertations

Capillary zone electrophoresis (CZE) is a powerful analytical technique widely used for biomolecular separation due to its high resolution, efficiency, and sensitivity. This report presents the development and validation of a novel CZE system designed to improve modularity, reproducibility, and operational efficiency. The system integrates a laser-induced fluorescence (LIF) detection method with a 488 nm laser, enhanced fluid control through a negative pressure system, and a user-friendly GUI for automated operation and data acquisition. Performance verification included pressure stability tests, fluorescence accuracy assessments, and electrophoretic reproducibility studies. Comparative analysis with a previous CZE iteration confirmed improved baseline stability, peak resolution, …


Salmon As An Ecological Pathway Of Contaminants Into Alaskan Food Webs, Miranda Brohman, Gretchen Roffler, Dimitri G. Giarikos, David Kerstetter, Amy C. Hirons Mar 2025

Salmon As An Ecological Pathway Of Contaminants Into Alaskan Food Webs, Miranda Brohman, Gretchen Roffler, Dimitri G. Giarikos, David Kerstetter, Amy C. Hirons

SECLER Data

Salmon are important fish taxa for humans and animals in hemiboreal and subarctic ecosystems. Trace elements and their marine food web bioaccumulation raises biomagnification and potential human health risk concerns. Sixteen trace element concentrations and their health risk assessments were determined in seven different tissues of two Southeast Alaska salmon species (chum, Oncorhynchus keta and pink, Oncorhynchus gorbuscha). Chum tissues had overall higher trace element concentrations compared to pink, which may be attributed to a difference of diets, generally longer-lived and spending more time in the open ocean. All kidney and liver samples exceeded the tolerable daily intake for …


A Comparison Of Unconventional Microwave And Ultrasound-Assisted Extraction Methods Used For Flavonoids, Istiqomah Rahmawati, Daffa Hafiziaulhaq Azizi, Jihan Nafila Wibowo, Muhammad Reza, Boy Arief Fachri, Bekti Palupi, Meta Fitri Rizkiana, Helda Wika Amini, Ifan Ramadana, Felix Arie Setiawan Mar 2025

A Comparison Of Unconventional Microwave And Ultrasound-Assisted Extraction Methods Used For Flavonoids, Istiqomah Rahmawati, Daffa Hafiziaulhaq Azizi, Jihan Nafila Wibowo, Muhammad Reza, Boy Arief Fachri, Bekti Palupi, Meta Fitri Rizkiana, Helda Wika Amini, Ifan Ramadana, Felix Arie Setiawan

Makara Journal of Science

Cocoa pods (Theobroma cacao L.) are a rich source of flavonoids, which are natural antioxidants known for their health benefits. This study investigated the use of microwave-assisted extraction (MAE) and ultrasound-assisted ex-traction (UAE) to extract the maximum flavonoids and antioxidants from cocoa pods. MAE and UAE are efficient and sustainable methods for extracting bioactive compounds like flavonoids and antioxidants from cocoa pods, offer-ing faster extraction, reduced solvent use, and better compound preservation compared to conventional methods. These technologies unlock the untapped potential of cocoa pods for applications in food, cosmetics, and pharmaceuti-cals. The effects of extraction time (2–10 min), microwave …


Infrared Laser Ablation Of Biomolecules From Formalin-Fixed Tissue, Blessing Chisom Egbejiogu Mar 2025

Infrared Laser Ablation Of Biomolecules From Formalin-Fixed Tissue, Blessing Chisom Egbejiogu

LSU Doctoral Dissertations

In the research described in this dissertation, a high-precision infrared laser ablation microsampling method was utilized for spatially resolved proteomic and lipidomic analyses of formalin fixed paraffin embedded (FFPE) tissue, a widely used archival sample in biomedical research. Despite its extensive use, FFPE tissue presents challenges for proteomic analysis due to protein cross-linking and modifications introduced during fixation, which can hinder extraction and identification. Developing a streamlined high-resolution method to recover biomolecules from FFPE samples is critical for advancing biomarker discovery, retrospective studies, and multi-omics research. To address these challenges, this study employs an infrared (IR) laser ablation microdissection system …


A Bland–Altman Comparison Of The Lead Care® System And Inductively Coupled Plasma Mass Spectrometry For Detecting Low-Level Lead In Child Whole Blood Samples, Christina Sobin, Tanner Schaub, Natali Parisi, Eva De La Riva Mar 2025

A Bland–Altman Comparison Of The Lead Care® System And Inductively Coupled Plasma Mass Spectrometry For Detecting Low-Level Lead In Child Whole Blood Samples, Christina Sobin, Tanner Schaub, Natali Parisi, Eva De La Riva

Departmental Papers (PH)

Chronic childhood lead exposure, yielding blood lead levels consistently below 10 μg/dL, remains a major public health concern. Low neurotoxic effect thresholds have not yet been established. Progress requires accurate, efficient, and cost-effective methods for testing large numbers of children. The LeadCare® System (LCS) may provide one ready option. The comparability of this system to the “gold standard” method of inductively coupled plasma mass spectrometry (ICP-MS) for the purpose of detecting blood lead levels below 10 μg/dL has not yet been examined. Paired blood samples from 177 children ages 5.2–12.8 years were tested with LCS and ICP-MS. Triplicate repeat tests …


Refining Chlorosulfonation Methods For The Synthesis Of A Perfluoroalkyl Arylsulfonimide (Pfsi) Monomer, Ainsley P. Foster, Ben Varney, Hua Mei Mar 2025

Refining Chlorosulfonation Methods For The Synthesis Of A Perfluoroalkyl Arylsulfonimide (Pfsi) Monomer, Ainsley P. Foster, Ben Varney, Hua Mei

SPARK Symposium Presentations

Proton-exchange membrane (PEM) fuel cells are sources of energy that are clean, quiet, and highly responsive to changes in power needs, making them promising for use in automobiles and other portable power devices. The electrolyte of a PEM cell–the layer responsible for conductivity–is a polymer membrane, commonly consisting of perfluoroalkyl sulfonic acid (PFSA) polymers. In place of the PFSA polymers, perfluoroalkyl arylsulfonimide (PFSI) polymers are expected to improve the efficiency of PEM fuel cells with better stability and proton conductivity. The trifluovinylether (TFVE) aryl perfluorosulfonamide monomer is a new PFSI monomer proposed to fulfill these benefits once polymerized. The previous …


Consequences Of Oxidative Dna Damage: Base-Pair Dissociation, Singlet Oxygenation And Dna-Protein Crosslinking, May Myat Moe Feb 2025

Consequences Of Oxidative Dna Damage: Base-Pair Dissociation, Singlet Oxygenation And Dna-Protein Crosslinking, May Myat Moe

Dissertations, Theses, and Capstone Projects

8-Oxo-2′-deoxyguanosine (OG) is a common DNA lesion resulting from oxidatively generated damage and pairs with complementary cytidine (C) in Watson Crick base-pairing within duplex DNA. The WC-OG·C lesion, if not recognized or repaired, not only leads to G⋅C→T⋅A transversion mutations (through Hoogsteen (HG) base pairing of OG⋅A), but also renders the base pair being more vlunerable to ionizing radiation and singlet oxygen (1O2) damage. Leveraging on our previous accomplishments on the study of gas-phase reactions of 1O2 with 2′-deoxyguanosine radical cations, my research thesis expanded to the investigation of reaction dynamics of 9-methyl-8-oxoguanine (9MOG) radical cations. The experiments of following …


Investigating Dna Damage Caused By Reactive Oxygen And Nitrogen Species Via Guided-Ion-Beam Scattering And Computational Techniques, Jonathan Benny Feb 2025

Investigating Dna Damage Caused By Reactive Oxygen And Nitrogen Species Via Guided-Ion-Beam Scattering And Computational Techniques, Jonathan Benny

Dissertations, Theses, and Capstone Projects

Among DNA nucleobases, guanine (G) is the primary target for one-electron ionization and oxidation, generating G●+ through various processes, including photooxidation, electrocatalytic oxidation, DNA-binding transition metals, ionizing radiation, and photolysis. This is due to the low adiabatic ionization potential and oxidation potential of guanine. Electron holes from other nucleobases can move to guanine, proving that G●+ production traps oxidative DNA damage. G●+ formation can exacerbate DNA damages and cause secondary reactions from reactive oxygen species (ROS) and reactive nitrogen species (RNS) during pathological processes. The following three projects were conducted using a customized electrospray ionization (ESI) guided-ion-beam tandem mass spectrometer, …


In Memoriam - Nora Sabelli: Master Orchestrator Of Grant Programs And Mentor For Advancing The Interdisciplinary Learning Sciences Field, Eric Hamilton, Jeremy Roschelle, Roy Pea, Barbara Means, Louis Gomez, Kim Gomez, Nancy Butler Songer Jan 2025

In Memoriam - Nora Sabelli: Master Orchestrator Of Grant Programs And Mentor For Advancing The Interdisciplinary Learning Sciences Field, Eric Hamilton, Jeremy Roschelle, Roy Pea, Barbara Means, Louis Gomez, Kim Gomez, Nancy Butler Songer

Education Division Scholarship

On Friday, September 6, 2024, the learning sciences field lost a giant in Dr. Nora Sabelli, 87 years old, a personal mentor to many researchers and an inspiration to so many learning scientists and STEM leaders. Nora’s first professional career was as a computational chemist, and later she became a passionate leader in research for improving STEM education. Nora’s time as a senior program officer at the National Science Foundation’s (NSF) Education and Human Resources (EHR) directorate was legendary; she was a force of nature who reshaped funding priorities for stronger science and a stronger connection of science to education …


Antimicrobial Effect Of Herbs Extracted With Ethanol Compared To Ampicillin, Brianna Neilan, Laura Rowe Jan 2025

Antimicrobial Effect Of Herbs Extracted With Ethanol Compared To Ampicillin, Brianna Neilan, Laura Rowe

Posters-at-the-Capitol

Antibiotics are commonly used to treat bacterial infections within the medical field, however there are growing concerns of antibiotic resistance. Before the introduction of antibiotics herbs were commonly used to treat infections, and herbal medicine is still used in many communities and cultures. Bacteria’s increasing resistance to traditional antibiotics has caused herbal medicines to become a significant research topic recently. Methods of herbal medicine preparation include preparing teas using hot water, and tinctures that soak herbs in alcohol for several weeks. Previous research has shown significant antimicrobial effects of some herbs when soaked in water and other liquids. The aim …


Mechanism Of Napthenic Acid Binding To Dissolved Organic Matter, Clarissa Jules Jan 2025

Mechanism Of Napthenic Acid Binding To Dissolved Organic Matter, Clarissa Jules

Theses and Dissertations

The oil sands in Alberta, Canada are being destroyed by oil extraction because remediation methods have proven largely ineffective. One toxic byproduct of oil extraction is a family of cyclical surfactant organic acids known as naphthenic acids (NAs). They are toxic to aquatic life, including fish, frogs, and aquatic birds. It is suspected that NAs bind to humic acid, a major organic component of soil, in dissolved organic matter in natural water, making them difficult to remove by conventional remediation methods. This problem prompts the following question: what is the binding mechanism between NAs and humic acid when dissolved in …


Determining The Concentrations Of Trace Metals In Caffeinated Beverages By Icp-Aes, Lillian B. Gruss, James O'Donoghue, Maya Schram Jan 2025

Determining The Concentrations Of Trace Metals In Caffeinated Beverages By Icp-Aes, Lillian B. Gruss, James O'Donoghue, Maya Schram

Research and Creativity Symposium

A myriad of different caffeinated beverages are advertised and readily available to consumers. Previous research has identified the presence of elevated levels of metals unsafe for consumption in many of these beverages, energy drinks in particularly. We aim to analyze concentrations of chromium, aluminum, and lead, three such metals, in a variety of different caffeinated beverages. A calibration curve relating concentration of chromium, lead and aluminum to corrected peak height for five solutions of standardized concentration was created using a ThermoFisher iCAP 6000 Series. The same instrument was then used to analyze samples of eight different caffeinated beverages. The corrected …


Cold Atmospheric Plasma Induced Degradation Of Organophosphate Pesticides On Kevlar Swatches, Ta Chun Lin, Victor Somtochukwu Mbanugo, Boluwatife Stephen Ojo, Yue-Wern Huang, Marek Locmelis, Frank Daoru Han Jan 2025

Cold Atmospheric Plasma Induced Degradation Of Organophosphate Pesticides On Kevlar Swatches, Ta Chun Lin, Victor Somtochukwu Mbanugo, Boluwatife Stephen Ojo, Yue-Wern Huang, Marek Locmelis, Frank Daoru Han

Biological Sciences Faculty Research & Creative Works

Cold atmospheric plasma (CAP) was evaluated for degrading organophosphate pesticide (OP) residues (acephate, malathion, and dimethoate) from Kevlar fabrics. Fourier transform-Infrared (FTIR) spectroscopy, scanning electron microscope (SEM) imaging and tensile strength testing confirmed that CAP treatment preserved Kevlar's structural integrity and mechanical properties. Results show degradation efficiency increased with higher power, shorter discharge gaps, and longer exposure duration. Hyperspectral imaging supported the detection of plasma-induced spectral changes, reinforcing the presence of reactive species. The strong oxidative potential of CAP facilitated the rapid breakdown of OPs into nontoxic byproducts. These findings demonstrate the potential of CAP as a portable, energy-efficient solution …


Mass Spectrometry Combined With Chemical Biology To Study Human Ailments, Eric Thomas Jacquerio Davis Jan 2025

Mass Spectrometry Combined With Chemical Biology To Study Human Ailments, Eric Thomas Jacquerio Davis

Wayne State University Dissertations

Post-translational modifications (PTMs) are essential as chemical changes that regulate protein function, activity, stability, interactions, and localization after protein synthesis. PTMs, such as phosphorylation, acetylation, and ubiquitination, can activate or deactivate proteins, influence their interactions with other molecules, and determine their cellular location. This regulation is vital for numerous biological processes, such as cell cycle control, signal transduction, and gene expression. Abnormal PTMs are linked to various diseases in humans, including parasitic infection, blood disorders, cancers, and neurodegenerative diseases, making their study crucial for understanding disease mechanisms and developing targeted therapies. In the Pflum lab, we are interested in the …


Identifying The Constituents Of Pyrolysis Oil Using Supercritical Fluid Chromatography- Fraction Collection (Sfc-Fc) And Gas Chromatography- Mass Spectrometry/Vacuum Ultraviolet Spectroscopy (Gc-Ms/Vuv), Sadid Morshed Jan 2025

Identifying The Constituents Of Pyrolysis Oil Using Supercritical Fluid Chromatography- Fraction Collection (Sfc-Fc) And Gas Chromatography- Mass Spectrometry/Vacuum Ultraviolet Spectroscopy (Gc-Ms/Vuv), Sadid Morshed

2025 Fall Honors Capstones Projects - Archive

Plastic waste continues to accumulate as production increases and disposal methods remain insufficient. Even with recycling programs in place, much of the discarded plastic still ends up in landfills or waterways, eventually breaking down into harmful microplastics. One promising solution is the conversion of plastic waste into pyrolysis oil, which can also serve as an alternative feedstock for chemicals. Pyrolysis oil is produced by heating plastics to approximately 800 °C in the absence of oxygen, resulting in a complex mixture of hydrocarbons that includes paraffins, isoparaffins, olefins, naphthenes, and aromatics. Analyzing the amount of oxygen, nitrogen, and sulfur in these …


Complexometric Titration Of Terbium(Iii) Compounds: An Analytical Blast From The Past Gives Purity Assurance When Modern Instruments Fail Us., Jake E. Timbes, Cameron Bateman, Justin Stace Jan 2025

Complexometric Titration Of Terbium(Iii) Compounds: An Analytical Blast From The Past Gives Purity Assurance When Modern Instruments Fail Us., Jake E. Timbes, Cameron Bateman, Justin Stace

Science University Research Symposium (SURS)

Lanthanide ions have attracted attention for applications in microwave electronics, memory devices, lighting applications, and chemical sensors. Terbium(III)-centered homoleptic complexes show promise as potential fluorescence-based chemical sensing agents. Tb(phen)2(NO3)3 (phen = 1,10-phenothroline) exhibits striking visible emission when excited by short-wave ultraviolet light; this emission is completely quenched by exposure to water or strong acid. However, the luminescence returns under relatively benign conditions. Unfortunately, our array of terbium(III) complexes are notoriously insoluble; rendering standard analytical techniques useless to assess purity, notably, 1H and 13C-NMR. Titration is a useful technique to give us, an assurance of purity—in conjunction with the ad-hoc purity …


Estimating Vapor Pressures Of Pheromone Compounds Using Gas Chromatographic Retention, Bipasha Sarker Jan 2025

Estimating Vapor Pressures Of Pheromone Compounds Using Gas Chromatographic Retention, Bipasha Sarker

Chemistry & Biochemistry Theses - Archive

Accurate determination of the vapor pressures of organic materials is important for predicting the sample’s environmental impact. It is difficult to directly measure accurate and precise vapor pressures of chemical compounds with direct experimental methods. Thus, indirect or predictive models for estimating vapor pressures are used. In this study, we follow a gas−liquid chromatography (GLC)-based approach, where retention data is correlated with vapor pressure using multiple reference standards. The method (GLC-RTyS) requires temperature-dependent retention factors (k-values) for test compounds and reference standards with known vapor pressures at matching temperatures. It has been observed that reference standards selected according to functional …