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Full-Text Articles in Chemistry

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 …


Application Of Organic Geochemistry To The Characterization Of Hydrochar And Biochar: Insights Into Composition And Optimization, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Rubén Forján, José Luis Gallego Jan 2026

Application Of Organic Geochemistry To The Characterization Of Hydrochar And Biochar: Insights Into Composition And Optimization, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Rubén Forján, José Luis Gallego

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Hydrothermal carbonization has garnered significant attention in recent studies due to potential applications of the hydrochar produced, which overlap with those of torrefied biochar, including soil improvement, carbon sequestration, and energy production. However, unlike the relatively uniform properties of biochar, hydrochar characteristics can vary greatly depending on the feedstock used. Advanced characterization techniques are essential to better understand these materials and enhance their practical applications. Research on hydrochar requires a multi-faceted approach, including molecular-level studies, to optimize production processes and identify specific applications.

In this regard, analytical methods commonly used in organic geochemistry could play a crucial role in deepening …


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 …


Comprehensive Analytical Investigation Of Tetrahydro-4h-Chromene And Dihydropyridine Derivatives, Ryan J. Burk Jan 2026

Comprehensive Analytical Investigation Of Tetrahydro-4h-Chromene And Dihydropyridine Derivatives, Ryan J. Burk

Chemistry & Biochemistry Dissertations

Novel calcium channel blockers (CCBs) with dihydropyridine (DHP) or tetrahydro-4H-chromene moieties are often chiral, so effective enantiomer separation methods are needed for continued drug development. The purpose of this dissertation is to outline a comprehensive method development model for the chiral separations of DHPs and tetrahydro-4H-chromene derivatives. The scope of this dissertation is to address analytical challenges during initial synthesis, chiral separations, and data analysis during post-processing for this class of chiral compounds. The first section focuses on the method development strategies for separations of DHPs in the sub/supercritical fluid (SFC) and normal phase modes with the 2-hydroxypropyl-β-cyclodextrin stationary phase. …


Novel Methods For Environmental Fluoride Measurement, Cable Warren Jan 2026

Novel Methods For Environmental Fluoride Measurement, Cable Warren

Chemistry & Biochemistry Dissertations

Fluoride analysis has been an important focus of analytical analysis for many years and will continue to be so going forward. Today, fluorinated compounds, specifically per/polyfluoroalkyl substances (PFAS), better known as “forever chemicals” have captured the moment and are the subject of vast research and regulation. Under this context, I have researched new methods of fluoride separation and concentration in complex media as well as a novel method of PFAS destruction and total organic fluorine analysis for screening of PFAS in aqueous samples. Through research and work on micro-scale detection methods, an understanding of the state of the art and …


Absolute Quantification And Identification Of Rna From Rna-Lipid Nanoparticles Using High Resolution Mass Spectrometry, Jason C. Funderburk Jan 2026

Absolute Quantification And Identification Of Rna From Rna-Lipid Nanoparticles Using High Resolution Mass Spectrometry, Jason C. Funderburk

Theses and Dissertations

RNA therapeutics are a rising drug category with potential use for a range of conditions encompassing infectious diseases to therapies for cancer, diseases, and genetic disorders. RNA-lipid nanoparticles (RNA-LNPs) are the prominent delivery method for these therapeutics approved products include mRNA vaccines and polyneuropathy treatments. The emergency use authorizations and orphan drug status of current RNA-LNP drugs has allowed approval without finalization of the regulatory analytical procedures for quality monitoring. The objective of the study was to develop an LC-MS assay to simultaneously measure identity and concentration of two therapeutically relevant intact RNA constructs extracted from RNA-LNPs to enhance quality …


Nanostructured Cathode Catalysts For Aem Electrolysis: From Catalyst Design To Degradation And Hydrogen Dynamics, Yamini Kumaran Jan 2026

Nanostructured Cathode Catalysts For Aem Electrolysis: From Catalyst Design To Degradation And Hydrogen Dynamics, Yamini Kumaran

Electronic Theses & Dissertations (2024 - present)

Anion exchange membrane water electrolysis (AEMWE) presents a promising pathway toward cost-effective and sustainable hydrogen production by integrating the chemical robustness of alkaline systems with the compact, zero-gap design of proton exchange membrane electrolyzers. However, the widespread implementation of AEMWE is limited by the availability of highly active and durable platinum-group-metal (PGM)-free catalysts and by an incomplete understanding of their degradation behavior under realistic operating conditions.

This dissertation focuses on the development, characterization, and mechanistic investigation of nanostructured MoNi4–MoO2-based electrodes for efficient and stable hydrogen generation under alkaline and membrane-integrated environments. MoNi4–MoO2 nanorods …


Utilizing Coal For Mesophase Pitch-Based Carbon Fiber Production: Precursors, Processes, And Progress, Christina M. Thompson Jan 2026

Utilizing Coal For Mesophase Pitch-Based Carbon Fiber Production: Precursors, Processes, And Progress, Christina M. Thompson

Theses and Dissertations--Chemistry

Graphitic materials possess unique properties due to the unique combination of layered crystalline structure and carbon’s low atomic weight. High performance carbon fiber is one such example, displaying exceptional strength-to-weight ratios, stiffness, and thermal and chemical resistance. These properties render high performance carbon fiber a critical structural reinforcement material in the manufacture of composites across various industries, such as for automotive and aerospace applications. However, balancing fiber performance with precursor and processing costs remains a challenge. As alternative carbonaceous feedstocks are explored, coal has gained interest for utilization in graphitic products as a relatively abundant and low-cost source of aromatic …


The Deposition, Prevalence, And Persistence Of Gunshot Residue In Standard And Less Lethal Ammunition, Liliana Claire Barbosa Jan 2026

The Deposition, Prevalence, And Persistence Of Gunshot Residue In Standard And Less Lethal Ammunition, Liliana Claire Barbosa

Graduate Theses, Dissertations, and Problem Reports (ETD)

During the discharge of a firearm, gunshot residue (GSR) is released and settles into nearby surfaces, leaving traces that can provide valuable information for forensic investigations. This study aims to improve understanding of the deposition, prevalence, and persistence of standard and less-lethal ammunition through an analytical framework that examines collection and analysis protocols, revealing connections among multiple traces for effective use in investigations and courtroom proceedings.

Research into the chemical residues of less lethal ammunition (LLA) is a critical frontier in shooting investigations. While standard leaded ammunition has over a century of established literature, the chemical fingerprints of LLA residues …


Flexible Membrane Electrodes For Use In High-Capacity Lithium-Ion Batteries, David A. Denemark Jan 2026

Flexible Membrane Electrodes For Use In High-Capacity Lithium-Ion Batteries, David A. Denemark

College of Graduate Studies: Theses & Dissertations

Wearable electronic devices require high-capacity flexible batteries to improve user comfort and increase usage time per charge. In this thesis, flexible lithium-ion battery (LIB) electrodes are prepared using a novel and scalable phase inversion method, embedding one-dimensional SnO₂ nanowires and double-walled carbon nanotubes within a porous polyacrylonitrile asymmetric membrane. The optimized electrode delivered an initial specific discharge capacity of 915.93 mAh g⁻¹, approximately 2.5 times greater than conventional graphite anodes, with 61.99% capacity retention after 45 cycles. The incorporation of a carbon mesh substrate further enhanced both electrochemical and mechanical performance, achieving 89.46% capacity retention after 45 cycles and a …


Balancing Evidence Recovery: Hexane’S Effect On Biological And Non-Biological Traces In Sexual Assault Kits, Maya Richards Jan 2026

Balancing Evidence Recovery: Hexane’S Effect On Biological And Non-Biological Traces In Sexual Assault Kits, Maya Richards

Honors Undergraduate Theses

This study investigated the effectiveness of solvent – based extraction methods for the recovery of lubricant residues from simulated sexual assault swabs, with emphasis on balancing chemical evidence recovery. Sequential extraction using ultra – pure water followed by organic solvents, hexane, dichloromethane (DCM), and ethyl acetate (EA), was evaluated across water – based, silicone – based, oil – based, and hygiene product matrices. Analysis was performed using Direct Analysis in Real Time – High Resolution Mass Spectrometry (DART – HRMS), and extraction efficiency was assessed through spectral correlation with neat reference samples. Results demonstrated that solvent performance was highly dependent …


Design, Synthesis, And Characterization Of Phosphonate-Functionalized Diimide Ligands For Metal-Organic Framework Construction, Kenya Rosas, Jonathan Uribe Jan 2026

Design, Synthesis, And Characterization Of Phosphonate-Functionalized Diimide Ligands For Metal-Organic Framework Construction, Kenya Rosas, Jonathan Uribe

Posters - 2026

  • Metal–organic frameworks (MOFs) are solid, porous materials composed of metalions reacted with organic linkers
  • MOFs are customizable through variations in their metal ions, organic linkers, and the functional groups of the organic linker all yielding a structure with different properties
  • MOFs have a variety of applications, ranging from storage and catalysis to drug delivery
  • The synthesis and characterization of four phosphonate-based diimide ligands:
    • N,N´-bis(phosphonomethyl)-pyromellitimide (PPMI).
    • N,N´-bis(phosphonobenzyl)-pyromellitimide (PPMI-Ph).
    • N,N´-bis(phosphonomethyl)-3,3′,4,4′-biphenylenediimide (PBDI).
    • N,N´-bis(phosphonobenzyl)-3,3′,4,4′-biphenylenediimide (PBDI-Ph).
  • These ligands were then coordinated with zinc or copper metal ions to make MOFs.


De Novo Protein Binding To Zinc Oxide Through Biomineralization Pathways, Jean-Mark A. Francis Jan 2026

De Novo Protein Binding To Zinc Oxide Through Biomineralization Pathways, Jean-Mark A. Francis

Theses and Dissertations

De novo proteins are structurally distinct from proteins found in nature and thus capable of having their amino acid sequence modified to accomplish tasks such as increasing protein-nanoparticle binding without unfolding or decomposing. Zinc Oxide nanoparticles are functionally distinct from their bulk counterparts and are widely used as semiconductors in a variety of fields such as medicine and agriculture. With demand for these nanoparticles increasing, environmentally sustainable methods of Zinc Oxide nanoparticle synthesis are being investigated as an eco-friendly alternative to currently utilized but environmentally hazardous chemical and physical techniques. This research investigates the binding characteristics between Zinc Oxide nanoparticles …


Design, Syntheses And Biological Applications Of Fluorescent Probes For Nad(P)H, Hsa And Cellular Microenvironment Sensing, Adenike M. Olowolagba Jan 2026

Design, Syntheses And Biological Applications Of Fluorescent Probes For Nad(P)H, Hsa And Cellular Microenvironment Sensing, Adenike M. Olowolagba

Dissertations, Master's Theses and Master's Reports

Fluorescent probes have emerged as powerful tools for investigating complex biological processes due to their high sensitivity, selectivity, and capability for real-time, non-invasive imaging. In particular, the detection of key biomolecules such as NAD(P)H, viscosity-related parameters, human serum albumin (HSA), and pH is essential for understanding cellular metabolism, redox homeostasis, and disease progression. In Chapter 2, three coumarin-based fluorescent probes (A–C) were designed, synthesized, and characterized for monitoring NAD(P)H levels in living cells. Probes A and B feature coumarin–cyanine hybrid structures linked via vinyl and thiophene bridges to 3-quinolinium acceptors, respectively, while probe C incorporates a dicyano moiety to replace …


Physicochemical, Pharmacognostic Standardisation And Phytochemical Analyses Of The Homoeopathic Drug Justicia Adhatoda, Bibaswan Biswas, Satish Patel, Digvijay Verma, Satyajit Maity, Shilpi Singh, Paulami Majumdar, Narasimha Kumar Gv Dec 2025

Physicochemical, Pharmacognostic Standardisation And Phytochemical Analyses Of The Homoeopathic Drug Justicia Adhatoda, Bibaswan Biswas, Satish Patel, Digvijay Verma, Satyajit Maity, Shilpi Singh, Paulami Majumdar, Narasimha Kumar Gv

Indian Journal of Research in Homoeopathy

Background: Justicia adhatoda (J. adhatoda), also well known as Vasaka in India is a medicinal plant chiefly used to treat respiratory ailments in traditional and alternative medical systems. Objective: This study aimed to establish the physicochemical, pharmacognostic, and phytochemical standardisation parameters of the drug. The study involved the measurement of physicochemical parameters and chemical profiling of the raw drug. The chemical characteristics of the in-house mother tincture (prepared from in-house raw drug) and commercial mother tinctures available in India were also evaluated to assess the quality of commercially available mother tinctures. Materials and Methods: The present study …


Two Members Of The Editorial Board Of Journal Electrochemistry, Kai Wu Elected As An Academician Of The Chinese Academy Of Engineering And Yi Cui A Foreign Academician Of The Chinese Academy Of Sciences, Editorial Office Of J.Electrochem. Dec 2025

Two Members Of The Editorial Board Of Journal Electrochemistry, Kai Wu Elected As An Academician Of The Chinese Academy Of Engineering And Yi Cui A Foreign Academician Of The Chinese Academy Of Sciences, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Electrochemical Characterization And Modulation Of Biological Processes, Yue-Qi Li, Wei-Hua Huang, De-Chen Jiang, Bao-Hong Liu, Bin Su, Yang Tian, Jing-Juan Xu, Ping Yu, Feng Zhao, Huang-Xian Ju, Jing-Hong Li Dec 2025

Electrochemical Characterization And Modulation Of Biological Processes, Yue-Qi Li, Wei-Hua Huang, De-Chen Jiang, Bao-Hong Liu, Bin Su, Yang Tian, Jing-Juan Xu, Ping Yu, Feng Zhao, Huang-Xian Ju, Jing-Hong Li

Journal of Electrochemistry

Electrochemical processes lie at the core of biological function, governing energy transduction, metabolic flux, and molecular signaling. Recent advances in electrochemical science now allow these processes to be probed and controlled with unprecedented spatial, temporal, and chemical resolution. In this review, we present an integrated framework that progresses from fundamental mechanisms to analytical technologies and functional modulation. We begin by outlining electron transfer pathways in mitochondrial respiration, microbial extracellular electron transfer, and DNA- and protein-based charge conduction, followed by the principles of photon-electron conversion in photosynthesis and the central role of redox equilibrium in coordinating cellular responses. We then highlight …


Journal Of Electrochemistry Officially Indexed By Leading Oa Databases Oarl And Coaj, Editorial Office Of J.Electrochem. Dec 2025

Journal Of Electrochemistry Officially Indexed By Leading Oa Databases Oarl And Coaj, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Feature Column Of Journal Of Electrochemistry Nominated For 2025 Top 10 Famous Columns Of Fujian Provincial Newspapers And Periodicals, Editorial Office Of J.Electrochem. Dec 2025

Feature Column Of Journal Of Electrochemistry Nominated For 2025 Top 10 Famous Columns Of Fujian Provincial Newspapers And Periodicals, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Enzyme-Free Colorimetric Sensing Of Glucose Using Silver Nanoparticles With A Green Stabilizing Agent From Capsicum Chinense Jacq Extract, Boyfannie Ivan Putra, Hermin Sulistyarti, Muhammad Mashuri Utama, Aura Ananda Haryanto, Rurini Retnowati, Mohamad Rafi, Akhmad Sabarudin Dec 2025

Enzyme-Free Colorimetric Sensing Of Glucose Using Silver Nanoparticles With A Green Stabilizing Agent From Capsicum Chinense Jacq Extract, Boyfannie Ivan Putra, Hermin Sulistyarti, Muhammad Mashuri Utama, Aura Ananda Haryanto, Rurini Retnowati, Mohamad Rafi, Akhmad Sabarudin

Makara Journal of Science

Diabetes mellitus (DM) is a significant global health issue characterized by abnormal glucose levels in the human body. DM diagnostics are often based on invasive sampling from blood, which poses a potential risk of infection and tissue damage. Therefore, a non-enzymatic and non-invasive method for glucose monitoring is demanded as a simple alternative to glucose detection in urine samples. In this work, enzyme-free glucose determination is based on the formation of silver nanoparticles stabilized by Capsicum chinense Jacq extract (CCJ-AgNPs). Under alkaline conditions, glucose functions as a reducing agent for silver ions, and the extract acts as a stabilizer to …


Suitability Of Mobile Phase Recycling For Methylxanthine Quantification In Coffee Samples Using Hplc, Kaitlin O’Keeffe, Marcos Mariano, Brian Murphy Dec 2025

Suitability Of Mobile Phase Recycling For Methylxanthine Quantification In Coffee Samples Using Hplc, Kaitlin O’Keeffe, Marcos Mariano, Brian Murphy

SURE Journal: Science Undergraduate Research Experience Journal

Caffeine, theobromine and theophylline fall under a drug class known as methylxanthines. These three compounds are of major interest in the food industry due to their presence in popular foods and beverages such as tea, coffee, and chocolate. As these compounds can cause physical and mental stress at high dosages, their quantification is essential to ensure product safety and quality. Here, we describe an eco-friendly HPLC method developed to quantify the amount of these analytes in coffee samples sourced across the SETU Waterford, Cork Road campus. Using an isocratic mixture of water and methanol, a mobile phase recycling approach was …


Spilling The Tea: Effects Of Uv Disinfection On Bioactive Compounds In South African Rooibos Tea, Sora Ghanem, Leah Ankiah, Yusra Ahmed Dec 2025

Spilling The Tea: Effects Of Uv Disinfection On Bioactive Compounds In South African Rooibos Tea, Sora Ghanem, Leah Ankiah, Yusra Ahmed

Student Scholar Symposium

This study investigated the effects of ultraviolet (UV) light disinfection on key bioactive flavonoid compounds in rooibos tea (Aspalathus linearis). There is an interest in non-thermal food preservation technologies, and UV treatment offers potential advantages for beverage processing. However, concerns exist regarding possible degradation of health-promoting compounds during treatment. Rooibos tea samples were subjected to five UV exposure intensities (0, 25, 50, 75, and 100 mJ/cm²), and concentrations of four major flavonoids (aspalathin, orientin, vitexin, and rutin) were measured using high performance liquid chromatography (HPLC). Surprisingly, most flavonoids showed stability or slight concentration increases at higher UV doses. Aspalathin concentrations …


Unveiling Hidden Hazards: A Complementary Approach To Affordable Non-Destructive Heavy Metal Detection, Mario Faragalla, Gulsin Barwari, Makenzie Brinkoeter, Eimy Lozano-Fuentes, Isabelle Riera Dec 2025

Unveiling Hidden Hazards: A Complementary Approach To Affordable Non-Destructive Heavy Metal Detection, Mario Faragalla, Gulsin Barwari, Makenzie Brinkoeter, Eimy Lozano-Fuentes, Isabelle Riera

Student Scholar Symposium

History has bestowed upon us vast treasures, with the Victorian Era offering a wealth of gifts, such as vibrant art and even secrets preserved in books of this period. However, concealed within the pigments that bring these works to life lie heavy metals. Not only do they pose significant health risks, but they can also be found within these pieces centuries later. Intrigued by the Winterthur project, Beaman librarians, Jan Cohu and Kayla Rutledge, discovered that our library housed some of these Victorian Era books. From there, the Beaman staff sent an inquiry to the chemistry department and Dr. Weinstein-Webb …


Fermented Foul Play: A Real-World Forensic Scenario To Enhance Student Engagement And Understanding Of Instrumentation And Analytical Data Analysis, Abigail Hoermann, Laci Joy Walmer, Matthew J. Goss Dec 2025

Fermented Foul Play: A Real-World Forensic Scenario To Enhance Student Engagement And Understanding Of Instrumentation And Analytical Data Analysis, Abigail Hoermann, Laci Joy Walmer, Matthew J. Goss

Student Scholar Symposium

A forensic-style investigation was introduced in an upper-level instrumental analysis course to foster collaboration and application of theoretical concepts in a laboratory setting. Students were provided with kombucha samples collected from a simulated crime scene and tasked with determining ethanol concentrations using Gas Chromatography–Mass Spectrometry (GC-MS). By independently preparing serial dilutions, establishing calibration curves, and interpreting mass spectra, they practiced quantitative analytical techniques and engaged in evidence-based problem solving. Notably, Sample C demonstrated elevated ethanol levels (6.4% v/v), suggesting possible adulteration and deepening the forensic narrative. Through this scenario-driven format, students strengthened both their technical competencies and their ability to …


Integrating Multimodal Analysis For Chemical Detection In Victorian Bookcloth: Correlations, Advantages, And Limitations, Leila Ais, Abigail L. Hoermann, Jafer Aljorani Dec 2025

Integrating Multimodal Analysis For Chemical Detection In Victorian Bookcloth: Correlations, Advantages, And Limitations, Leila Ais, Abigail L. Hoermann, Jafer Aljorani

Student Scholar Symposium

The detection of heavy metals in Victorian textiles presents a set of unique analytical challenges that cannot be addressed through usage of a single modality. Here, we detail a novel multimodal analytical approach that integrates distinct yet complementary instrumentation: inductively coupled plasma-optical emission spectroscopy (ICP-OES) offering precise quantitative elemental analysis, portable X-ray fluorescence (pXRF) enabling rapid, affordable, and non-destructive detection, electron dispersive spectroscopy – scanning electron microscopy (EDS-SEM) mapping elemental distributions and sample topography, and X-ray diffraction (XRD) revealing crystalline structures. This comparative study highlights the strengths and limitations of each analytical technique, demonstrating how their combined use provides a …


Photoflow Synthesis And Characterization Of Cis- And Trans-N-Isohumulone, Gregory M. Giovine, Bradley Gallow, Trevor Smith, Bruce Hamper Dec 2025

Photoflow Synthesis And Characterization Of Cis- And Trans-N-Isohumulone, Gregory M. Giovine, Bradley Gallow, Trevor Smith, Bruce Hamper

Undergraduate Research Symposium

Previously published efforts by the Hamper group demonstrated the viability of photochemistry in the isomerization of n-humulone to n-isohumulone. Photochemical isomerization reactions of n-humulone performed under 400nm light over 8 hours resulted in high yields (84% reported) of largely trans-n-isohumulone (>95%). These promising results invited further examination of the photochemical process and the application of photoflow procedure. Herein we report the beginnings of a comprehensive slate of n-humulone isomerization reactions performed under iterative photoflow conditions.


Health Implications Of Heavy Metal Contamination In Commercially Available Deodorant And Antiperspirant Products Sold In Benghazi, Libya, Maysson Yaghi, Khaled Elsherif Dec 2025

Health Implications Of Heavy Metal Contamination In Commercially Available Deodorant And Antiperspirant Products Sold In Benghazi, Libya, Maysson Yaghi, Khaled Elsherif

Al-Bahir

The extensive usage of deodorants and antiperspirants raises concerns about the potential health risks posed by heavy metal content. This study quantified the levels of five heavy metals: Aluminum, Zirconium, Lead, Cadmium, and Chromium in 22 commercial products widely used in Benghazi, Libya, and assessed the associated health risks. Samples, categorized into gel, stick, and roll-on formulations, were analyzed using iCAP TQ ICP-MS. Al and Zr showed the widest concentration ranges, reflecting their intentional use as active ingredients. Al levels ranged from trace amounts (0.032 mg/kg) up to a maximum of 99.10 mg/kg, while Zr was found exclusively in gel …


Inductively Heated Platinum Electrodes, Jayamini Madumali Mudugamuwa Hewage Dec 2025

Inductively Heated Platinum Electrodes, Jayamini Madumali Mudugamuwa Hewage

Theses and Dissertations

This dissertation presents the fabrication and application of a 150 micrometer platinum microelectrode for induction heating, with a copper coil generating the electromagnetic field and the heating process controlled using pulse width modulation technique (PWM) to regulate the duty cycle of a high-frequency signal. Electrochemical characterization, including resonance frequency determination, peak-to-peak potential optimization, and scan rate variation, is conducted using a 5 mM [Ru(NH3)6]2+/3+ solution in 0.1 M KNO3 to calibrate current variations with changing duty cycles, while the temperature increase (delta T) is estimated using the Seebeck coefficient of [Ru(NH3)6]2+/3+. The study further explores the application of induction heating …


Buffer Vs. Swabs: Efficacy Of Carrier Nucleic Acids In Robotic Extractions, Shawn Cecil Dec 2025

Buffer Vs. Swabs: Efficacy Of Carrier Nucleic Acids In Robotic Extractions, Shawn Cecil

Honors Projects

This study compared the efficiency of two carrier nucleic acid methods, specifically using salmon sperm DNA (spDNA), in robotic solid-phase extractions of cotton swab samples. Robotic extractions reduce processing time and workload but result in substantially lower DNA recovery than manual organic extraction. This research tested 10 µg of spDNA being added to the lysis buffer or pre-treating the swabs with it before DNA was added. Both methods showed a significant increase in recovery compared to extractions with no carrier. In the buffer extractions, recovery ranged from 69.4% to 117.5% and the swabs being pre-treated ranged from 84.2% to 125.8% …


The Malonate Template: The Key To Unlocking Novel Amino Acids, Thomas Owens Dec 2025

The Malonate Template: The Key To Unlocking Novel Amino Acids, Thomas Owens

Dissertations

The “Malonate Template” provides access to various amino acids, all from a common intermediate. Herein, demonstrates the use of the malonate template to establish a synthetic route to both 2-thiohistidine and 2-thio-3-N-methyl-histidine from a benzyl methyl malonate derived intermediate. Furthermore, efforts exploiting the applicability of the malonate template for the of both 2-thiohistidine and 2-thio-3-N-methyl-histidine as a suitable alternative to methods previously described by Erdelmeier are described.

The method presented incorporates modifications to the biomimetic pathway described by Erdelmeier for the synthesis of 2-thiohisidine. By exploiting the biomimetic formation of 2-thiohisitidne’s mechanism via mass spectrometry, we …