Analytical Chemistry Commons^™

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.

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

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.

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.

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

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

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

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

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

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

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

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

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

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

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

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 …

Molecular Design And Engineering Of Luminophores For Aggregation Induced Electrogenerated Chemiluminescence, Jesy Alka Motchaalangaram

Dissertations

Most conventional luminophores produce intense emissions in solutions but suffer from weak emissions or quenching when aggregated in poor solvents due to intermolecular interactions, such as π-π stacking. This phenomenon is known as aggregation caused by quenching (ACQ), limits their applications in their solid state. In contrast, aggregation induced emission (AIE) is a phenomenon in which luminophores are weak- or non-emissive in solution but emit intensively in their aggregated or solid states. AIE has enabled significant advancements in various real-world applications and has inspired new areas of research. The combination of AIE with electrogenerated chemiluminescence (ECL) has resulted in a …

Mbse For Process Analytical Technology- Bwon Analysis Case Study, Arnaldo Garcia Cervantes

Open Access Theses & Dissertations

Volatile Organic Compound (VOC) emissions from industrial sources, particularly Benzene, present significant environmental and public health challenges. Regulatory frameworks, such as the U.S. Environmental Protection Agency’s Benzene Waste Operations NESHAP (BWON), mandate strict monitoring of control devices, specifically carbon adsorption canisters, to prevent emission breakthrough. However, current industry practices rely heavily on manual Method 21 testing, a labor-intensive process that creates lagging indicators and increases the risk of non-compliance events. This thesis proposes the design and development of an on-line, automated fugitive emissions monitoring system tailored for carbon canisters using Model-Based Systems Engineering (MBSE). Utilizing the Object-Oriented System Engineering Method …

Controlling Selectivity In Electrocatalytic Co2 Reduction With An External Magnetic Field., Nawaraj Karki

Electronic Theses and Dissertations

My dissertation describes how to alter the speciation and concentration of molecules at the electrode-electrolyte interface, and how those alterations affect reactivity and selectivity. This dissertation presents two distinct approaches to control the mass transport of neutral molecules such as carbon dioxide (CO₂) at the electrode-electrolyte interface by using an external magnetic field. The first finding demonstrates that magnetic fields indirectly affect the mass transport of target analytes such as CO₂ molecules by selectively interacting with charged species, such as hydroxide ions (OH^-). Such interaction induces magnetohydrodynamic (MHD) effects, which generate localized hydrodynamic flow and …

Development Of A Digestion Procedure Using Fe2+ Ions For Electrochemical Detection Of Mno2 Particles In Drinking Water, Kayla Elliott, Sarah Jane Payne, Zhe She

Journal of Electrochemistry

Developing methods for detection contaminants in drinking water is essential to ensuring that safe and acceptable quality drinking water is delivered to consumers. While manganese (Mn) was previously known only as a mere aesthetic issue, recent epidemiological data has shown to have negative neurological effects on humans, especially on children, prompting new health-based guidelines by Health Canada and the World Health Organization. In drinking water, Mn exists predominantly as Mn(II) and Mn(IV), and is regulated based on total Mn levels. Interestingly, measurement of Mn particulate using electroanalytical methods has not yet been reported in the literature. Herein, a digestion procedure …

Biocompatible And Antibacterial Pcl-Tio2@Ag/Γ-Cd Mof Nanocomposite Coating For Corrosion Resistance Of Magnesium Alloy In Simulated Body Fluid, Sara Dehghan-Chenar, Hamid R. Zare, Zahra Mohammadpour, Maryam Sadat Mirbagheri-Firoozabad

Journal of Electrochemistry

Magnesium alloys are promising candidates for bio-implant applications due to their biodegradability and biocompatibility. However, their rapid corrosion remains a critical limitation. This study presents the development of a multifunctional nanocomposite coating designed to enhance the corrosion resistance and antibacterial properties of magnesium alloy implants. The coating comprised γ-cyclodextrin metal-organic frameworks (γ-CD MOFs) decorated with TiO₂@Ag core-shell nanoparticles, embedded in a polycaprolactone (PCL) matrix. Immersion tests in a simulated body fluid (SBF) revealed an initially higher corrosion rate for the PCL-TiO₂@Ag/γ-CD MOF coating compared to the coating without TiO₂@Ag nanoparticles; however, it demonstrated significant …

The Relation Between Transport Properties And Solvation Structure For Electrolytes., Emanuel Naumann, Lalita Rai, Xingyi Lyu, Huong Nguyen, Tao Li

Honors Capstones

With continued progress in portable technology, energy storage has become an important factor to improve upon as batteries are found in a variety of everyday devices. Lithium-ion batteries are particularly common, although current technology features shortcomings in thermal stability, efficiency, and cost. Such shortcomings are related to current electrolytes in such technologies. The following experiment aims, for noteworthy alternative electrolytes, to analyze both macroscopic measurements related to transport properties and spectroscopy measurements that give insight into samples’ solvation structures. Such data are then used to identify the most promising electrolytes of the ones tested. Solutes tested include the promising imide-based …

Development Trends And Priority Research Fields Of Electrochemical Discipline In The 15th Five Year Plan Period, Lin Zhuang, Wen-Bin Cai, Heng-Xing Ji, Qing Li, Gong-Wei Wang, Sen Xin, Qing Zhao, Fang-Yi Cheng, Yu-Guo Guo, Lan-Qun Mao, Yang Tian, Fei Wu, Li-Min Zhang, Yan Xiang, Jin-Song Hu, Rui Cao, Li Xiao, Hua-Bing Tao, Wei Xing, Dong-Ping Zhan, Hong-Gang Liao, Mei-Ling Xiao, Bin Ren, Zhang-Quan Peng, Rui Wen, Xiang Wang, Yue-Feng Song, Hou-Fu Lv, Bao-Yu Xia, Guo-Xiong Wang, Jun Cheng, Zhi-Pan Liu, Min Zhou, Bing Huang, Cun-Pu Li, Yu-Qin Zou, Shuang-Yin Wang, Hai-Bo Lin, Zi-Dong Wei

Journal of Electrochemistry

In fulfillment of the national science-and-technology development agenda, the Department of Chemical Sciences of the National Natural Science Foundation of China (NSFC) convened the Strategic Symposium on the Fifteenth Five-Year (2026–2030) Development Plan for Electrochemistry held in Xiamen on 29 August, 2025—the culminating year of the Fourteenth Five-Year (2021–2025) Development Plan. More than forty leading experts in the field of electrochemistry participated with spanning nine thematic fronts: Interfacial Electrocatalysis, Interfacial Electrochemistry for Energy Storage, Bioelectrochemistry, Electrochemistry of Hydrogen Energy, Electrochemical Micro-/Nano-Manufacturing, Operando Electrochemical Characterization, Electro-Thermal Coupling Catalysis, Theoretical and Computational Electrochemistry, and Electrochemical Synthesis. The forum assembled China’s foremost electrochemical …

Day-Night Shifts In Water-Soluble Ions Of Size-Resolved Aerosols Before And After The Covid-19 Lockdown In A Coastal Megacity: Metro Manila, Philippines, Grace Betito, Paola Angela Bañaga, Rachel A. Braun, Maria Obiminda Cambaliza, Melliza Templonuevo Cruz, Alexander B. Macdonald, James Bernard Simpas, Connor Stahl, Armin Sooroshian

SOSE Affiliate: Manila Observatory

The COVID-19 pandemic-driven lockdowns offer a unique opportunity to examine how reductions in anthropogenic emissions impacted atmospheric aerosol composition in urban environments. This study investigates the day-night variability of size-resolved water-soluble ions in ambient particulate matter (PM) collected in Metro Manila before (November 2019–February 2020) and after (November 2020–February 2021) lockdown implementation. Using tandem Micro-Orifice Uniform Deposit Impactors (MOUDIs), aerosol samples were collected during daytime (06:00–18:00) and nighttime (18:00–06:00) periods and analyzed for key ionic species (sulfate, ammonium, nitrate, oxalate, sodium, chloride, calcium, and magnesium) via ion chromatography. Submicrometer water-soluble mass declined post-lockdown, particularly during daytime, reflecting suppressed secondary formation …

Improved Extraction And Detection Of Disinfection Byproducts, Impacts Of Wildland-Urban Interface Wildfires On Drinking Water, And Change In Disinfection Byproducts Over Time In Chlorinated Vs. Chloraminated Distribution Systems, Patrick Thomas Justen

Theses and Dissertations

Drinking water disinfection is critical to prevent the occurrence of waterborne pathogens in drinking water. However, disinfection causes the unintended formation of disinfection byproducts (DBPs) through the reaction of disinfectants (e.g., chlorine, chloramine) with natural organic matter (NOM), algal matter, or anthropogenic pollutants present in source waters. Exposure to DBPs is associated with increased bladder cancer, colorectal cancer, miscarriage, and birth defects. The U.S. EPA currently regulates eleven DBPs in drinking water—four trihalomethanes, five haloacetic acids, bromate, and chlorite. However, research shows that DBP related toxicity in drinking water is driven mainly by other, non-regulated DBPs, particularly iodinated DBPs and …

The Effect Of Ozone Treatment On The Quality Of Biodiesel From Waste Cooking Oil, Sri Redjeki Setyawati, Singgih Wibowo

Makara Journal of Science

This research demonstrates the successful production of biodiesel from waste cooking oil (WCO) using the transesterification method. A methoxide solution, formed by employing a base catalyst and alcohol, facilitated the conversion of triglycerides into methyl esters and glycerol as the byproduct. The conversion process yielded 74% biodiesel and 13.5% glycerol content, with the remaining proportion consisting of water and contaminants. The application of ozone (O₃) aeration proved effective in reducing contaminants—such as alcohol, unreacted catalysts, food residues and water—by approximately 60%. Furthermore, Fourier transform infrared (FTIR) testing affirmed that the biodiesel product—treated with O₃ aeration—maintained its original …

Quantification Of Terpenes In Various Commercial Cannabis Products By Gas Chromatography-Flame Ionization Detection And Gas Chromatography-Mass Spectrometry, Kaitlyn M. Ignaszak

Forensic Science Master's Projects

The goal of this research project was to identify and quantify the terpenes in five commercial cannabis products (dried bud, kief, two tinctures, and a pain cream) using gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Terpene identification and quantification were conducted using GC-MS and GC-FID, with a standard sample containing 21 terpenes of known concentrations. To determine the most effective extraction conditions, three organic solvents (ethanol, acetonitrile, and ethyl acetate) were employed. Additionally, the effects of extraction time on terpene yield were investigated by analyzing aliquots collected at five different time intervals, ranging from one hour to …

Development And Implementation Of Novel Mass Spectrometric Methods For Metabolism Studies In Drug Discoveries, Huifang Yao

Dissertations

The field of drug discovery has evolved significantly over the past few decades, with a growing emphasis on understanding the metabolic pathways and biotransformation processes that influence the pharmacokinetics and pharmacodynamics of drug candidates. Novel mass spectrometric methods have emerged as powerful tools in this domain, facilitating the comprehensive analysis of metabolic profiles and enabling the identification of metabolites with implications for safety, efficacy, and overall drug development. However, challenges remain in quantifying metabolic flux—an essential aspect of understanding drug action—particularly due to the limitations of traditional isotope kinetic assays, which often involve lengthy sample preparation and the use of …

Effect Of Seasonal Variability In Methane Emissions And Iron Redox Chemistry At Terrestrial-Aquatic Interfaces, Hermes C. Ruiz

Master's Theses

Methane (CH₄) emissions at terrestrial–aquatic interfaces (TAIs) are significant contributors to the global carbon budget, yet the mechanisms driving methanogenesis remain poorly understood. Limited data exist on how seasonal variations and redox processes influence CH₄ fluxes in these dynamic ecosystems. This study addressed two questions: (1) How are CH₄ fluxes in riverine floodplains and adjacent hillslopes impacted by seasonal variations? (2) What roles do metal redox processes (e.g., iron (Fe)) play in regulating methanogenesis?

In-situ CH₄ flux and solid-phase Fe speciation were quantified in East River, CO, under flooded and drained conditions. Groundwater chemistry, gas flux, and soil physical properties …

Simulating Chemiluminescence Spectra Of Oh Radical Using Quantum Dynamical Simulations, Triet M. Cao

Research from the Berry Summer Thesis Institute, 2025

Chemiluminescence is a phenomenon of light emission that occurs when molecules transition from an excited state to the ground state. This phenomenon is widely utilized in applications ranging from quantifying product yields in chemical reactions to biological imaging and atmospheric chemistry studies. It has also been used in many crucial applications in the scarce conditions of heat and electricity, such as light sources for astronomy discovery or deep-sea diving. A notable example of such reactions is combustion, where highly reactive hydroxyl radicals (OH) are products. These radicals exhibit a chemiluminescence spectrum because of the interaction between their ground state and …