Chemistry Commons^™

High-Throughput Optical Analysis To Inform Design Of Electrochemical Biosensors, Nathan J. Ricks, Michael A. Pence, Monica Brachi, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Electrochemical biosensors are central to wearable diagnostics, point-of-care testing, and continuous health monitoring due to their low power requirements, compatibility with miniaturized electronics, and proven clinical impact. Despite these advantages, the development of new electrochemical biosensors remains slow, constrained by limited throughput, complex electrode–biomolecule interfaces, and challenges associated with selectivity and performance in chemically complex environments. This perspective outlines how the next generation of electrochemical biosensors can be enabled by decoupling high-throughput front-end discovery and optimization from electrochemical readouts using nonelectrochemical surrogate assays. Optical, affinity, and cell-sorting platforms, including SELEX, fluorescence-activated cell sorting, and chemically coupled fluorescence assays, allow orders-of-magnitude …

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 …

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 …

Deciphering The Role Of Binder Reaction Exothermicity In Thermal Runaway Of Lithium-Ion Cells, Wen Wen, Jing-Hong Zhou, Hao-Tian Lu, Xing-Gui Zhou

Journal of Electrochemistry

Thermal safety associated with lithium-ion cells as power sources remains a critical industry concern. A comprehensive understanding of how internal exothermic side reactions contribute to temperature rise is fundamental for accurately analyzing thermal runaway processes and predicting the thermal safety of lithium-ion cells. While various side-reactions, such as decomposition of solid electrolyte interphase layer, reaction between anode materials and electrolyte, reaction between cathode materials and electrolyte, and electrolyte decomposition, have been identified as heat generation sources in previous studies, the quantification of these reactions remains insufficiently standardized. Particularly, the impact of heat generation from binder decomposition (most commonly polyvinylidene difluoride) …

Determination Of Trace Amounts Of Pb2+ And Cu2+ Ions In The Ohio River With Anodic Stripping Voltammetry And Flame Atomic Absorption Spectroscopy To Test Water Contamination From Factories., Eliana Purcell

The Cardinal Edge

In this project, water near factories in Rubbertown, Louisville, KY were tested to see if a significant enough amount of waste is deposited in the Ohio River that the concentrations of Pb2+ and Cu2+ exceed the maximum contaminant levels the World Health Organization (WHO) and the United States Environmental Protection Agency (EPA) have set in place. Waste from industrial factories may contain contaminants that have negative effects on aquatic ecosystems and even human health, so two potentially harmful metal ions were tested. The concentration of Cu2+ in water samples was detected through flame atomic absorption spectroscopy (FAAS), and the concentration …

Characterization Of Ru(Ii) Polypyridyl Photosensitizers Bound To Tio2 Supports Through A New Covalent Metal-Ester Bonding Motif, D. M. S. C. Dissanayake, Christopher T. Lebarron, Laura C. Maybach, Joseph J. Kuchta Iii, Seyyedamirhossein Hosseini, Aaron K. Vannucci

Faculty Publications

The development of photoelectrochemical (PEC) devices involves the attachment of molecular photosensitizers onto solid supports. Particularly significant to this work are PECs that rely on ruthenium-based photosensitizers on high band gap metal oxide (MOx) supports. In this study, we have explored a new ester binding motif (MOx-ester) to covalently attach a ruthenium polypyridyl photosensitizer to TiO₂. This new MOx-ester photoanode is compared to the traditional photoanodes that utilize acid/base binding groups to attach the molecular Ru sensitizers to TiO₂. The new MOx-ester binding motif is characterized by cyclic voltammetry UV-Vis, solid state ¹³C NMR, and …

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 …

Electrochemical Breath Sensors In Medical Diagnostics: Emerging Trends And Future Directions, Natalie E. Strom, Courtney J. Weber, Olja Simoska

Faculty Publications

With the rising prevalence of metabolic diseases, infections, and mental health disorders, there is a growing demand for noninvasive diagnostic tools that enable early detection and continuous health monitoring. In this context, exhaled breath biomarkers provide insight into physiological and pathological processes. Electrochemical breath sensors (EBSs) have emerged as a promising platform for rapid, real-time, and cost-effective disease tracking via the detection of volatile breath biomarkers, such as NH₃, NO, and CO₂. Recent advancements in electrode materials, biological recognition elements, and sensor architectures—spanning nanomaterials, enzymes, aptamers, and molecularly imprinted polymers—have enhanced the analytical performance of EBSs. …

Electrochemical Breath Sensors In Medical Diagnostics: Emerging Trends And Future Directions, Natalie E. Strom, Courtney J. Weber, Olja Simoska

Faculty Publications

With the rising prevalence of metabolic diseases, infections, and mental health disorders, there is a growing demand for noninvasive diagnostic tools that enable early detection and continuous health monitoring. In this context, exhaled breath biomarkers provide insight into physiological and pathological processes. Electrochemical breath sensors (EBSs) have emerged as a promising platform for rapid, real-time, and cost-effective disease tracking via the detection of volatile breath biomarkers, such as NH₃, NO, and CO₂. Recent advancements in electrode materials, biological recognition elements, and sensor architectures—spanning nanomaterials, enzymes, aptamers, and molecularly imprinted polymers—have enhanced the analytical performance of EBSs. …

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 …

Aptamer Selection And Development Of Electrochemical Aptamer-Based Sensors For Neuropeptide Y, Evelyn Adela Carreto Guevara

Department of Chemistry: Dissertations, Theses, and Student Research

In this thesis, we report the results of four aptamers obtained from an aptamer selection process called the systematic evolution of ligands by exponential enrichment (SELEX) with affinity to Neuropeptide Y (NPY). NPY is a highly abundant peptide transmitter with widespread distribution throughout the body which affects various physiological functions. These functions include energy homeostasis, appetite regulation, stress response, and anxiety regulation. Dynamic monitoring of NPY levels is crucial for better understanding behaviors in individuals with neurological disorders associated with NPY. Aptamers are synthetic oligonucleotides obtained through SELEX which have a binding affinity to a target of interest when in …

Electropolymerization Of Nile Blue And Toluidine Blue Dyes For Hydrogen Evolution Reaction Electrocatalysts, Camellia N. Schwartzman

Macalester Journal of Physics and Astronomy

This work investigated electropolymerized (EPD) organic conductive polymers poly-Nile Blue (PNB) and poly-Toluidine Blue (PTB) on fluorine-doped tin oxide (FTO) glass substrates as electrocatalysts for the hydrogen evolution reaction (HER). We investigated the effect of changing the heteroatoms in the pi-conjugated structure of poly-Neutral Red (PNR). UV-vis spectroscopy was used to estimate film thickness. Catalytic activity was quantified by Tafel slope and formal redox potential. PNB and PTB exhibited low current densities and small standard rate constants. Although neither showed highly active catalysts for HER, future directions should continue to pursue structures similar to PNR for HER electrocatalysts.

Electrocatalytic Degradation Of Methylene Blue Using Graphene Oxide, Antimony Oxide, And Graphene Oxide-Supported Antimony Oxide Ink-Based Electrodes, Maria Irene Myers Armas

Theses and Dissertations

This study investigates the electrocatalytic degradation of methylene blue (MB) using copper mesh electrodes coated with graphene oxide (GO), antimony oxide (Sb₂O₃), and their composite (GO/Sb₂O₃). These materials were evaluated across a pH range of 2 to 8 using sodium sulfate as the supporting electrolyte. UV-Vis spectroscopy at 665 nm confirmed dye degradation, with removal efficiencies reaching up to 95% at pH 2. However, degradation decreased at higher pH, with 40 – 60% removal at pH 8, depending on the electrode. Kinetic analyses revealed optimum performance under acidic conditions. GO/Sb₂O₃ electrodes demonstrated the most consistent and effective performance across all …

Quinone-Mediated Extracellular Electron Transfer In Escherichia Coli During Glucose Oxidation Metabolism, Megan Danielle Whisonant

Theses and Dissertations

The growing global demand for energy, ongoing reliance on fossil fuels, and increasing water pollution from industrial and anthropogenic sources present significant environmental challenges. In response to these issues, renewable and sustainable energy sources offer substantial potential for reducing dependence on fossil fuels and ensuring access to clean water. Microbial electrochemical systems (MESs) have emerged as promising, eco-friendly solutions for energy-efficient wastewater treatment and bioremediation. A key challenge in MESs development is facilitating effective electron transfer between microorganisms and electrode surfaces. The first chapter of this thesis discusses the fundamentals of MES types, explains mechanisms of extracellular electron transfer, and …

Chemical And Physical Characterization Of Verbenaceae Essential Oils Using Modern Analytical Methods And Chemometrics, Aleksandra N. Hilliard

Master's Theses

Essential oils have been used for generations to treat various health issues, including mitigating insomnia, reducing stress, inflammation, and preserving foods, to mention a few. Essential oils have complex chemistry, which defines the essence of the host plant. Recently, increased commercial uses of essential oils have prompted attention at the governmental level to monitor the chemical, physical, or biological activity of essential oils. This study is an attempt to add new information for consumers to the understanding of the composition of essential oils.

Modern analytical techniques including FTIR-ATR, GC-MS, LC-MS-MS, multivariate analysis statistics, and physio-chemical techniques (electrochemistry, DPPH, TRC, and …

Benchtop-Scale High Temperature Molten Salt Electrochemical Reactors: Experimental Setup And Considerations, Haley Hoover, Ivy Wu, Oluwatamilore Olushina, Robert Bell, Kerry Rippy

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

Molten salt electrochemical reduction (MSER) is the dominant production method for aluminum and titanium, and emerging technologies for producing other commodity metals with these highly electrified techniques have demonstrated promising results. However, the scale up of MSER of materials such as iron and silicon are limited by the challenging issues of materials compatibility and impurity control. This work describes an experimental MSER setup using both chloride and carbonate salts. This setup is designed for operations outside of a glovebox, which is practical from an industrial perspective, but creates unique challenges. This work serves as a practical guide to discuss some …

Synthesis, Characterization, And Redox Properties Of Select 1,4-Diazocine-6,11-Diones Towards An Electrochromic Dye-Set, Jeffrey Scott Richards

Open Access Theses & Dissertations

The daily consumption of personalized digital visual information depends on the current purview of electronic-based displays. Present manufacturers utilize modern technologies, such as LCD, OLED, QLED, and electronic ink, or "E Ink," in their devices to display text, pictures, and other forms of media to individual users. However, as modern society continues to rely on the use of digital displays, the demand for low-power alternatives will continue to rise as their application in varying scenarios is realized. Currently, "E Ink" technology continues to grow as the dominant solution in the e-readers and digital signage marketplace, and can even be seen …

Synthesis And X-Ray Characterization Of Nickel Phosphide Nanostructures For Water Oxidation, David Thompson

Graduate Theses and Dissertations

The pursuit of earth-abundant 3d transition metal catalysts for alkaline water electrolysis remains an active area of research. While NiFe layered double hydroxides (LDH) are currently the most active catalysts for the oxygen evolution reaction (OER), doping Ni-based catalysts with phosphorus to form Ni metal phosphides has emerged as a promising alternative. However, the complex crystalline and amorphous phases of NiP_x have hindered their characterization, and the OER mechanism and origin of activity remain unclear. This dissertation aims to elucidate the synthesis, OER performance, and in situ reconstruction of amorphous NiP_x-based nanomaterials, with a focus on in …

Photocathodes From Aerobic Oxidation Of Tellurorhodamines, Amelia Jellison

Dissertations and Theses

Growing environmental concerns have facilitated an increased need for renewable energy. Solar energy is an excellent source of renewable energy, however current dye-sensitized solar cells are not efficient enough for commercial use. This thesis attempts to create a novel dye-sensitized cathode to increase the efficiency of dye-sensitized solar cells.

Dye-sensitized cathodes could lower the energy level on the cathode and thereby increase the overall efficiency of the solar cell, however until now it has not been attempted. A tellurorhodamine dye with a mesityl ring was chosen as the dye for its ability to aerobically oxidize in the presence of light. …

Epitaxial Growth Of Metal-Organic Framwork Thin Films By Electro-Conversion And Electrodeposition, Xiaoting Zhang

Doctoral Dissertations

Electrochemical epitaxy is a facile and inexpensive soft-solution process to fabricate highly ordered thin films. This research focuses on the epitaxial growth of metal-organic framework (MOF) thin films by electrochemical methods which include electro-conversion and electrodeposition.

First, an electrochemical conversion pathway was invented to achieve epitaxial MOF thin films. Epitaxial single-domain Cu-BTC(111) thin films were manufactured by electrochemical oxidation of Cu₂O(111) films electrodeposited on single-crystal Au(111). The single-crystal-like Cu-BTC(111) thin films with out-of-plane and in-plane order provide well-aligned 3.5 Å triangular windows along the [111] direction. Cu-BTC(111) foils were fabricated from the Cu-BTC/Cu₂O system by electrochemical …

Physical Properties Of Aqueous Imide-Based Electrolyte Solutions, Mollie Harr

Honors Capstones

In order to observe the effects that cations have on the physical properties of -TFSI [-bis(trifluoromethane sulfonyl)imide] based salts, four salts (LiTFSI, NaTFSI, Mg(TFSI)2, and Al(TFSI)3) were selected for testing. The data gathered shows that when the anion is large and bulky like -TFSI, the size of the cation does not have a large effect on the physical properties, but the oxidation state of the cation may have a significant effect. The ion-ion interactions, such as collisions, aggregation, and repulsion are more significant when the cation has a higher oxidation state due to the increased ratio of anion per molecule …

Novel, Ultra-Fast Electrochemical Sensors For The Enhanced Detection Of Neurotransmitters And Toxic Heavy Metals In Aqueous Solutions, Noel Manring

Theses and Dissertations

Neurodegenerative diseases (NDDs) are a growing global health concern, affecting millions of people worldwide. NDDs arise from the progressive loss of neuronal cell function, ultimately leading to cell death. Abnormal levels of neurotransmitters, the chemical messengers in the brain, have also been linked to NDDs. Despite various treatments and medications aimed at alleviating physical and mental symptoms, there is currently no cure or means to halt disease progression. While the exact pathogenesis of NDDs remain poorly understood, cognitive decline is largely attributed to brain volume reduction, particularly in the hippocampus. Clinical studies suggest that environmental factors, such as exposure to …

New Methods To Induce Selectivity In Electrochemical Reactions By Modifying The Electrode Surface, Enqi Feng

Arts & Sciences Graduate Student Theses and Dissertations

Organic electrochemistry has proven to be an efficient and green method for synthesis. Although the reactions studied to date have been very successful, there is still much to explore including opportunities to introduce new modes for controlling the selectivity of the reactions. Normally, the selectivity of an electrolysis reaction is based on the redox potential of the substrates. The working potential of an electrode either automatically adjusts to the potential required or is manually set at that potential. This allows for the systematic oxidation or reduction of a series of substrates that have a broad range of oxidation or reduction …

New Methods To Induce Selectivity In Electrochemical Reactions By Modifying The Electrode Surface, Enqi Feng

Arts & Sciences Graduate Student Theses and Dissertations

Organic electrochemistry has proven to be an efficient and green method for synthesis. Although the reactions studied to date have been very successful, there is still much to explore including opportunities to introduce new modes for controlling the selectivity of the reactions. Normally, the selectivity of an electrolysis reaction is based on the redox potential of the substrates. The working potential of an electrode either automatically adjusts to the potential required or is manually set at that potential. This allows for the systematic oxidation or reduction of a series of substrates that have a broad range of oxidation or reduction …

Electrochemistry At Work: Bouncing Batteries, Bryant Corbin, James Daniel, Jade Riddle

Fall Showcase for Research and Creative Inquiry

No abstract provided.

Design Of Engineered Nanomaterials For Pfas Adsorption And Catalytic Degradation From Relevant Environmental Conditions, Sheng Yin

Open Access Theses & Dissertations

Poly- and per-fluoroalkyl substances (PFAS) are a class of artificially made chemicals whose carbon chains are fully or partially fluorinated. Due to their persistent and pervasive distribution and their adverse effects on human health, the removal of PFAS from the environment has been the focus of current research. This project explores the use of engineered nanomaterials for the effective removal of PFAS through various adsorption and catalytic degradation methods. First, a comprehensive review of recent studies highlights the significant potential of various nanomaterials, including carbon-based, non-metal, single-metal, and multi-metal nanomaterials, for PFAS remediation. These materials are evaluated for their performance, …

Proton-Coupled Electron Transfer To Drive Biomass Conversion, Cody Canote

Graduate Theses and Dissertations

Meeting rising demands for commodity chemicals while simultaneously easing reliance on fossil fuels presents one of the most substantial challenges for chemistry to date. Biomass has emerged as a sustainable precursor to commodity chemicals but requires substantial deoxygenation to displace petrochemicals. Development of efficient catalysts to achieve these transformations remains one of the central goals of inorganic and organometallic chemistry. Electrochemical strategies to propel biomass conversion are attractive, providing the driving force for reactivity and insights into catalyst mechanism. This work focuses on proton-coupled electron transfer (PCET) to facilitate redox catalysis in biomass up conversion and homolytic bond cleavage in …

Electrochemical Detection Of Glucose Using A Prussian Blue Modified Electrodes Combined With Glucose Encapsulated Within A Xerogel, Daniel Baker, Sarah Davis, Drew Budner

Journal of the South Carolina Academy of Science

Recent literature reports examples of electrochemical biosensor systems that have been developed based upon on the encapsulation of enzymes and metal nanoparticles into a xerogel. These systems have been utilized for the detection of biologically important compounds, such as glucose. These reports on these systems have found acceptable detection limits and linear ranges. At the same time, Prussian blue modified electrodes have been shown to have better operating parameters than metal electrodes for the detection of hydrogen peroxide. In this work, a biosensor system is described that incorporates the encapsulation of glucose oxidize within a xerogel combined with electrochemical detection …

Comparison Of Ligands In Palladium-Catalyzed Electrochemical Allyl 4-Pyridinylation, Wei-Jie Ding, Chun-Hui Yang, Zhong-Tao Feng, Shi-Rong Lu, Xu Cheng

Journal of Electrochemistry

4-CN-pyridine is a widely applied 4-pyridinylation reagent for diverse transformations. Conventionally, the reaction proceeds via an open-shell radical cross-coupling pathway. Following our previous study, in this work, we report the Pd-catalyzed allyl 4-pyrinylation reaction under electrochemical conditions. The reaction proceeds via radical-polar crossover pathway in which the role of phosphine ligand in reactivity and selectivity was extensively investigated.

Recent Advance In Electrochemical Dehalogenative Deuteration, Peng-Fei Li, Guang-Sheng Kou, Li-Ping Qi, You-Ai Qiu

Journal of Electrochemistry

In recent years, the incorporation of deuterium atoms into organic compounds has emerged as a vital focus in the development of pharmaceutical molecules. This trend is driven by the increasing recognition of the significance of compounds containing deuterium atoms across various domains, including materials and biopharmaceuticals, where they have found widespread applications in mechanistic studies within the realms of chemistry and biology. Meanwhile, organic electrochemistry, as a relatively environmentally friendly catalytic mode with broad adaptability to redox reactions, has emerged as a crucial alternative to traditional halogen-deuterium exchange in the context of the reduction deuteration of halides. This approach circumvents …