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Ring-Opening And Monofunctionalization Study On Spiro Cyclic Aminals And N, O-Acetals System Via Nitrogen-Centered Radical Intermediates, Chujun Zhou

Graduate Theses and Dissertations

The nitrogen-centered radical has been drawing increasing attention among researchers. Radical polarity is one of the key factors in studying nitrogen-centered radicals’ reactivity, and the functional groups attached to the nitrogen atom are of vital importance. Among different types of nitrogen-centered radicals, aminium radical and metal aminium radical are electrophilic due to the positive charge on the intermediate. The sulfonamide radical, amidyl radical, and cyanide amine radical are also electrophilic since the nitrogen is adjacent to electron electron-withdrawing group. The neutral amino radical, iminyl radical, masked nitrogen radical are nucleophilic because of the electron-donating groups. After classifying the nitrogen-centered radical, …

Synthesis Of Phenyl-Substituted Zinc Dipyrrin Photosensitizer For Carbon Dioxide Reduction, Stephen Ankomah

Electronic Theses and Dissertations

The release of CO₂ from fossil fuel combustion drives the need for its conversion into more sustainable options like CO and CH₄ via photocatalytic reduction. This process requires a catalyst, sensitizer, and electron donor. Zinc dipyrrin-based complexes are promising photosensitizers, offering an alternative to expensive, rare-metal-based systems. Most first-row transition metal dipyrrin compounds have short excited-state lifetimes due to rapid nonradiative decay, but Zn(II) dipyrrin complexes stand out. With a d¹⁰ configuration, they lack deactivating ligand field states and can access long-lived triplet states through a charge-separated intermediate. A phenyl-substituted Zn(II) dipyrrin complex was synthesized and studied using NMR to …

Divergent Responses Of Branched-Chain And Straight-Chain Lipid Membranes To Butanol Stress Revealed By All-Atom Molecular Dynamics Simulations, Joshua Olaf Aggrey

Electronic Theses and Dissertations

Membrane integrity under chemical stress is critical to cellular survival and industrial microbial bioproduction, yet the molecular basis of bilayer resilience remains poorly understood. Using all-atom molecular dynamics simulation, we compare the effect of increasing concentrations of 1‑butanol on membranes composed of straight-chain (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC) and branched-chain (1-anteiso-palmitoyl-2-palmitoyl-sn-glycero-3-phosphocholine, APPC) lipids, which differ in the point of attachment of a single methyl group. In the absence of butanol, both membranes exhibit well-ordered architectures consistent with experimental benchmarks; however, under increasing solvent stress, their behaviors diverge markedly. DPPC membranes display gradual thinning, modest area per lipid …

Isolation, Chemical Characterization, And In-Vitro Cytotoxic Evaluation Of Novel Polar Flavonoids From Chromolaena Leivensis, Matthew Tohatsu Tetteh

Electronic Theses and Dissertations

This study focuses on isolation, chemical characterization, and in-vitro cytotoxic evaluation of novel polar flavonoids from chromolaena leivensis. A 95% ethanolic extract of c. leivensis shipped by Prof. Ruben Torrenegra from University of Applied and Environmental Sciences, Bogota, Colombia, was dissolved in 1:1 methanol/chloroform mixture and its purity analyzed by TLC. The sample was eluted with toluene/methanol in an increasing order of polarity on silica gel, resulting in 49 fractions labelled CLA1 to CLA49. Among these fractions, CLA10 (1) and CLA19 (2) obtained yellow and white crystals. They were analyzed by GCMS, IR, and …

Cosmetic Surgery And Physiological Disorder: You Should Talk To Someone About Your Unwinding Anxiety, Mona Muzammil, Washain Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Body dysmorphic disorder is a mental health condition in which you can't stop thinking about one or more perceived defects or flaws in your appearance — a flaw that appears minor or can't be seen by others. But you may feel so embarrassed, ashamed and anxious that you may avoid many social situations.

When you have body dysmorphic disorder, you intensely focus on your appearance and body image, repeatedly checking the mirror, grooming or seeking reassurance, sometimes for many hours each day. Your perceived flaw and the repetitive behaviors cause you significant distress and impact your ability to function in …

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 …

Regulating Lithium Metal Nucleation And Growth For Dendrite Suppression: From Liquid-Electrolyte To Solid-State Batteries, Ao Du, Juan Zhang, Pan Xu, Ya-Jie Li, Kang-Yu Yi, Zhen-Zhen Shen, Hui-Lin Ge, Guang-Wen Zhang, Chao-Hui Zhang, Yu-Hao Wang, Chen-Zi Zhao, Meng-Yang Xu, Yu-Lin Jie, Rui Wen, Shu-Hong Jiao, Si-Qi Shi, Qiang Zhang, Chun-Peng Yang, Yu-Guo Guo

Journal of Electrochemistry

Lithium metal anodes, with a theoretical capacity of up to 3860 mAh·g⁻¹, are regarded as the cornerstone for developing next-generation high-energy-density batteries. However, several key challenges hinder their practical applications, including dendrite formation, unstable solid electrolyte interphase (SEI), side reactions with electrolytes, and associated safety risks. This review systematically explores the mechanisms of lithium nucleation, growth, and stripping in both liquid and solid-state battery systems, analyzing critical theoretical concepts like heterogeneous nucleation thermodynamics, surface diffusion kinetics, space charge effects, and SEI-induced nucleation, which are crucial for understanding the genesis of dendrite growth. Additionally, the review discusses the electrochemical-mechanical …

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 …

Exploring Inorganic And Organometallic Chemistry, W. Christopher Boyd Phd

MSL Academic Endeavors eBooks

This textbook, Exploring Inorganic and Organometallic Chemistry, covers the fundamentals of inorganic and organometallic chemistry for undergraduate and graduate students. Both theories of structure and bonding and reaction chemistry are covered, with applications to the catalysis of organic reactions, biochemistry, and drug design. A modular approach allows for basic materials of each chapter to be covered in an undergraduate course, with more advanced material suitable for M.S. and Ph.D. students."

Novel Eco-Friendly Synthesis Of Coo Nps: Evaluation Of Their Diode Laser-Enhanced Inhibitory Activity Through Combined In Silico And In Vitro Approaches., Arshad Mahdi Hamad, Sahar Naji Rashid

Karbala International Journal of Modern Science

In our study, for the first time worldwide, to the best of our knowledge, cobalt oxide nanoparticles (CoO NPs) were synthesized using naringin (Nar) extracted from citrus peels. The properties of the prepared Nar-CoO NPs were studied using field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), ultraviolet-visible (UV-Vis), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. All the test results demonstrated the efficiency and success of the nanofabrication process. The solution was then exposed to three types of diode lasers: red (650 nm), green (532 nm), and blue (405 nm). The purpose of this study was …

Synergistic Doping And Coating Strategy For Boosting Na0.7mno2 Cathode Performance In Sodium-Ion Batteries, Ahmad Helaley, Han Yu, Manashi Nath, Xinhua Liang

Chemistry Faculty Research & Creative Works

Advancing sodium-ion battery (SIB) technology requires novel approaches to optimize cathode materials for improved electrochemical performance. In this study, we employ atomic layer deposition (ALD) to precisely modify the surface of P2-type Na_0.7MnO₂ cathodes with different coating materials including ZnO, NiO, and Al₂O₃, followed by post-annealing at 750°C for 10 hours. The strategic combination of ALD and thermal treatment can achieve thin film coating on particle surface and promote element doping into the near-surface lattice, as confirmed by electron energy loss spectroscopy (EELS) analysis. The incorporation of Zn, Al, and Ni results in …

Unraveling Hydration- And Temperature-Induced Structural Transformations Of Linear Poly(Ethylenimine) Using Raman Microscopy And Numerical Unmixing, Miharu Koh, Jay P. Kitt, Andrew D. Pendergast, Joel M. Harris, Shelley D. Minteer, Carol Korzeniewski

Chemistry Faculty Research & Creative Works

Linear poly(ethylenimine) (LPEI) is a hydration-sensitive polymer of interest for its breadth of application in areas that include medicine, energy, and materials science. To facilitate advances, this work demonstrates in situ Raman microscopy and self-modeling curve resolution (SMCR) analysis as an approach for investigating changes in LPEI structure during melting and crystallization under controlled heating and cooling conditions. With focus on neutral (freebase) LPEI, SMCR analysis of Raman data sets showed that the melting transition of anhydrous LPEI was well described by a pair of spectral vectors representing anhydrous crystalline and amorphous states. However, the transition from the melted to …

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 …

Direct Arylation Of 1,10-Phenanthroline Using An Organomagnesium Reagent, Nathanael A. Hirscher, Julian B. O. Van Esselstine, Bryan C. Yapo, Nadia Asif Masood, Erika L. Vandooijeweert

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Substituted derivatives of 1,10-phenanthroline are important ligands in inorganic chemistry. Such ligands are often synthesized by nucleophilic addition of aryl- or alkyllithium reagents to the carbon positions adjacent to the phenanthroline nitrogens. The typical reaction sequence (organolithium addition, protonolysis, oxidation, and rearomatization) has been widely used and seldom improved. We sought to replace lithium-based reagents with safer reagents based on magnesium (i.e., Grignards). The effective use of an arylmagnesium reagent in the production of a phenanthroline ligand derivative is now disclosed. Additionally, our newly reported method avoids the use of a heterogeneous oxidant (MnO2) which the traditional method employed in …

Sigma-Hole-Supported Interactions In Complexes Of Group 5 Oxyhalides (Mox3) With Insights For Their Extended Solids, Donovan Hoilette Jr., Gabriel F. Stewart, Kelling J. Donald

Chemistry Faculty Publications

The existence and nature of sigma hole type interactions in inorganic extended solids remain largely unexamined, even though the influence of such interactions for heteroorganic compounds is well known. The series of group 5 MOX₃oxyhalides are intriguing in this regard since several of the known crystal structures are molecular solids with highly polarized M centers. We examine computationally the bonding in the isolated MOX₃ molecules and their smallest clusters (MOX₃)_nwhere M = V, Nb, and Ta, and X = H, F, Cl, Br, and I. That investigation provides us with substantial evidence, based …

Postmortem Vitreous Humor As An Alternative Matrix To Peripheral Blood For Benzodiazepine Detection, Sara Bussey

Honors Theses

Benzodiazepines are commonly prescribed secondary drugs of abuse that cause Central Nervous System depression through the neurotransmitter gamma aminobutyric acid. While not commonly fatal on their own, benzodiazepines have a minor risk for physical dependence and abuse. They also can have cumulative effects with other medications that can lead to overdose situations; thus, they are considered secondary drugs of abuse. While peripheral blood is considered the standard for xenobiotic detection in postmortem forensic toxicology, it is important to consider the validity of alternative matrices that could be analyzed in the event that blood was not available due to circumstances like …

Synthesis And Characterization Of Eco-Engineered Hollow Fe2o3/Carbon Nanocomposite Spheres: Evaluating Structural, Optical, Antibacterial, And Lead Adsorption Properties, Islam Gomaa, Nikita Yushin, Mekki Bayachou, Vojislav Stani´, Inga Zinicovscaia

Chemistry Faculty Publications

This work presents a facile mechano-thermal route for the synthesis of carbon-decorated, hollow, mesoporous alpha-Fe2O3 microspheres. Comprehensive characterization (XRD, XPS, FT-IR, SEM/EDX, TGA, zeta-potential) confirmed the formation of phase-pure hematite with nanoscale crystallites (similar to 19 nm), substantial residual surface carbon (similar to 40 wt%) consistent with Fe-O-C linkages, and a positive surface charge (+15.9 mV). The hierarchical hollow/mesoporous architecture enables fast ion transport and provides extensive interior binding sites, resulting in rapid Pb(II) uptake that reaches 92% removal in approximate to 15 min at pH 5.0. The adsorption follows a Langmuir isotherm (q(max) approximate to 70.6 mg/g) and pseudo-second-order …

Multiplexed Integrin Detection And Cancer Cell Classification Using Multicolor Gap-Enhanced Gold Nanorods And Machine Learning Algorithm, Suprava Shah, Reed Youngerman, Alberto Luis Rodriguez-Nieves, Mitchell Lee Taylor, William Rodney Bantom, David Thompson, Jingyi Chen, Yongmei Wang, Xiaohua Huang

Chemistry & Biochemistry Faculty Publications and Presentations

Integrins, cell-surface adhesion receptors involved in tumor progression, invasion, and metastasis, serve as crucial biomarkers for cancer diagnosis and therapeutic targeting. Multiplexed detection of integrins and cancer cell classification at the single-cell level allows for comprehensive profiling, facilitating precise identification and categorization of tumor cells that are heterogeneous in integrin expression and cell subtype. In this study, we developed a five-plex detection platform and demonstrated integrin profile for cancer cell classification leveraging surface-enhanced Raman scattering (SERS) with gap-enhanced gold nanorods (GENRs) in conjunction with advanced computational analysis. Specifically, we synthesized GENRs bearing five distinct Raman nanotags, each producing a unique …

On Heat Engines Having Efficiencies That Degrade With Every Cycle That Are Nonetheless Reversible: The Wonders Of Hilbert Curves In The Pressure-Volume Plane, Daniel Graham

Chemistry: Faculty Publications and Other Works

Heat engines are cornerstones in classical thermodynamics, not to mention fixtures of everyday life. As everyone knows, real heat engines are rife with sources of irreversibility, and, in turn, have efficiencies that degrade over time. Here we chart a classical heat engine whose efficiency degrades with every cycle, but maintains perfect reversibility nonetheless. There are no paradoxes in play due to the inviolability of the thermodynamic laws. Rather the engine operates transparently according to Hilbert curves that fill the pressure-volume plane. The assembly of the curves is iterative and digital whereby no information is lost over every cycle.

Analysis Of An Effective Training Curriculum: Solutions Toincrease Participants' Interest In Training Teachingmaterials, Maulidya Husnul Khatimah, Yoto Yoto

Jurnal Pendidikan Sains

This research is important because it analyzes the curriculum as a primary tool for generating and maintaining participant interest. Curricula that are irrelevant, monotonous, or misaligned with participant needs are often the main causes of low motivation and participation. Furthermore, this research encourages the exploration and implementation of more innovative teaching methods and materials in training curricula. External pressure in the form of demands or instructions, rather than internal motivation, drives most training activities. This can reduce engagement and learning effectiveness. To overcome this, training institutions need to design programs that are relevant, flexible, and able to encourage participants' intrinsic …

Augmented Reality-Assisted E-Module On Temperature Andheat Content (Emarks), Tetri Sabrina, Ika Mustika Sari, Dedi Sasmita

Jurnal Pendidikan Sains

Temperature and heat content (calor) material in physics often involves concepts and phenomena that are difficult to observe directly or are abstract (such as energy transfer, particle movement, and changes in state). EMARKS (AR-based E-modules) are important because Augmented Reality (AR) allows the visualization of these abstract concepts in the form of interactive 3D models in the user's real environment. This helps students understand the concepts more concretely and easily. The development of E-modules is an innovation in learning media that is relevant to the demands of the digital era and the needs of modern students. The use of advanced …

The Effect Of Guided Inquiry Model With Deep Learningapproach On Student’S Hots In Elements, Compounds,And Mixtures At Junior High School, Friska Pakpahana, Retno Dwi Suyanti

Jurnal Pendidikan Sains

The current education curriculum places a strong emphasis on developing HOTS skills (such as analyzing, evaluating, and creating) to prepare students for the challenges of the 21st century. School learning often focuses on lower-level cognitive domains (memorizing and understanding). This research seeks to address this gap by offering a potentially effective learning model. The guided inquiry model positions students as active participants in learning, encouraging them to investigate, discover, and formulate concepts independently with teacher guidance. This strongly supports the development of critical thinking and problem-solving skills. Therefore, this study aims to analyze the effect of the guided inquiry model …

Development Of Problem-Based Learning Worksheet Toenhance Ecoliteracy: Human Impact On Ecosystem, Ulina M.S. Simangunsong, B. Manurung, Martina Asiati Napitupulu

Jurnal Pendidikan Sains

Ecoliteracy (ecological literacy) is an individual's ability to understand basic ecological principles and make environmentally responsible decisions. Improving ecoliteracy is a crucial foundation for realizing Education for Sustainable Development (ESD), which prepares students to become proactive citizens in protecting the environment. The problem-based learning model helps students learn on their own by using real-world environmental cases to get them to think critically and solve problems. Therefore, this research aims to determine the effectiveness of using problem-based learning worksheets to enhance the ecoliteracy of seventh-grade students. The development model used is 4-D. The research instruments include expert validation forms for subject, …

Development Of E-Lkpd Assisted By Phet Colorado Basedon Discovery Learning: Critical Thinking Skills On Lightmaterial At Junior High School, Flora Yani Saragih, Pintor Simamora

Jurnal Pendidikan Sains

Critical thinking is necessary for 21st-century pupils, but PISA data suggest that Indonesian students, especially junior high school students, lack it. The junior high science/physics light material is abstract and involves in-depth reasoning (reflection, refraction, and shadow generation). Without critical thinking, kids memorize formulas or notions without analyzing real phenomena. Discovery learning involves pupils discovering concepts via observation and experimentation. Critical thinking requires initiative, exploration, and reasoning, which these foster. Therefore, this study aims to develop E-LKPD based on Discovery Learning assisted by an interactive simulation of PhET Colorado to strengthen the critical thinking skills of grade VIII students on …

Guided Inquiry Learning Assisted By Crossword Puzzlemedia: Student Scientific Literacy And Critical Thinkingability For Middle School, Agis Putri Niswa, Mariati Purnama Simanjuntak, Ramlan Silaban, Fauziyah Harahap, Ridwan Abdullah Sani

Jurnal Pendidikan Sains

Scientific literacy and critical thinking skills are two fundamental competencies that students need in the 21st century. Scientific literacy is essential for students to understand and use scientific knowledge to make informed decisions, while critical thinking trains students to analyze information, evaluate arguments, and solve problems logically. Therefore, the intent of this study was to determine the effect of the guided inquiry learning model assisted by crossword puzzle media on students’ scientific literacy and critical thinking skills. The type of research used was quasi-experimental with a two-group pretest-posttest design. The sample consisted of two classes: class VII-8 as the control …

Elucidating The Effects Of Water Activity On The Hydration Kinetics And Thermodynamics Of Ye’Elimite–Calcium Sulfate Hydrate Systems, Godwin I. Ogbuehi, Rupack R. Halder, Aditya Kumar, Gaurav Sant, Monday U. Okoronkwo

Materials Science and Engineering Faculty Research & Creative Works

Relative humidity and water activity (aH) reductions have been known to suppress the hydration of anhydrous cement clinker phases. However, the relationship between ye'elimite (C4A3$) hydration kinetics and water activity remain unclear. This study employs experimental and thermodynamic modeling approaches to investigate the influence of water activity on ye'elimite hydration in the "C4A3$ + water", and "C4A3$ + gypsum + water" systems. Experimental findings indicate that as water activity decreases, C4A3$ hydration diminishes until the reaction is brought to a halt at a threshold aH. The critical aHand corresponding solubility constant of C4A3$ (KC4A3S¯) estimated from thermodynamic analysis are 0.46 …

Instructional Modality Matters: Predicting General Chemistry Ii Success From Online And In-Person General Chemistry I Experiences, Dave Mersing, Oluwatobi O. Odeleye

Excellence in Education: Teaching Faculty Symposium

We explore here whether the instructional modality of the first-semester General Chemistry I (GC1) course influences student learning outcomes in the subsequent General Chemistry II (GC2) course. This question has become increasingly important as institutions expand online and hybrid offerings for foundational science courses.

Importance Of S-Doped Porous Carbon Acidity And Visible Light Photoactivity For Its Antibacterial Activity, Danela Sadikaj, Abanob Fekri, Isabelle Bautista, Nafisatu Davis, Tasnim Agha Alkla, Muhammad Moueed Haider Mirza, Jiaying Wang, Phillip Stallworth, Natalie Hudson-Smith, Teresa J. Bandosz, Xiaojun Yu, Steven Greenbaum, Wanlu Li

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Bactericidal activity of sulfur-doped carbon has been investigated against a common Gram-negative bacterium, Escherichia coli K-12 (E. coli), in aqueous solution. Under dark conditions, 1 h contact of carbon with bacteria resulted in a 3–4 log decrease from the initial concentration of 7 log. When exposed to visible light, a 6–7 log decrease in E. coli was observed. The bactericidal activity under dark conditions was linked to the effects of functional groups, particularly sulfonic groups, which released protons that contributed to bacterial death. Even though under visible light no reactive oxygen species (ROS) were detected in electron paramagnetic …

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. …