Chemistry Commons^™

Advances In And Applications Of Capillary Scale Liquid Chromatography, Samuel William Foster

Theses and Dissertations

Analytical-scale high performance liquid chromatography (HPLC) is one of the most widely used analytical techniques in the world. Efforts have been made to reduce the mobile phase consumption of HPLC by reducing the inner diameter (I.D.) of the column. By using capillary-scale columns (< 0.5 mm I.D.), separations can be performed with orders of magnitude less solvent consumption. This work describes advances made to capillary scale instrumentation as well as applications enabled by these advances. A compact capillary-scale LC was used for the analysis of numerous pharmaceutical and illicit drug compounds for point of need analysis. A miniaturized mass spectrometer was coupled to this instrument for on-line reaction monitoring within a standard chemical fume hood. Kinetic profiles of commercially available capillary columns were developed in order to provide guidance to others during column selection. The implementation of a column oven improved the analysis of large biopharmaceuticals. Several critical quality attributes of monoclonal antibodies including fragmentation, charge variants, and glycosylation profiles were able to be determined on the capillary scale. These results will help to make capillary-scale liquid chromatography a more viable solution for chromatographic analysis.

Microwave-Assisted Synthesis And Surface Characterization Of Graphene Oxide-Antimony Trioxide Nanocomposites For Ascorbic Acid Electrochemical Sensor, Samir Mallick

Tennessee State University Alumni Theses and Dissertations

The detection and monitoring of Ascorbic Acid (AA) concentration is of crucial importance. Abnormal AA levels in bodily fluids have been reported to cause cancer, cardiovascular diseases, and Alzheimer’s and Parkinson’s diseases. Nanoparticles have played a critical role in developing affordable, sensitive, and selective sensors. This work reports on the electrochemical detection of AA using glassy carbon electrodes (GCEs) modified with microwave-assisted graphene oxide-antimony trioxide nanocomposite and chitosan films. The developed sensor displayed enhanced electron transfer and a better electrocatalytic reaction towards AA compared to other fabricated electrodes. Cyclic voltammetry and chronoamperometry were used for electrochemical measurements. CV and Fourier …

Enhancing Stability And Emissions In Metal Halide Perovskite Nanocrystals Through Mn2+ Doping, Thi Thu Trinh Phan, Thi Thuy Kieu Nguyen, Trung Kien Mac, Minh Tuan Trinh

Chemistry and Biochemistry Student Research

Metal halide perovskite (MHP) nanocrystals (NCs) offer great potential for high-efficiency optoelectronic devices; however, they suffer from structural softness and chemical instability. Doping MHP NCs can overcome this issue. In this work, we synthesize Mn-doped methylammonium lead bromide (MAPbBr₃) NCs using the ligand-assisted reprecipitation method and investigate their structural and optical stability. X-ray diffraction confirms Mn²⁺ substitution at Pb²⁺ sites and lattice contraction. Photoluminescence (PL) measurements show a blue shift, significant PL quantum yield enhancement, reaching 72% at 17% Mn²⁺ doping, and a 34% increase compared to undoped samples, attributed to effective defect passivation and …

The Influence Of Black Soldier Fly Residue On Watermelon Growth And The Properties Of A Coarse-Textured Ultisol, Benedict Onyebuchi Unagwu, Chidiebere Fransica Odu, Chinedu Felix Amuji, Michael Onyedika Eze, Nancy Ekene Ebido, Chidike Ude Abara, Chioma Rosita Igboka, Uchechukwu Paschal Chukwudi

Chemistry Faculty Research & Creative Works

Improving the fertility status of nutrient-depleted soils is critical to achieving food security. The negative effects of chemical fertilizers on soils necessitate the global quest for eco-friendly, effective, and sustainable alternatives. This work assessed the effect of black soldier fly (BSF) residue application on soil properties and watermelon growth. The study was set up in a completely randomized design with six replications. The treatments were BSF1 (BSF applied at 10 t ha⁻¹), BSF2 (20 t ha⁻¹), BSF3 (30 t ha⁻¹), and control. The plant data collected in this study were vine length, leaf width, …

Unveiling Exosomal Biomarkers In Neurodegenerative Diseases: Lc-Ms-Based Profiling, Yue Bi, Liang Wang, Chunyan Li, Zhiying Shan, Lanrong Bi

Michigan Tech Publications

Exosomes, small extracellular vesicles secreted by various cell types, play a critical role in intercellular communication and are increasingly recognized as key players in the progression of neurodegenerative diseases (NDs). Their ability to carry and propagate pathogenic proteins such as amyloid-beta, tau, and alpha-synuclein have established exosomal biomarkers as both key players in disease pathology and promising indicators for early diagnosis. Liquid chromatography-mass spectrometry (LC-MS) has emerged as a powerful tool for the comprehensive analysis of exosomal cargo, enabling the identification of proteins, metabolites, and other molecules associated with neurodegeneration. This review explores the structural composition, biogenesis, and role of …

Structural Color Pigments For Waterborne Coatings, Kyle William Liston

Master's Theses

Structural colors offer unique alternatives to conventional pigments, utilizing their microstructures to produce vibrant colors. These pigments offer an alternative source for colorants without the need for less environmentally friendly conventional pigments. In keeping with the sustainability approach, the use of waterborne coatings was chosen over solvent-based coatings. Here we report the synthesis of brushite platelet, silica supraball, and inverse opal pigments. Brushite platelets were produced through a condensation reaction, while silica supraballs were synthesized via the Stöber process and assembly was attempted using an oil-in-water emulsion. Inverse opal was produced through the templating of silica on poly(methyl methacrylate) (PMMA) …

Performance Evaluation Of Aminated Multi-Walled Carbon Nanotubes Incorporated With Green Synthesized Iron Nanoparticles For Toxic Dyes Sequestration From Textile Wastewater, Titus Chinedu Egbosiuba, Cynthia Chukwuemeka, Jonah Chukwudi Umeuzuegbu, Nwanneka Chibuzo Mmonwuba, Ugochukwu Ewuzie, Monday Uchenna Okoronkwo, Valentine Chikaodili Anadebe, Saheed Mustapha, Ambali Saka Abdulkareem, Jimoh Oladejo Tijani, Ashish Patel, Virendra Kumar Yadav

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study evaluates the performance of aminated multi-walled carbon nanotubes (AM-MWCNTs) integrated with zerovalent iron nanoparticles (ZVI) synthesized using cashew leaf (Anacardium occidentale) extract (AM-MWCNTs@ZVI) for the removal of Congo Red (CR) and Methylene Blue (MB) dyes from textile industrial wastewater. The nanocomposite was characterized using FTIR, XRD, BET, HRSEM, and HRTEM analyses, confirming its functional groups, crystalline structure, and enhanced surface area of 1050.4 m²/g. The ecological risk degree of the textile pollutants was assessed to determine the percentage concentrations of crystal violet, Congo red, methyl orange, methylene blue and rhodamine B. Batch adsorption experiments identified optimal …

Catalyzed Chemical Recycling Of Poly(Ethylene Terephthalate) For Enhanced Sustainability, Gilberto J. Hernandez-Leypon Jr.

Master's Theses

Plastics are ubiquitous in the production of consumer and industrial products; their chemical stability, low cost of production, and performance versatility make them the best option for many industries. Their inherent benefits, specifically durability, is the basis for the negative environmental impact of polymers. Improper containment of endof-life polymer products causes unintentional migration into the environment. The monomers for many common polymer types are also fossil fuel based further increasing the environmental impact of the plastic lifecycle. Recycling is a possible method of closing the loop of the plastic lifecycle. Currently most recycling is physical, thermally reprocessing used plastics into …

Comparing Machine Learning Paired Optimization Strategies For Single-Component Waterborne Direct-To-Metal Coatings, Harvir S. Kalkat

Master's Theses

As R&D attempts to fine tune properties before production, the redesign and testing process can become highly iterative. The repetitive nature of formulating can be difficult to escape when relying on chemical intuition alone. To provide some guidance in this process, machine learning (ML) can leverage data from previous trials¹ to design suggestions for subsequent trials. Although ML capabilities have vastly expanded in the last few years, integration of ML into chemistry R&D and education has been slow. Unraveling the mystique of ML can help change what has been a slow embrace in the coatings industry. It is important …

Early-Stage Detection Of Copper Ion Release From Bronze Corrosion Using Uv/Vis Spectroscopy And Hydrogel Sensing, Hibah Khan

University Honors Theses

Detecting copper(I) (Cu⁺) release at early corrosion stages is important for preserving bronze heritage materials. This study investigated the use of neocuproine (NC), a Cu⁺-specific ligand, for simple and selective colorimetric detection of Cu⁺ in solution. NC reacts with Cu⁺ to form a Cu(NC)₂ complex, which produces a distinct orange-red color with peak absorbance at 455 nm. Solutions were prepared with varying concentrations of Cu⁺ generated by reducing Cu²⁺ with excess ascorbic acid. Ultraviolet/Visible (UV/Vis) spectroscopy was used to quantify absorbance changes. The absorbance at 455 nm increased linearly across the tested Cu⁺ concentration range (6.25–200 µM) with an R² …

Characterizing Electrospray Performance Of Hydroxylammonium Nitrate (Han) And 2-Hydroxyethylhydrazinium Nitrate (Hehn) Ionic Liquids By Mass Spectrometry And Dynamics Simulations, Wenjing Zhou

Dissertations, Theses, and Capstone Projects

Dual-mode propulsion combines chemical and electric propulsion methods into a single compact system by sharing hardware and propellant for both modes, offering complementary advantages tailored to specific mission needs. A promising propellant candidate for dual-mode propulsion is a binary mixture of hydroxylammonium nitrate (HAN) and 2-hydroxyethylhydrazinium nitrate (HEHN) ionic liquids (ILs). Each of the two ILs was developed as a greener alternative to the traditional, yet toxic, hydrazine monopropellant used in chemical propulsion. Recently, their potentials in electrospray propulsion have garnered attention. This thesis focused on the investigation of reaction dynamics and kinetics of HAN, HEHN and their binary mixture …

Myceli-Yum: Elucidating Structure-Property Relationships For Polymer Degradation By Mycelial Digestion, Jordan Scott Ford

Master's Theses

Since the industrial entrance of polymer plastic materials, plastic has become ubiquitous in both everyday use and waste. Due to inefficiencies and knowledge gaps, current recycling methods are not able to account for the high scale of plastic waste, resulting in the bulk of this waste being landfilled, mishandled, and deposited in the environment. Mycelium, the microorganism responsible for fruiting mushroom bodies and mold growth, holds potential to reduce plastic waste and can potentially be utilized as a method of industrial recycling. Following a drug-design approach, the active site of mycelial enzymes responsible for natural biopolymer degradation have been assessed …

Probing Shielding Tensor Components Of Amino Acids Using Nuclear Magnetic Resonance, Shiva Agarwal

Dissertations

Chirality is fundamental to terrestrial life. While most amino acids exist as nonsuperimposable mirror images, amino acids in terrestrial life are homochiral, with the L-enantiomer being ubiquitous. The detection of an excess of L-amino acids in carbonaceous meteorites suggests that extraterrestrial processes may have contributed to this enantiomeric excess (ee). One proposed mechanism, the magnetochiral model, provides a potential explanation for this phenomenon in stellar environments characterized by strong magnetic and electric fields and the presence of relativistic leptons. According to this model, subtle differences in the electronic environments of chiral amino acids under such conditions …

An Inquiry Into The Physics Of Mixing And Floc Filtration, Andrew P. Pennock

Dissertations

Flocculation and clarification are two essential processes to deliver safe water at a reasonable cost to consumers. There are two major thrusts to the research presented in this dissertation. The first is to better characterize the physics and mixing parameters used for the design of hydraulic flocculators in the context of drinking water treatment plants. The second major thrust is to investigate floc filtration as a mechanism for the removal of primary particles during floc blanket clarification.

The intensity of mixing in environmental and chemical engineering applications is often characterized by the Camp and Stein velocity gradient. This parameter has …

Identifying Antimalarials That Disrupt Malaria Parasite Transmission When Fed To The Mosquito, Sarah N. Farrell, Anton Cozijnsen, Vanessa Mollard, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly, Geoffrey I. Mcfadden, Christopher D. Goodman

Chemistry Faculty Publications and Presentations

A decade-long decline in malaria cases has plateaued, primarily due to parasite drug resistance and mosquito resistance to insecticides used in bed nets and indoor residual spraying. Here, we explore the innovative control strategy targeting Plasmodium with antimalarials during the mosquito stages. This strategy has the potential to reduce the risk of resistance emerging because a relatively small population of parasites within the mosquito is subject to selection. After validating mosquito feeding strategies, we screened a range of parasiticidal compounds by feeding them to mosquitoes already infected with mouse malaria (P. berghei). Three antimalarials showed activity against P. berghei in …

Understanding The Morphology And Mass Transport Resistance Of Mesoporous Carbon-Supported Pemfc Based On Modeling Analysis, Hao Deng, Jia Liu, Zhong-Jun Hou

Journal of Electrochemistry

Mesoporous carbon supports mitigate Pt sulfonic poisoning through nanopore-confined Pt deposition, yet their morphological impacts on oxygen transport remain unclear. This study integrates carbon support morphology simulation with an enhanced agglomerate model to establish a mathematical framework elucidating pore evolution, Pt utilization, and oxygen transport in catalyst layers. Results demonstrate dominant local mass transport resistance governed by three factors: (1) active site density dictating oxygen flux; (2) ionomer film thickness defining shortest transport path; (3) ionomer-to-Pt surface area ratio modulating practical pathway length. At low ionomer-to-carbon (I/C) ratios, limited active sites elevate resistance (Factor 1 dominant). Higher I/C ratios improve …

Preparation And Modification Of Mxene Composites For Application In Electrochemical Energy Storage, Zhang-Hai You, Ding-Ze Lu, Kiran Kumar Kondamareddy, Wen-Ju Gu, Peng-Fei Cheng, Jing-Xuan Yang, Rui Zheng, Hong-Mei Wang

Journal of Electrochemistry

With the acceleration of advanced industrialization and urbanization, the environment is deteriorating rapidly, and non-renewable energy resources are depleted. The gradual advent of potential clean energy storage technologies is particularly urgent. Electrochemical energy storage technologies have been widely used in multiple fields, especially supercapacitors and rechargeable batteries, as vital elements of storing renewable energy. In recent years, two-dimensional material MXene has shown great potential in energy and multiple application fields thanks to its excellent electrical properties, large specific surface area, and tunability. Based on the layered materials of MXene, researchers have successfully achieved the dual functions of energy storage and …

Theoretical Insights Into The Atomic And Electronic Structures Of Polyperyleneimide: On The Origin Of Photocatalytic Oxygen Evolution Activity, Yi-Qing Wang, Zhi Lin, Ming-Tao Li, Shao-Hua Shen

Journal of Electrochemistry

Polymeric perylene diimide (PDI) has been evidenced as a good candidate for photocatalytic water oxidation, yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration. Herein, with crystal and atomic structures of the self-assembled PDI revealed from the X-ray diffraction pattern, the electronic structure is theoretically illustrated by the first-principles density functional theory calculations, suggesting the suitable band structure and the direct electronic transition for efficient photocatalytic oxygen evolution over PDI. It is confirmed that the carbonyl O atoms on the conjugation structure serve as the active sites for oxygen evolution reaction by the crystal …

Three-Dimensional Melamine Carbon Sponge/Nai As Cathode Materials For Sodium-Ion Batteries, Qian-Ying Huang, Yue Liu, Zi-Xin Lin, Shu-Yi Zheng, Ting-Ting Mei, Yu-Ting Tang, Ying-He Zhang, Jun Liu

Journal of Electrochemistry

The sodium-iodine (Na-I) battery exhibits significant potential as an alternative energy storage device to the lithium-ion battery. However, its development is hindered by inadequate electrical and thermal stability, as well as the dissolution and shuttling of polyiodide. In this study, we report a preparation method for melamine carbon sponge (MC) via carbonizing a commercially available kitchen sponge. It was revealed that the as-prepared MC, composed of unique self-growing carbon nanotubes, could provide both physical and chemical adsorption capabilities for intermediate polyiodides to improve the electrochemical performance of NaI. Consequently, the NaI/MC electrode effectively minimized polyiodide dissolution and reduced the electrochemical …

Optimization Of Renewable Energy Systems: Comparative Analysis Of Advanced Algorithms And Photovoltaic-Electrolyzer Performance For Cost Reduction And Efficiency Enhancement, Mohamed-Amine Babay, Mustapha Adar, Ahmed Chebak, Mustapha Mabroukia

Journal of Electrochemistry

The increasing demand for cost-effective and efficient renewable energy solutions presents significant optimization challenges in hybrid energy systems. This paper addresses these challenges by conducting a comparative analysis of three advanced optimization algorithms—Lévy Flight Optimization (LFO), Archimedean Optimization (AO), and Quantum Gorilla Optimization (QGO)—to minimize the Total Net Present Cost (TNPC) and Levelized Cost of Energy (LCOE) in hybrid renewable energy systems. The study integrates critical cost parameters such as Capital Expenditure (CAPEX), Operational Expenditure (OPEX), replacement costs, and salvage values into an advanced optimization framework. Three system configurations are evaluated: Wind Turbines and Fuel Cells (WT/FC), Photovoltaic Systems 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 …

The Nitrogen-Vacancy-Nitrogen Color Center: A Ubiquitous Visible And Near-Infrared-Ii Quantum Emitter In Nitrogen-Doped Diamond, Brett C. Johnson, Mitchell O. De Vries, Alexander J. Healey, Marco Capelli, Anjay Manian, Giannis Thalassinos, Amanda N. Abraham, Harini Hapuarachchi, Tingpeng Luo, Vadym N. Mochalin, Jan Jeske, Jared H. Cole, Salvy Russo

Chemistry Faculty Research & Creative Works

Photoluminescent defects in diamond, such as the nitrogen-vacancy (NV) color center, are at the forefront of emerging optical quantum technologies. Most emit in the visible and near-infrared spectral region below 1000 nm (NIR-I), limiting their applications in photonics, fiber communications, and biology. Here, we show that the nitrogen-vacancy-nitrogen (N2V) center, which emits in the visible and near-infrared-II (NIR-II, 1000-1700 nm), is ubiquitous in as-synthesized and processed nitrogen-doped diamond, ranging from bulk samples to nanoparticles. We demonstrate that N2V is also present in commercially available state-of-the-art NV diamond sensing chips made via chemical vapor deposition (CVD). In high-pressure high-temperature (HPHT) diamonds, …

Color Tests For The Presumptive Identification Of A Range Of Benzodiazepines, Regan Mulvin

Honors Projects

Color tests are presumptive chemical tests that determine the class of drug in both laboratory and field settings. Despite the rising popularity of benzodiazepines and the usefulness of color tests, there is no widely accepted color test for identifying them. This study tested six different color tests against five benzodiazepines, including diazepam, clonazepam, lorazepam, alprazolam, and flualprazolam, to identify which of the tests would work most generally across all benzodiazepines. Of the six tests, the McKibben test, the Janovsky test, and the Zimmerman test all showed potential usefulness as a presumptive color test. More studies should be done on a …

Nuclear Magnetic Resonance Dynamics Of Pyrazole-Litfsi Eutectic Solvents As Promising Electrolytes, Emilia Pelegano-Titmuss, Giselle De Araujo Lima E Souza, Muhammad Zulqarnain, Ramez Elgammal, Thomas Zawodzinski, Steven Greenbaum

Undergraduate Research

Deep Eutectic Solvents (DESs) have emerged as promising candidates to replace conventional organic solvents in various technological applications due to their low vapor pressure, non-flammability, and ease of preparation at low costs. In particular, Type IV DESs, which are composed of metal salts and hydrogen bond donors, are possible replacements for lithium-ion battery electrolytes due to their potential of having high lithium transference numbers. In this study, we investigated solvents of Pyrazole and LiTFSI at varying molar ratios using Fast Field Cycling (FFC) NMR Relaxometry. Notably, the 1:2 LiTFSI: Pyrazole sample shows distinct behavior, exhibiting enhanced relaxation rates for ^{1 …}

Characterization Of Sars-Cov-2 Replication And Transcription Complexes Via Structural And Evolutionary Approaches, Amelie Ghirardo, Ben Shabatian, Avishai Aghelian, Kyle Tau, Eleonora Gianti

Undergraduate Research

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused around 700M cases and over 7M COVID-19-related deaths recorded worldwide (World Health Organization, March 2025). Aiming to effectively combat this and other disease-causing Coronaviruses (CoV), unprecedented research efforts led to the development of new vaccines and antiviral therapies. Due to emergence of variants of concern (VOCs) with increased transmissibility, immune evasion from vaccination, and potential to resist the available treatments, SARS-CoV-2 continues to represent a major threat to global health. Hence, there is a pressing need to discover new antivirals with broad-spectrum efficacy against multiple SARS-CoV-2 variants and related CoVs. This project …

Transformer Decoder-Enhanced Swin Unetr For Multi-Organ Semantic Segmentation On Openkbp: Improving Radiotherapy Planning Accuracy, Zainab Adnan Jwad, Israa Hadi Ali

Karbala International Journal of Modern Science

Accurate segmentation of organs-at-risk (OARs) in head and neck CT scans is crucial for radiotherapy planning. The CNN-based decoder limitation of Swin UNETR hinders its capacity to process meaningful information from multiple organ positions essential for accurate medical segmentation. The proposed Transformer Decoder-enhanced Swin UNETR model targets the OpenKBP dataset multi-organ segmentation through its dedicated design for this purpose. The model utilizes transformers along with cross-attention approaches in its decoder to improve segmentation mask outputs through analysis of extensive global information. The model gets additional feature representation power through the addition of squeeze-and-excitation (SE) blocks linked with spatial attention mechanisms …

Computational Approach: 3d-Qsar, Molecular Docking, Molecular Dynamics Simulation Investigations, Drug- Like-Ness, And Dft Score Evaluation Of A Potential Novel And Retrosynthesis Of Some Tr-H Derivatives As Streptococcus Pneumoniae Drug., Belaidi Mustapha, Tchouar Noureddine, Djelilate Mohammed, Saleh Bufarwa, Dalal K. Thbayh

Karbala International Journal of Modern Science

Streptococcus pneumoniae is the main source of hospital-acquired pneumonia and meningococcal pneumonia in children, adults, and the elderly, especially the immunocompromised. Recently, it has attracted the attention of many research studies around the world as a potential target for remediation. TR-H are considered SP antibacterial agents, as they can inhibit. To describe their mode of action and to identify new antibacterial drugs against Streptococcus pneumoniae exhibiting the TR-H scaffold, the present work included 3D-QSAR, in- silico pharmacokinetic evaluation and molecular simulation modelling of TR-H. Using an atom-based method for quantitative structure-activity relationship (QSAR) study, a comprehensive 3D-QSAR model …

Conformational Change In A Four-Tetrad Dna G-Quadruplex Upon Intercalation Of A Small-Molecule Ligand Pydh2, Kailey N. Martin, Gwendolyn Lam , '24, O. Reznichenko, K. E. Brunner, M. J. Zdilla, Sawyer E. Mccarthy, Liliya A. Yatsunyk

Chemistry & Biochemistry Faculty Works

G-quadruplexes (G4s) are non-canonical DNA structures implicated in a number of biological processes. Small-molecule ligands can alter stability and folding of G4s, which can potentially be exploited for therapeutic purposes. In this work, we investigate the interaction of telomeric DNA fragment from Tetrahymena thermophila (TET25, 5′-G(TTGGGG)₄-3′) with a G4 ligand PyDH2 belonging to the bisquinolinium family. When alone, TET25 adopts a mixture of three conformations, with the most abundant being a four-tetrad hybrid G4. In the presence of PyDH2, surprisingly, TET25 folds into an antiparallel chair G4, with PyDH2 intercalated between G-tetrads 2 and 3, according to our crystal structure. …

Integrative Computational Modeling Of Distinct Binding Mechanisms For Broadly Neutralizing Antibodies Targeting Sars-Cov-2 Spike Omicron Variants: Balance Of Evolutionary And Dynamic Adaptability In Shaping Molecular Determinants Of Immune Escape, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this study, we conducted a comprehensive analysis of the interactions between the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein and four neutralizing antibodies—S309, S304, CYFN1006, and VIR-7229. Using integrative computational modeling that combined all-atom molecular dynamics (MD) simulations, mutational scanning, and MM-GBSA binding free energy calculations, we elucidated the structural, energetic, and dynamic determinants of antibody binding. Our findings reveal distinct dynamic binding mechanisms and evolutionary adaptation driving the broad neutralization effect of these antibodies. We show that S309 targets conserved residues near the ACE2 interface, leveraging synergistic van der Waals and electrostatic interactions, while S304 focuses on …

Application Of Quechers Extraction Method For Optimization Of Organic Matters In Oil Sand By Ultrahigh Fourier Transform Infrared Orbitrap-Mass Spectrometry, Gbenga Aladekoyi, Emmanuel G. Olumayede, Samuel O. Olusanya, Simeon Schum

Michigan Tech Publications

This work focuses on the performance of composite solvents using the QuEchERs extraction (quick, easy, cheap, effective, rugged, and safe) method in bitumen recovery and determination of organic matters present in the oil sands of the Okitipupa area of southwestern Nigeria. Different correlated parameters, such as extraction time (h), stirring time (r/ min), change in temperature (°C), and type of solvent (heptane—toluene and dichloromethane—toluene), solvent ratios (2: 8, 3: 7, 5: 5, 7: 3, and 8: 2) were used to optimize dissolved organic matters from the oil sands using QuEchERs extraction method. Ratios 1 g/2.5 ml for each solvent mix …