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Green Synthesis Of Carbonized Chitosan-Fe3o4-Sio2 Nano-Composite For Adsorption Of Heavy Metals From Aqueous Solutions, Dalia A. Ali Eng, Rinad Galal Ali Eng.

Chemical Engineering

Water pollution with heavy metals owing to industrial and agricultural activities have become a critical dilemma to humans, plants as well as the marine environment. Therefore, it is of great importance that the carcinogenic heavy metals present in wastewater to be eliminated through designing treatment technologies that can remove multiple pollutants. A novel green magnetic nano-composite called (Carbonized Chitosan-Fe3O4-SiO2) was synthesized using Co-precipitation method to adsorb a mixture of heavy metal ions included; cobalt (Co2+), nickel (Ni2+) and copper (Cu2+) ions from aqueous solutions. The novelty of this study was the synthesis of a new

nano-composite which was green with …

63rd Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 63rd annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in the Copper Conference Center, Copper Mountain, Colorado, August 4-8, 2024.

De Novo Synthetic Studies On Tetracyclic Triterpenoid Systems: Stereoselective Preparation, Biological Evaluation And Total Syntheses Of Euphol And Tirucallol, Joshua Nicholson

Dartmouth College Ph.D Dissertations

Tetracyclic triterpenoids have a rich history in biology, medicine, and chemistry. In terms of pharmaceutical relevance, compounds with this scaffold are one of the most successful classes with over 100 FDA approved examples. Despite this success, the vast majority of compounds within this class are prepared through semisynthesis. While this approach is undeniably successful, judged by the sheer number of medications generated, it also has limitations. Namely, semisynthesis requires the use of complex starting materials that have fixed absolute stereochemistry and often sparse functionality. One approach to address the inherent limitations with semisynthesis is through de novo synthesis. Recently, our …

Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Applications For Metabolomics, Darcy Cochran, Robert Powers

Robert Powers Publications

Metabolomics is an interdisciplinary field that aims to study all metabolites < 1500 Da that are ubiquitously found within all organisms. Metabolomics is experiencing exponential growth and commonly relies on high-resolution mass spectrometry (HRMS). Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) is a form of HRMS that is particularly well suited for metabolomics research due to its exceptionally high resolution (10⁵–10⁶) and sensitivity with a mass accuracy in parts per billion (ppb). In this regard, FT-ICR-MS can provide valuable insights into the metabolomics analysis of complex biological systems due to unique capabilities such as the easy separation of isobaric and isomeric species, isotopic fine structure analysis, spatial resolution of metabolites in cells and tissues, and a high confidence (error) in metabolite identification. Alternatively, the large and complex data sets, long acquisition times, high cost, and limited access mainly through national mass spectrometry facilities may impede the …

Knowledge Management Of Historical Data: Ontology Development For Chemical Reactions, Quynh D. Tran, Alexander Harding Bradley, Balashanmuga Priyan Rajamohan, Jonathan E. Gordon, Van D. Tran, Kiefer Lin, Erika I. Barcelos, Laura S. Bruckman, Roger H. French

Researchers, Instructors, & Staff Scholarship

Knowledge management of the literature and historical data is critical to accelerated drug and materials discovery. Currently, literature knowledge is scattered in journal articles in various formats: diagrams, texts, plots, etc. Historical data from past experiments are saved in a number of local computers under confusing folder structures with ambiguous file names. To manage and organize historical data and knowledge, our group (SDLE) at CWRU follows FAIR (Findable, Accessible, Interoperable, Reusable) principles, which outline the best practices for data stewardship and data provenance, and ontology, a formal representation of terms and concepts and their relationships, as a tool to improve …

Investigation Of The Prevalence Of Fentanyl Analogs In A Drug Testing Population Using Liquid Chromatography Tandem Mass Spectrometry (Lc-Ms-Ms), Ivan Cordova

Student Theses

This study serves to determine the prevalence of novel fentanyl analogs that are present within a drug testing population in New York State. Samples were analyzed using liquid chromatography tandem mass spectrometry (LC-MS/MS) to qualitatively determine the presence of various possible fentanyl analogs. The sample preparation of this assay consisted of a simple dilute and shoot. This method of sample preparation can be quicker, eliminating sample preparation times as well as being less financially strenuous to clinical laboratories as it eliminates the need for various solvents and solid/liquid phase cartridges. The assay was aimed to see if analytes can be …

I. Degradable Polymers And Networks Based On Furan-Maleimide Diels-Alder Reactions Of Silyl Ether Derivatives And Maleimides, And Ii. The Michael Addition Of Amines To 1,3,5-Triacryloylhexahydro-1,3,5-Triazine (Tat) As A Synthetic Route To Novel Chelating Agents, Reyad Alkhazalah

Chemistry Theses and Dissertations

Degradable Polymers and Networks Based on Furan-Maleimide Diels-Alder Reactions of Silyl Ether Derivatives and Maleimides. I.

I. Part 1. Two groups of silyl ether monomers, A and B, were synthesized, each containing four different monomers. The monomers of group A were obtained by reacting furfuryl alcohol with four dichlorosilanes with varying siloxane spacers. The monomers of group B were obtained by reacting n-(2-hydroxyethyl)maleimide (HEMI-1c) with the same four dichlorosilanes. Each monomer from group A was individually reacted with each monomer from group B via a Diels-Alder reaction to produce a series of sixteen degradable linear polymers with a variety …

Optimizing The Protein Yield Of The Collagen Mimetic Peptide: Col108, Fahmida Akter

Theses and Dissertations

Abstract

The fibril-forming collagen mimetic peptide Col108, produced in E. Coli, has shown potential for innovative biomaterial applications. However, further research is constrained by its limited yield. My study aims to enhance the experimental parameters and has successfully pinpointed rifampicin as an efficient method to boost the production of Col108.

Stimuli-Responsive Phosphate Hydrogel: A Study On Swelling Behavior, Mechanical Properties, And Application In Expansion Microscopy, Yokly Leng, Collin N. Britten, Fatema Tarannum, Kayla Foley, Christopher Billings, Yingtao Liu, Keisha B. Walters

Chemical Engineering Faculty Publications and Presentations

Phosphorus-based stimuli-responsive hydrogels have potential in a wide range of applications due to their ionizable phosphorus groups, biocompatibility, and tunable swelling capacity utilizing hydrogel design parameters and external stimuli. In this study, poly(2-methacryloyloxyethyl phosphate) (PMOEP) hydrogels were synthesized via aqueous activators regenerated by electron transfer atomic transfer radical polymerization using ascorbic acid as the reducing agent. Swelling and deswelling behaviors of PMOEP hydrogels were examined in different salt solutions, pH conditions, and temperatures. The degree of swelling in salt solutions followed CaCl₂ < MgCl₂ < KCl < NaCl with a decrease in swelling rate at higher concentrations until reaching a saturation point. In water, the degree of swelling increased significantly around neutral pH and remained constant at basic pH values. The effects of polymerization conditions, including pH, temperature (30, 40, 50 °C), and MOEP concentration (40, 50, 60% v/v MOEP/H₂O), on the hydrogel swelling behavior in various salt solutions were also investigated. PMOEP hydrogels …

High-Resolution Ion Mobility Analysis Of Isomeric Bile Acids Using Structures For Lossless Ion Manipulations (Slim) Im-Ms, Emmaleigh D. Efird

All Theses

Bile acids are an essential part of the human digestion system and play an important role in lipid absorption, bacteria movement in the small intestine, and regulation of the farnesoid X receptor (FXR) and G protein-coupled bile acid receptors (GPBAR) responsible for homeostasis. They are synthesized in the liver, stored in the gallbladder and the excess is carried on to the small intestine. Many liver and intestinal diseases are diagnosed based on bile acid metabolism pathways and the structures of those bile acids. Therefore, the bile acid structure determines the function of the molecule. Many bile acids are similar in …

Structure-Function Relationships In Neurodegenerative And Infectious Diseases: Biophysical Characterization Of Rna Secondary Structures By Computational Techniques, Kendy Guarinoni

Electronic Theses and Dissertations

The research described in this dissertation focuses on the investigation of the structure and dynamics of regions of RNA implicated in two diseases: COVID-19 and amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD). Both studies sought to create experimentally corroborated models that were used to characterize the structure and dynamics of the C9orf72 repeat expansion and the s2m region in coronaviruses, respectively and provided the foundation for future work. In our work involving the s2m region of SARS-CoV-2, the virus responsible for COVID-19, we determined that the homology modeling approach commonly used to derive atomistic structures when no coordinates are available yields a …

Investigating The Applications Of Peps To The Measurement Of The Stabilities Of Staphylococcal Nuclease (Stw) And Human Acidic Fibroblast Growth Factor (Hfgf1), Motolani Omolade Matthew

Graduate Theses and Dissertations

This dissertation presents a detailed investigation into the applications of Protein Equilibrium Population Snapshot H/D Exchange Electrospray Ionization Mass Spectrometry (PEPS-H/D exchange or PEPS) method. This method is based on protein equilibrium unfolding, and its fundamental capability is to capture a "snapshot" of the protein's state, allowing us to monitor the ratio of the unfolded to folded populations at different chemical denaturant concentrations. First, to increase the accuracy of PEPS data analysis for assessing protein stability, the traditional linear extrapolation method (LEM) was replaced. Instead of using LEM, which calculates free energy change based on the peak ratio of unfolded …

Development Of A Flow Cytometry Method For The Identification And Enumeration Of Enterococcus Faecalis, Riza Magbitang

Master's Theses

A multi-color flow cytometry method coupled with fluorescent staining was developed to detect and quantify E. faecalis concentrations in coastal waters as an alternative to the traditional membrane filtration method. The developed method was used to characterize E. faecalis during batch growth and yielded consistent results across the various physiological states of the cells. Additionally, the application of propidium iodide (i.e., a viability stain), afforded the method the ability to differentiate between cells with intact and compromised cell membranes, which raises the potential of quantifying cells that are in viable-but-non-culturable (VBNC) state. Initial field test using natural seawater samples spiked …

Single Charge Carrier Dynamics In A Single Polymer Chain, Ming Lei

All Dissertations

Understanding how charge carrier move through conjugated polymers is crucial for optimizing the functionality and efficiency of various applications, from organic solar cells and light-emitting diodes (LEDs) to field-effect transistors. Previous studies have demonstrated that tracking the fluorescence centroid displacement provides a method to determine the position of single charge carriers in a conjugated polymer nanoparticle. This method allows the observation of charge carrier trajectories over time and allow researchers to obtain insights into the dynamic processes. In addition, a detailed map of the energy landscape can be constructed by analyzing the fluorescence spectrum. These techniques were previously applied to …

Method Development For The Quantification Of Critically Valuable Elements In Permian Basin Produced Waters, Carley Oliver

Open Access Theses & Dissertations

Produced waters (PW) are a major byproduct of the oil and gas industrial hydraulic fracturing processes that create a major waste disposal issue with a need for disposal, treatment, and reuse method developments. The current primary disposal method is subsurface injection, which can lead to high pressures in the subsurface. PWs are often highly saline from mineral leaching due to long residence in subsurface reservoirs. According to the USGS National Minerals Information Center, bromine, calcium chloride, iodine, lithium, magnesium, and sodium chloride have been found in and extracted from these domestic subsurface brines, suggesting that there may be other economically …

Performance And Enhanced Efficiency Induced By Cold Plasma On Sapo-34 Membranes For Co2 And Ch4 Mixtures, Fnu Gorky, Vashanti Storr, Grace Jones, Apolo Nambo, Jacek B. Jasinski, Maria L. Carreon

Chemical Engineering Faculty Publications and Presentations

In this study, we investigate the influence of cold-plasma-induced enhanced performance and efficiency of SAPO-34 membranes in the separation of CO₂ and CH₄ mixtures. Placing the herein presented research in a broader context, we aim to address the question of whether cold plasma can significantly impact the membrane performance. We subjected SAPO-34 membranes to plasma mild disturbances and analyzed their performance in separating CO₂ and CH₄. Our findings reveal a notable enhancement in membrane efficiency and sustained performance when exposed to cold plasma. The pulsed plasma separation displayed improved structural integrity, and the experimental results …

Synthesis And Characterization Of Medicinally Privileged Aza Heterocycles, Nneoma James

Theses and Dissertations

Four-membered cyclic amides, commonly known as β-lactams, have played a crucial role in drug discovery research since its discovery by Alexander Fleming in 1928 from Penicillium notatum. The β-lactam antibiotics are broadly effective against several bacterial infections through acylating the transpeptidase involved in cross-linking peptides to form peptidoglycan or periplasmic murein, which is a fundamental constituent of the bacterial cell wall for both the gram-positive (ten or more layers) and gram-negative (one or two layers) bacteria. Although for more than eight decades, β-lactams have been recognized as antibiotics, later, other medicinal activities of β-lactam derivatives have been reported, including lowering …

Chemical Investigation Of The Ethanol Extract Of Tillandsia Usneoides (Spanish Moss), Jakir Hossain

Theses and Dissertations

Tillandsia usneoides in epiphytic bromeliads takes up water through absorptive trichomes on the shoot surface under extreme environmental conditions. Although previous studies revealed the way by which T. usneoides absorbs water and prevents water loss, its water transport remains unclear. Uses of T. usneoides L. have been documented going back to pre-Columbian and late archaic societies. Between the 1800s and 1900s. T. usneoides was utilized in fruit packing and polish, among other industrial goods. In terms of medicine, tillandsia is well-known for treating leucorrhea, rheumatism, ulcers, hemorrhoids, and as an anti-diabetic, emetic, analgesic, purgative, antispasmodic, and diuretic. The chemical composition …

Application Of Functionalized Organosilicas In Adsorption Of Nitrates, Stephen Amoako

Electronic Theses and Dissertations

This study addresses the critical environmental issue of elevated nitrate levels in water bodies, primarily due to excessive use of nitrogenous fertilizers and improper waste disposal. It focuses on reducing nitrate concentrations in polluted water to permissible levels through the effectiveness of hybrid materials in nitrate adsorption. We synthesized nine amino-functionalized adsorbents using grafting and sol-gel techniques. Batch adsorption tests confirmed the high nitrate adsorption capacities of these adsorbents, with sol-gel materials showing the highest efficiency due to their abundant amino group contents. Among these, the surfactant-free, sol-gel adsorbent was the most effective, combining ease of synthesis with cost-efficiency. Our …

Electrocatalytic Reduction Of Hydrogen Peroxide At Paraffin-Sealed Nitrogen-Doped Carbon Fiber Ultramicroelectrodes, Yakubu Gausu Mohammed

Electronic Theses and Dissertations

Compared to unmodified carbons and even some metal materials, nitrogen-doped carbons have been found to exhibit better performance for reducing oxygen-oxygen bonds, a key step in electroreduction of both O₂ (an important reaction in energy applications) and H₂O₂ (an important reaction in sensing and biosensing). Previous studies from our lab revealed that thermal decomposition of urea in the presence of carbon fiber (CF) results in N-doped that exhibited good electrocatalytic properties for H₂O₂ reduction. However, previous methods of sealing ultramicroelectrodes (UMEs) made from N-doped CF using laser heating of borosilicate capillaries and epoxy …

Effects Of Antifreeze Proteins On Lipid Membrane Stabilization At Cold Temperatures, Emily Vernon

Boise State University Theses and Dissertations

Cold-adapted organisms use antifreeze proteins (AFPs) and antifreeze glycoproteins (AFGPs) to enable survival in freezing habitats. AF(G)Ps have been proposed to prevent leakage of intracellular metabolites by stabilizing cellular membranes, a property that could be of great physiological and biomedical relevance. The generality of this effect is not understood, and for the known examples of membrane leakage prevention by AF(G)Ps, the mechanisms remain unclear. Here, we report a comprehensive evaluation of the effects of different AFPs on the leakage of ions and dyes from model membrane systems. We find that leakage is best prevented by AFGPs, while insect AFPs showed …

Differential Behavior Of Conformational Dynamics In Active And Inactive States Of Cannabinoid Receptor 1, Ugochi H. Isu, Adithya Polasa, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

Cannabinoid receptor 1 (CB1) is a G protein-coupled receptor that regulates critical physiological processes including pain, appetite, and cognition. Understanding the conformational dynamics of CB1 associated with transitions between inactive and active signaling states is imperative for developing targeted modulators. Using microsecond-level all-atom molecular dynamics simulations, we identified marked differences in the conformational ensembles of inactive and active CB1 in apo. The inactive state exhibited substantially increased structural heterogeneity and plasticity compared to the more rigidified active state in the absence of stabilizing ligands. Transmembrane helices TM3 and TM7 were identified as distinguishing factors modulating the state-dependent dynamics. TM7 …

Engineering Central Substitutions In Heptamethine Dyes For Improved Fluorophore Performance, Lei Guo, Meek Yang, Bin Dong, Seth Lewman, Alex Van Horn, Shang Jia

Chemistry & Biochemistry Faculty Publications and Presentations

As a major family of red-shifted fluorophores that operate beyond visible light, polymethine dyes are pivotal in light-based biological techniques. However, methods for tuning this kind of fluorophores by structural modification remain restricted to bottom-up synthesis and modification using coupling or nucleophilic substitutions. In this study, we introduce a two-step, late-stage functionalization process for heptamethine dyes. This process enables the substitution of the central chlorine atom in the commonly used 4′-chloro heptamethine scaffold with various aryl groups using aryllithium reagents. This method borrows the building block and designs from the xanthene dye community and offers a mild and convenient way …

Assessment Of Tce And Chiral Pcb Dechlorination Rate, Congener Diversity, And Enantioselectivity In Town Creek, Sc, Usa Sediment Microcosms, Catherine P. Sumner

All Dissertations

Polychlorinated biphenyls (PCBs) and trichloroethene (TCE) are ubiquitous contaminants and are recognized as persistent organic pollutants due to their extreme chemical stability. PCBs were manufactured by chlorinating biphenyls that created 209 congeners with various structures, of which 19 are chiral and can exist as a pair of stable atropisomers. PCBs have been known to cause developmental and neurological toxicity in humans and wildlife; they can act as endocrine disrupters, carcinogens, and teratogens. Sangamo Weston Inc. was an industrial plant located near Town Creek in Pickens Country, South Carolina, that manufactured capacitors and used Aroclors 1016 and 1254 as dialectic fluids …

Computational Models That Exploit Spatial, Temporal, And Voltage-Current Relationships In The Electrochemical Generation-Collection Of Redox-Active Molecules, Miguel Angel Abrego Tello

Graduate Theses and Dissertations

The numerical studies in this dissertation explore the application of redox cycling, an advanced electrochemical technique, for analyzing bioelectrochemical systems with a particular focus on small-volume samples and involves electrodes that can be activated to oxidize and reduce, separated by varying distances and featuring different geometries. The redox cycling approach facilitates the spatio-temporal interrogation of kinetics, mass transport, and the quantification and identification of chemical systems. We optimize a previously fabricated neural probe design on an SU-8 substrate, featuring coplanar arrays of nine microband electrodes suited for in vivo applications. Through comprehensive in situ and in silico redox cycling studies …

Use Of Computational Methods To Determine The Relative Thermodynamic Stability Of Myricetin, Quercetin And 4-Methylesculetin For Use As Spin Traps, Cole Walker

Electronic Theses and Dissertations

The research conducted focused on the oxidative intermediates of antioxidants known as Myricetin, Quercetin, and 4-Methylesutin by calculating the reaction mechanism. During this research, computational quantum chemistry on selected parts for the 3 antioxidants previously mentioned were performed to find the most stable intermediate to act as a spin trap. The hypothesis is that the intermediates found can act as spin traps which will allow longer preservation of a free radical to be identified using Electron Paramagnetic Resonance (EPR) spectroscopy. This may be because the buildup of excess free radicals in a system leads them to cause damage down to …

Assessing The Reactivity Of Amino Acids To Chlorination Using Capillary Electrophoresis, Pedro De Allende

Electronic Theses, Projects, and Dissertations

Amino acids (AA) are ubiquitous in wastewater systems. One of the most popular wastewater treatments is chlorination which is effective at eradicating bacteria and overall treating the wastewater, but it can also produce disinfection by-products (DBPs). Certain DBPs have been classified as Class B Carcinogens to humans and are therefore highly regulated and monitored. Past studies have shown that natural organic matter (NOM), specifically amino acids, can be precursors to DBPs if chlorinated to the correct dose. This thesis project explored AA chlorination's mechanism(s) to understand further which products arise. In particular, the investigation detailed which steps of the mechanism …

Evaluation Of Electrochemical Corrosion, Electrodeposition, And Other Electroanalytical Methods As Investigative Forensic Techniques For Advancing Metal Substrate Analysis, Crystal C. Kitanovski

UNLV Theses, Dissertations, Professional Papers, and Capstones

Friction ridge skin, bearing unique patterns of epidermal ridges commonly known as fingerprints, has served as a crucial tool for identification since ancient times, with its utilization dating back to Chinese culture around 221 B.C. Today, friction ridge skin impressions remain vital evidence in forensic investigations, aiding in the identification of suspects. While fingerprints, palm prints, and footprints can all serve as identifying markers, this dissertation focuses specifically on fingerprints, broadly classified as visible or latent. Latent fingerprints, though invisible to the naked eye, constitute the majority of prints collected from crime scenes, necessitating physical, chemical, or physicochemical processing for …

Metal Assisted O2-Dependent Carbon-Carbon Bond Cleavage Of Β-Diketones And Flavonols, Stephen N. Anderson

All Graduate Theses and Dissertations, Fall 2023 to Present

Almost everything we interact with on a daily basis has been synthesized by chemists ranging from plastics, food preservatives, and medications. The diversity of synthetic molecules are achieved by the formation of new bonds between existing molecules and/or through the cleaving of bonds found in a molecule. There are uncountable amount of conditions reported to facilitate chemical reactions which all depend on the nature of molecules being used and the environment it is used in.

In recent years, more attention has been paid to identify chemical reactions that can use more environmentally favorable conditions and reduce the use of limited …

Characterizing Gsk3Β Interaction And Kinetics Via Isothermal Titration Calorimetry, W A Bhagya De Silva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Glycogen synthase kinase 3β (GSK3β) is a multifunctional serine/threonine kinase involved in several key signaling pathways, including glycogen metabolism, WNT/β-catenin, and Hedgehog signaling. Hyperactivity of GSK3β has been linked to Alzheimer’s disease, bipolar disorder, type II diabetes, and some cancers. Therefore, GSK3β is of interest as a target for therapeutics. Lithium ion (Li+) is a classical inhibitor of GSK3β. Structurally similar beryllium ion (Be2+) is ~1000-fold more potent. Lithium and beryllium have demonstrated pathway-specific and cell type-specific inhibition of GSK3β, prompting an investigation into the inhibitory mechanisms and thermodynamic characteristics of the metal-enzyme interaction.Isothermal titration calorimetry (ITC) is a label-free …