Chemistry Commons^™

Electrospun Ethyl Cellulose Nanofibers With Phase Change Materials: Designing Temperature-Responsive Drug Delivery Systems, Michael Wildy

Theses and Dissertations

In this study, ethyl cellulose (EC) nanofibers loaded with either Rhodamine B (RhB) or Doxorubicin HCl (DOX) and phase change materials (PCM) were fabricated by blend electrospinning. EC is a cellulose derivative widely used as an excipient in the pharmaceutical industry and an ideal polymer for controlled drug release. Lauric acid (LA) and stearic acid (SA) were used as a material with a melting point close to physiological body temperature. Good drug-polymer compatibility and an amorphous distribution of drugs were shown by Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction. The release rate of RhB was shown to …

Fluorescent Molecular Rotors As Versatile In Situ Sensors For Protein Quantitation, Kevin Daus, Sorachat Tharamak, Wanchai Pluempanupat, Peter Galie, Maria A Theodoraki, Emmanuel A Theodorakis, Mary Alpaugh

College of Science & Mathematics Departmental Research

Accurate protein quantitation is essential for many cellular mechanistic studies. Existing technology relies on extrinsic sample evaluation that requires significant volumes of sample as well as addition of assay-specific reagents and importantly, is a terminal analysis. This study exploits the unique chemical features of a fluorescent molecular rotor that fluctuates between twisted-to-untwisted states, with a subsequent intensity increase in fluorescence depending on environmental conditions (e.g., viscosity). Here we report the development of a rapid, sensitive in situ protein quantitation method using ARCAM-1, a representative fluorescent molecular rotor that can be employed in both non-terminal and terminal assays.

Investigation Of Electron Transfer In The Ksha-Kshb-R286a Protein Complex From Mycobacterium Tuberculosis, Elyse Tavares

Honors Program Theses and Projects

With drug-resistant bacteria such as Mycobacterium tuberculosis being a serious public health problem, infected individuals have minimal treatment options. By investigating the electron transfer within 3-ketosteroid-9��-hydroxylase (KshAB), a protein involved in the energy production pathway of this bacteria, it will allow for potential inhibitors of this enzyme to be designed as antibiotics against tuberculosis. The purpose of this project is to stop the interaction between the KshA and KshB complexes to prevent the bacteria from gaining energy by breaking down steroids like cholesterol. To achieve this goal, an arginine at the 286th position of the KshB protein was mutated to …

Methods For Analytical And Biophysical Analysis For Investigation Of Stimulator Of Interferon Genes In Drug Discovery, William Emmett Brian Lawless

USF Tampa Graduate Theses and Dissertations

This work elaborates on analytical and biophysical techniques including high pressure liquid chromatography (HPLC), mass spectrometry quadrupole time-of-flight (MS-QToF), dynamic light scattering (DLS), microscale thermophoresis (MST), surface plasmon resonance (SPR), isothermal calorimetry (ITC), size exclusion chromatography, and native gel electrophoresis. A basic overview is described for each technique and is designed for easy understanding by both novice and experienced analysts. Best practices for each technique are discussed and suggestions are made for protocol improvements or troubleshooting. Protocol development is discussed, and a method is introduced for MST that can be adapted to any target protein for rapid screening of analog …

New Methods For Stereoselective Glycosylation In Application To Significant Biomedical Targets, Melanie L. Shadrick

Dissertations

Glycosyl halides have been utilized for glycosylation reactions since the early studies by Arthur Michael, nearing the end of the 19^th century. Koenigs and Knorr then utilized silver salts to activate glycosyl bromides and chlorides to create synthetic glycosides. Many efforts to improve the outcome of reactions with glycosyl halides have emerged. The key emphasis has traditionally been placed on reaction rates, product yields, and stereocontrol. Recently, our lab reported that silver(I) oxide-mediated Koenigs-Knorr glycosylation reaction can be dramatically accelerated in the presence of catalytic acid additives. Methods to improve glycosylation was explored using mannosyl and glucosyl bromides. However, …

Investigating The Diffusion Of Solid Yttria Into Solid Zirconia For The Formation Of Yttria Stabilized Zirconia, Logan Thomas Ockershausen

Seton Hall University Dissertations and Theses (ETDs)

A molecular dynamics simulation of yttria-stabilized zirconia (YSZ) is reported in order to analyze the diffusion of the oxygen atoms from the yttria into the zirconia from an initial structure containing a layer of yttria on zirconia. The simulation was performed starting from a pure zirconia slab which was amorphized at the surface followed by placing a slab of yttria on top and a vacuum layer above that. The yttria/zirconia system was simulated at increasing temperatures to 1500K under canonical (NVT) constraints for 6.98 ns until the yttrium atom diffusion was found to occur. The final run was analyzed for …

Sigma Hole Potentials As Tools: Quantifying And Partitioning Substituent Effects, Kelling J. Donald, Nam Pham, Pranav Ravichandran

Chemistry Faculty Publications

Empirical substituent constants such as the Hammett parameters have found important utility in organic and other areas of chemistry. They are useful both in predicting the impact of substitutions on chemical processes and in rationalizing, after the fact, observations on chemical bonding and reactivity. We assess the impact of substitutions on mono-iodinated benzene rings and find that the modifications that substituents induce on the electrostatic potentials at the sigma hole on the terminal I center correlate strongly with established trends of common substituents. As an alternative to the experimental procedures involved in obtaining empirically based substituent constants, the computationally determined …

Cognitive Engagement During Group Learning Activities In Chemistry Courses: An Analysis Of Student Discourse, Safaa Youssef El-Mansy

Dissertations and Theses

As educators, our goal is to help our students be successful, but in order to accomplish this, we need to understand what factors contribute to student success. One factor, small-group active learning, has been correlated to improved academic outcomes; however, the magnitude of this improvement can vary across different courses, different types of group work, and even across courses that use the same group work structure. Therefore, it is important to understand what aspects of group work contribute to its effectiveness. The work presented in this dissertation investigated one specific aspect: students’ cognitive engagement. This was done by analyzing the …

Exclusive Regioselective Synthesis Of Potentially Bioactive 1,3,4-Selenadiazole, Mohamed Ali Mahmoud

Thesis/ Dissertation Defenses

Isoselenocyanates have a crucial role as reactants in chemical processes, facilitating the efficient synthesis of significant chemical intermediates and physiologically active chemicals. The utilization of (Z)-2-oxo-N-phenylpropanehydrazonoyl chlorides in a one-step procedure for the synthesis of the core structure of various heterocyclic compounds has been widely explored. This study focuses on the synthesis of 5-arylimino-1,3,4-selenadiazole derivatives through the reaction of isoselenocyanates with various substituted (Z)-2-oxo-N-phenylpropanehydrazonoyl chlorides. The objective is to achieve selective and accurate formation of these derivatives. The derivatives exhibit a diverse range of functional groups on both aryl rings. The synthetic procedure is conducted under ambient conditions, promoting environmental …

Impacts Of Hydrophobic Mismatch On Antimicrobial Peptide Efficacy And Bilayer Permeabilization., Steven Meier, Zachary M Ridgway, Angela L Picciano, Gregory A. Caputo

College of Science & Mathematics Departmental Research

Antimicrobial resistance continues to be a major threat to world health, with the continued emergence of resistant bacterial strains. Antimicrobial peptides have emerged as an attractive option for the development of novel antimicrobial compounds in part due to their ubiquity in nature and the general lack of resistance development to this class of molecules. In this work, we analyzed the antimicrobial peptide C18G and several truncated forms for efficacy and the underlying mechanistic effects of the sequence truncation. The peptides were screened for antimicrobial efficacy against several standard laboratory strains, and further analyzed using fluorescence spectroscopy to evaluate binding to …

Binding Interactions Of Biologically Relevant Molecules Studied Using Surface-Modified And Nanostructured Surfaces, Palak Sondhi

Dissertations

This research focuses on the field of surface nanobioscience, wherein different nanosurfaces that will be used as working electrodes in the electrochemical cell are manufactured and surface modified to understand the critical binding interactions between biologically significant molecules like proteins, carbohydrates, small drug molecules, and glycoproteins. This research is essential if we are to determine whether a synthetic molecule can serve as a therapeutic candidate or diagnose a disease in its early stages. In order to fully understand the binding interactions, the study begins with defining some of the fundamental concepts, principles, and analytical tools for biosensing.

Afterwards, we addressed …

Functional Aggregation Of Cell-Free Proteins Enables Fungal Ice Nucleation, Ralph Schwidetzky, Ingrid De Almeida Ribeiro, Nadine Bothen, Anna T. Backes, Arthur L. Devries, Mischa Bonn, Janine Fröhlich-Nowoisky, Valeria Molinero, Konrad Meister

Chemistry and Biochemistry Faculty Publications and Presentations

Biological ice nucleation plays a key role in the survival of cold-adapted organisms. Several species of bacteria, fungi, and insects produce ice nucleators (INs) that enable ice formation at temperatures above −10 °C. Bacteria and fungi produce particularly potent INs that can promote water crystallization above −5 °C. Bacterial INs consist of extended protein units that aggregate to achieve superior functionality. Despite decades of research, the nature and identity of fungal INs remain elusive. Here, we combine ice nucleation measurements, physicochemical characterization, numerical modeling, and nucleation theory to shed light on the size and nature of the INs from the …

Evaluation Of Iron Element By New Cpe Method And (Icp-Ms) In The Wastewater Of The Lifting And Treatment Stations, Mohammed Nasser Hussain, Ahmed Fadhil Khudhair, Hussain Jawad Ahmed

Al-Bahir

A new micell-mediated phase separation technique has been created to preconcentrate levels of iron before measuring it using a UV-Vis spectrophotometer. The method is based on the extraction of iron from the 1-Nitroso-2- naphthol reagent using Triton X-114 in a cloud point extraction procedure, where the method's ideal conditions were attained. 0.2 mL of Triton X-114, 2.887 mmol. L-1 of 1-Nitroso-2-naphthol reagent, pH = 8, 60 ºC. The Iron detection limit for the method is 0.05 µg. mL-1, and the RSD% is 4.728 µg. mL-1. Linearity was maintained in the iron concentration range of 0.25 to 16 µg. mL-1. Furthermore, …

Development Of Antibacterial Neural Stimulation Electrodes Via Hierarchical Surface Restructuring And Atomic Layer Deposition., Henna Khosla, Wesley Seche, Daniel Ammerman, Sahar Elyahoodayan, Gregory A. Caputo, Jeffrey Hettinger, Shahram Amini, Gang Feng

College of Science & Mathematics Departmental Research

Miniaturization and electrochemical performance enhancement of electrodes and microelectrode arrays in emerging long-term implantable neural stimulation devices improves specificity, functionality, and performance of these devices. However, surgical site and post-implantation infections are amongst the most devastating complications after surgical procedures and implantations. Additionally, with the increased use of antibiotics, the threat of antibiotic resistance is significant and is increasingly being recognized as a global problem. Therefore, the need for alternative strategies to eliminate post-implantation infections and reduce antibiotic use has led to the development of medical devices with antibacterial properties. In this work, we report on the development of electrochemically …

Inhibition Of Chromium(Iii) Oxidation Through Manganese(Iv) Oxide Passivation And Iron(Ii) Abiotic Reduction, Miranda L. Aiken, Macon J. Abernathy, Michael V. Schaefer, Ilkeun Lee, Samantha C. Ying

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Manganese (Mn) oxides are strong oxidants that are ubiquitous in soils and can oxidize redox-active metals, including chromium (Cr). In soil environments, trivalent chromium (Cr(III)) is a benign, immobile micronutrient, whereas the hexavalent Cr(VI) form is present as a highly mobile, toxic chromate oxyanion. Although many studies have characterized the capacity of Mn(III/IV) oxides to oxidize Cr(III) to toxic Cr(VI), the oxidative capacity of Mn oxides in the presence of potentially passivating soil constituents, specifically reduced soluble iron (Fe(II)aq), remains unresolved. We hypothesized that chemical processes at redox interfaces, such as diffusion-limited environments within soil aggregates, can lead to decreased …

Bioelectrocatalytic Synthesis: Concepts And Applications, Dylan G. Boucher, Emily Carroll, Zachary A. Nguyen, Rohit G. Jadhav, Olja Simoska, Kevin Beaver, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Bio electrocatalytic synthesis is the conversion of electrical energy into value-added products using biocatalysts. These methods merge the specificity and selectivity of biocatalysis and energy-related electrocatalysis to address challenges in the sustainable synthesis of pharmaceuticals, commodity chemicals, fuels, feedstocks and fertilizers. However, the specialized experimental setups and domain knowledge for bio electrocatalysis pose a significant barrier to adoption. This review introduces key concepts of bioelectrosynthetic systems. We provide a tutorial on the methods of biocatalyst utilization, the setup of bioelectrosynthetic cells, and the analytical methods for assessing bio electrocatalysts. Key applications of bio electrosynthesis in ammonia production and small-molecule synthesis …

Youth In Danger And Students At Risk Of Dropping Out, Mamoona Muzammil, Muzammil Arshad

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

Bullying is any unwanted aggressive behavior(s) by another youth or group of youth that involves an observed or perceived power imbalance and is repeated multiple times or is highly likely to be repeated. Bullying may inflict harm or distress on the targeted youth including physical, psychological, social, or educational harm. Bullying can lead to fear of school, absenteeism, and stunted academic progress, which in turn are precursors to dropping out of school.

• Effects of Bullying on Students Long lasting effects
• School Dropout.
• Lack of Concentration
• Reduced Motivation
• Less Class Participation
• Less Attendance Lower Academic Achievement

Student Dropouts

The increase in …

Cost Analysis Of Adsorption Based Air Capture Of Co2, Mona Muzammil, Muzammil Arshad, Muazzam Arshad

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

Carbon dioxide (CO2) capture and conversion to value added products, such as chemicals, polymers, and carbon-based fuels represents a promising approach to transform a potential threat to the environment into a value-added product for long term sustainability. Emerging Carbon Capture Technologies: Towards a Sustainable Future provides a multidisciplinary view of the research that is being carried out in this field, covering materials and processes for CO2 capture and utilization and including a broad discussion of the impact of novel technologies in carbon capture on the energy landscape, society and climate. Of interest to students, researchers and professionals in industries related …

Electrochemical Degradation Of Methylene Blue With Seawater And Pb/Pbo2 Electrodes From Battery Waste, Gunawan Gunawan, N. B. Adiwibawa Prasetya, Didik Setiyo Widodo, Roni Adi Wijaya

Karbala International Journal of Modern Science

Electrochemical degradation of methylene blue (MB) dye with seawater electrolyte using lead and lead oxide (Pb/PbO2) electrodes from waste batteries has been successfully conducted. Characterization of battery waste, the effectiveness of dye degradation, sodium hypochlorite (NaOCl) concentration, dissolved oxygen (DO) level, reaction mechanism, the effect of time variation (15, 30, 45, and 60 minutes), and voltage variation (0, 1, 2, 3, 4, and 5 volts) were observed. Characterization showed results by the characteristics of Pb and PbO2 confirmed by X-ray diffractometer (XRD) result-ing in 2θ peaks of Pb at 31.36, 36.38, 52.26, 62.36, 65.38º and 2θ (β-PbO2) at 25.4, 32.0, …

Biochemical Characterization Of A Fructosyltransferase Enzyme From A Halophilic Archaeon, Haloarcula Marismotui, For Biotechnological Applications, Ahlam Khalifa Al Ameri

Thesis/ Dissertation Defenses

Fructosyltransferase enzymes are involved in the production of fructans, which are polymers of fructose and naturally present in many foods like fruits, vegetables, legumes, and cereals. Fructans with short chain lengths are called Fructooligosaccharides (FOS), which are small dietary fibers having low caloric values and are known as “prebiotics”. Fructans have a broad range of applications in the food, pharmaceutical, cosmetics, and chemical industries. They have unique physicochemical properties and functionalities depending on the source of enzyme used for their production. The present study aimed at the utilization of a recently discovered unique fructosyltransferase enzyme from an extremely halophilic microorganism, …

Relation Between Halogen Bond Strength And Ir And Nmr Spectroscopic Markers, Akhtam Amonov, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The relationship between the strength of a halogen bond (XB) and various IR and NMR spectroscopic quantities is assessed through DFT calculations. Three different Lewis acids place a Br or I atom on a phenyl ring; each is paired with a collection of N and O bases of varying electron donor power. The weakest of the XBs display a C–X bond contraction coupled with a blue shift in the associated frequency, whereas the reverse trends occur for the stronger bonds. The best correlations with the XB interaction energy are observed with the NMR shielding of the C atom directly bonded …

A Computational Approach For Mapping Electrochemical Activity Of Multi-Principal Element Alloys, Jodie A. Yuwono, Xinyu Li, Tyler D. Dolezal, Adib J. Samin, Javen Qinfeng Shi, Zhipeng Li, Nick Birbilis

Faculty Publications

Multi principal element alloys (MPEAs) comprise an atypical class of metal alloys. MPEAs have been demonstrated to possess several exceptional properties, including, as most relevant to the present study a high corrosion resistance. In the context of MPEA design, the vast number of potential alloying elements and the staggering number of elemental combinations favours a computational alloy design approach. In order to computationally assess the prospective corrosion performance of MPEA, an approach was developed in this study. A density functional theory (DFT) – based Monte Carlo method was used for the development of MPEA ‘structure’; with the AlCrTiV alloy used …

In Silico And In Vitro Drug Discovery Strategies And The Chemical Investigation Of Endophytic Fungi, Sarah Grace Dietrick

USF Tampa Graduate Theses and Dissertations

The biodiversity of our global marine ecosystems provides substantial treasure to discover: chemistry. Marine organisms that live in proximity to one another use their unique chemistry to compete with one another and thrive in their environment. Benthic invertebrates, specifically, that lack physical means of protection will produce secondary metabolites as a means of defense from their surroundings and predators. The compounds which they produce are ordinarily species-specific, highly diverse biomolecules. Biosynthetic processes within an organism construct these secondary metabolites from fragments of primary metabolites (amino acids, fatty acids, sugars, and so on). Their roles in protection have antibiotic, toxic, and …

Syntheses, Photophysics, & Application Of Porphyrinic Metal-Organic Frameworks, Zachary L. Magnuson

USF Tampa Graduate Theses and Dissertations

Porphyrins are a group of heterocyclic macrocycles that play crucial roles in various biological processes such as electron transfer, catalysis, and sensing. Hemoglobin, which carries oxygen in the blood of mammals, and chlorophyll, which drives photosynthesis in plants and algae, are both porphyrins. The ability of porphyrins to bind metal ions and their unique electronic and photophysical properties make them an excellent platform for designing functional materials for various applications, often drawing inspiration from their function in nature. Metal-organic frameworks (MOFs) are a class of porous materials that have been extensively studied in recent years due to their high surface …

Synthetic Studies Of Potential New Ketogenic Molecules, Mohammad Nazmus Sakib

USF Tampa Graduate Theses and Dissertations

The ketogenic diet has gained popularity in the past few decades among people and physicians due to its various health benefits. A significant amount of research has been done for the modification of the original ketogenic diet and investigation of its potential health benefits. However, synthesis of novel ketogenic compounds as a dietary supplement has not received the same level of attention. That is the primary objective of this research project. The first chapter of this manuscript describes the synthesis of various short and medium chain esters of different polyols that have been done so far, and areas of their …

Modification Of Cellulose Fibers By Acyl Grafting For Oil Spill Remediation, Fatima Saif Alhumaidi

Thesis/ Dissertation Defenses

Oil spills represent a significant source of aquatic pollution with substantial repercussions on the environment as well as the economic and societal well-being of coastal communities. This research project is focused on the utilization of chemically modified cellulose-based fibers to remediate oilcontaminated water. The hydroxyl groups present in cellulose were acetylated under optimized conditions, thereby rendering the fibers hydrophobic and enhancing their affinity for crude oil. The modified cellulosic material was characterized by several physical and chemical techniques (IR, TGA, contact angle measurement, SEM, and back titration) to determine the extent of acylation and assess their morphological properties. The derivatized …

First Optimization Of Novel, Potent, Selective Pde11a4 Inhibitors For Age-Related Cognitive Decline, Shams Ul Mahmood, Mariana Lozano Gonzalez, Sreedhar Tummalapalli, Jeremy Eberhard, Judy Ly, Charles S. Hoffman, Michy P. Kelly, John Gordon, Dennis Colussi, Wayne Childers, David P. Rotella

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Phosphodiesterase 11A4 (PDE11A4) is a dual-acting cyclic nucleotide hydrolase expressed in neurons in the CA1, subiculum, amygdalostriatal transition area and amygdalohippocampal area of the extended hippocampal formation. PDE11A4 is the only PDE enzyme to emanate solely from hippocampal formation, a key brain region for the formation of long-term memory. PDE11A4 expression increases in the hippocampal formation of both humans and rodents as they age. Interestingly, PDE11A knockout mice do not show age-related deficits in associative memory and show no gross histopathology. This suggests that inhibition of PDE11A4 might serve as a therapeutic option for age-related cognitive decline. A novel, yeast-based …

Introductory Chemistry, Mona Muzammil

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

Introductory Chemistry, this edition is designed for a one-semester, introductory or preparatory chemistry course. Students taking this course need to develop problem-solving skills-but they also must see why these skills are important to them and to their world. Introductory Chemistry extends chemistry from the laboratory to the student's world. It motivates students to learn chemistry by demonstrating how it plays out in their daily lives.

This book draws students into the course through engagement and building their foundational knowledge – while introducing new content and resources to help students build critical thinking and problem-solving skills. allowing students flexibility and ensuring …

Pyrimidine Biosynthesis And Ribonucleoside Metabolism In Species Of Pseudomonas, Thomas P. West

Faculty Publications

Pyrimidine biosynthesis and ribonucleoside metabolism in species of Pseudomonas was the focus of this review, in relation to their current taxonomic assignments in different homology groups. It was of interest to learn whether pyrimidine biosynthesis in taxonomically related species of Pseudomonas was regulated in a similar fashion by pyrimidine base supplementation or by pyrimidine limitation of pyrimidine auxotrophic strains. It was concluded that the regulation of pyrimidine biosynthesis in Pseudomonas species could not be correlated with their taxonomic assignment into a specific homology group. Pyrimidine ribonucleoside metabolism in Pseudomonas species primarily involved the pyrimidine ribonucleoside salvage enzymes nucleoside hydrolase and …

Electrospun Nanofibers: Shaping The Future Of Controlled And Responsive Drug Delivery., Michael Joshua Wildy, Ping Lu

College of Science & Mathematics Departmental Research

Electrospun nanofibers for drug delivery systems (DDS) introduce a revolutionary means of administering pharmaceuticals, holding promise for both improved drug efficacy and reduced side effects. These biopolymer nanofiber membranes, distinguished by their high surface area-to-volume ratio, biocompatibility, and biodegradability, are ideally suited for pharmaceutical and biomedical applications. One of their standout attributes is the capability to offer the controlled release of the active pharmaceutical ingredient (API), allowing custom-tailored release profiles to address specific diseases and administration routes. Moreover, stimuli-responsive electrospun DDS can adapt to conditions at the drug target, enhancing the precision and selectivity of drug delivery. Such localized API …