Physical Sciences and Mathematics Commons^™

Sorbent Enrichment Performance Of Aromatic Compounds From Diluted Liquid Solution, Le Meng

USF Tampa Graduate Theses and Dissertations

Sorbent enrichment is treated as the extend sample preparing method from liquid extraction. The theories of liquid extraction also extend to sorbent enrichment, which is based on the distribution equilibrium. With the development of advanced materials, sorbents have been improved dramatically in the past twenty years. Nowadays, more and more enrichment performance cannot be explained from the angle of distribution model.

Herein, the sorption model is emphasized in this study. As the majority exist, aromatic compounds are the focused class of analytes. This study analyzed the sorption from two factors, the interaction between adsorbate and sorbent from their aromaticity, and …

Structure-Based Design, Synthesis And Applications Of A New Class Of Peptidomimetics: 'Y-Aa Peptides And Their Derivatives, Ma Su

USF Tampa Graduate Theses and Dissertations

Peptidomimetics can mimic hierarchical structures of peptides and proteins. Thus, they are extensively studied for therapeutic applications. To break the limitation of backbones and frameworks and expand the peptidomimetics family, a new class of peptidomimetics - “γ-AApeptides” was developed. Design of γ-AApeptides is based on the chiral peptide nucleic acids (PNAs) backbone.

The World Health Organization estimates that one -third of all deaths in the world are on account of infectious diseases. AMPs are important because of their high activity against broad spectrum microbes, less susceptible to grow resistance and selectivity in binding to bacterial cells over human cells. γ-AApeptides …

Analysis And New Applications Of Metal Organic Frameworks (Mof): Thermal Conductivity Of A Perovskite-Type Mof And Incorporation Of A Lewis Pair Into A Mof., Wilarachchige D C B Gunatilleke

USF Tampa Graduate Theses and Dissertations

Metal organic frameworks have gained much attention due to their tunable pore sizes and very high surface areas. With the discovery many of these type materials the need has raised to look into new applications of theses porous frameworks. This thesis focuses on the synthesis of a new perovskite-type metal organic framework and measurement of its thermal conductivity in search of its applicability as a thermoelectric material. The second part of this work focuses on the synthesis of a metal organic framework incorporated with a Lewis pair for the first time. The optimum loading amount of the Lewis pair into …

Optimizing Peptide Fractionation To Maximize Content In Cancer Proteomics, Victoria Izumi

USF Tampa Graduate Theses and Dissertations

The purpose of the studies included in this thesis is to develop an effective an efficient method to study the proteome using separation and detection of peptides, when only a limited amount of sample, 10 micrograms of total protein or less, is available. The analysis will be applied to multiple myeloma cancer cells using ultra high-performance liquid chromatography-mass spectrometry for expression proteomics to illustrate utility. To detect low abundance peptides in a complex proteome, we use different strategies, including basic pH reversed-phase liquid chromatography (bRPLC), mass-to-charge fractionation in the mass spectrometer, and various liquid chromatography gradients to increase peptide separation …

Development Of Bioactive Peptidomimetics, Fengyu She

USF Tampa Graduate Theses and Dissertations

Peptidomimetics are synthetic foldamers that expected more resistant to proteolytic degradation and enormous chemodiversity when compared with peptides. To date, the functional peptidomimetics such as β-peptides, peptoids, oligoureas, etc have been developed in many science fields. In order to explore the unnatural foldameric architectures, it’s necessary to discover the novel frameworks and molecular scaffolds. γ-AApeptides were reported to be a new class of peptidomimetics that showed its potential applications in drug discovery and chemical biology. However, a wide function and property of γ-AApeptides need to be further explored. To expand the potential application of γ-AApeptides in biochemistry, I have been …

Germania-Based Sol-Gel Coatings And Core-Shell Particles In Chromatographic Separations, Chengliang Jiang

USF Tampa Graduate Theses and Dissertations

Chapter one reviewed the development of sol-gel stationary phase for gas chromatograph (GC). Inorganic sol-gel precursor creates the substrate support for stationary phase bind to silica surface through the condensation of silanol groups, the rough surface with enhanced surface area enlarger the capacity of the sol-gel stationary phase, the porosity of sol-gel structure decreases the mass transferring coefficient, the term C in Van Deemter equation, which makes sol-gel stationary phase thicker coating up to 1 um but keeps the high resolution for gas chromatography. Chemical bound stationary phase significantly improve GC column with better thermal stability and solvent stability. Partial …

Interrogation Of Protein Function With Peptidomimetics, Olapeju Bolarinwa

USF Tampa Graduate Theses and Dissertations

Proteins can be described as the “machineries” responsible for almost all tasks in the levels of organizational complexity in multi-cellular organisms namely: the cells, tissues, organs and systems. Any disorder in the function of a protein at any of these levels could result in disease, and a study of protein function is critical to understanding the pathological features of the disease at the molecular level. A quick glance at these abundantly present proteins reveals two striking features: large diversity of biological function, and the variations in structural complexity, which varies from simple random coils, to turns and helices, and on …

Chemical Investigation Of Bioactive Marine Extracts, Selam Hagos

USF Tampa Graduate Theses and Dissertations

Natural products have been a fundamental source of medicinal scaffolds for decades; with sixty percent of marketed drugs. Many synthetic chemists are focused on synthesizing potent and nontoxic compounds for pharmaceutical targets, however, nature is still proving to be a source of new bioactive compounds. Produced by the host organism for defense, reproduction and communication, secondary metabolites also demonstrate promising bioactivity against human pathogens. Hence, natural product chemists continue their quest for new leads.

As a continuation of these efforts, this thesis attempts to explore fungi and sponges for new chemistry, and ultimately, new drug candidates. Antarctica is largely untapped; …

Quantitative Proteomics To Support Translational Cancer Research, Melissa Hoffman

USF Tampa Graduate Theses and Dissertations

Altered signaling pathways, which are mediated by post-translational modifications and changes in protein expression levels, are key regulators of cancer initiation, progression, and therapeutic escape. Many aspects of cancer progression, including early carcinogenesis and immediate response to drug treatment, are beyond the scope of genetic profiling and non-invasive monitoring techniques. Global protein profiling of cancer cell line models, tumor tissues, and biofluids (e.g. serum or urine) using mass spectrometry-based proteomics produces novel biological insights, which support improved patient outcomes. Recent technological advances resulting in next-generation mass spectrometry instrumentation and improved bioinformatics workflows have led to unprecedented measurement reproducibility as well …

Survey Research In Postsecondary Chemistry Education: Measurements Of Faculty Members’ Instructional Practice And Students’ Affect, Rebecca E. Gibbons

USF Tampa Graduate Theses and Dissertations

Collection of data through survey-type measurements and analysis contributes rich, meaningful information to the chemical education research enterprise. This dissertation reports two strands of research that each contribute a “snapshot” of the state of chemical education on two different levels. The first uses survey research methods, collecting data from faculty members to learn about postsecondary chemistry education across the United States. The second uses survey instruments of student achievement emotions within the organic chemistry classroom, collecting longitudinal data to learn about the relationships of emotions with achievement over time. Both areas are of interest because chemical education research produces evidence-based …

Studies Aimed At The Synthesis Of Anti-Infective Agents, Ankush Kanwar

USF Tampa Graduate Theses and Dissertations

Infectious diseases continue to be a major concern worldwide. They are the second leading cause of death after heart disease. Factors such as an increasing global population, travel, urbanization, global climate change and evolution of pathogens have made infectious diseases more common. Infectious diseases, particularly neglected tropical diseases (NTDs) result in many deaths worldwide. Malaria and leishmaniasis are two common (NTDs) which affect low income countries around the globe. Low cost drugs with novel mechanism of action are required to tackle the growing resistances of parasites against current drugs used in the developing world, where most of the cases occur. …

From Florida To Antarctica: Dereplication Strategies And Chemical Investigations Of Marine Organisms, Matthew A. Knestrick

USF Tampa Graduate Theses and Dissertations

In the fight against disease and illness, nature has provided mankind some of our best therapeutics in the form of secondary metabolites. The plant, fungi and animal phyla inhabiting the Earth produce diverse and unique chemistry that can be used in our fight against disease. In the growing threat of drug resistance and pathogen evolution, the field of natural products chemistry strives to explore new biological and chemical diversity sources, and develop innovative methodology to identify and isolate new chemistry faster than ever.

The dissertation herein presented is one such effort to find new, bioactive chemistry from the marine environments. …

Azamacrocyclic-Based Frameworks: Syntheses And Characterizations, Chavis Andrew Stackhouse

USF Tampa Graduate Theses and Dissertations

Research in metal-organic frameworks (MOFs) has risen greatly in recent decades Owing to their unequaled potential tunability and structural diversity. MOFs may be described as crystalline structures composed of metal cations or clusters of cations, commonly referred to as secondary building units (SBUs), and custom-designed organic ligands. The variety of structural motifs, ligands, and SBUs that may be incorporated promote the attainment of essentially countless potential MOFs and application in numerous areas of interest, such as gas adsorption, catalysis, gas separation, and sensing. Further functionalization of MOF materials by means of post-synthetic modification(PSM)33–37 of metal clusters or organic ligands, constructing …

Characterization Of Nylon-12 In A Novel Additive Manufacturing Technology, And The Rheological And Spectroscopic Analysis Of Peg-Starch Matrix Interactions, Garrett Michael Craft

USF Tampa Graduate Theses and Dissertations

In this work differential scanning calorimetry, dynamic mechanical analysis, Fourier-Transformed Infrared Spectroscopy [FT-IR] and polarized light microscopy will be employed to characterize polymeric systems. The first chapter broadly covers polymer synthesis and important characterization methods.

In the second chapter, a polyamide (PA12) will be sintered via a novel additive manufacturing (AM) technology developed here at USF termed LAPS (Large Area Projection Sintering). LAPS uses extended sintering timespans to ensure complete melting and densification of the polymer powder over the entire two-dimensional area of the part’s footprint. Further, it allows for the printed layer to crystallize and shrink in its entirety …

Elastin-Like Polypeptide Fusion Tag As A Protein-Dependent Solubility Enhancer Of Cysteine-Knot Growth Factors, Tamina L. Johnson

USF Tampa Graduate Theses and Dissertations

Elastin-like peptide (ELP) fusions promote therapeutic delivery and efficacy. Recombinant proteins, like neurotrophins, lack bioavailability, have short in vivo half-lives, and require high manufacturing costs. Fusing recombinant proteins with genetically encodable ELPs will increase bioavailability, enhance in vivo solubilization, as well as provide a cost-effective method for purification without the need for chromatography. During expression of neurotrophin-ELP (N-ELP) fusions, dense water-insoluble aggregates known as inclusion bodies (IBs) are formed. Inclusion bodies are partially and misfolded proteins that usually require denaturants like Urea for solubilization. Strong denaturants arrest ELPs stimuli-responsive property and increase unwanted aggregation, making purification difficult, yet possible. The …

Synthesis Of Novel Agents For The Treatment Of Infectious And Neurodegenerative Diseases, Benjamin Joe Eduful

USF Tampa Graduate Theses and Dissertations

Infectious and neurodegenerative diseases continue to be a major concern worldwide. In spite of the great advances in drug therapy for treating various infectious and neurodegenerative diseases, there is still an urgent need for new and improved drugs due to increasing drug resistance among pathogens, emergence of new pathogens, ease of transmission of infections, ineffective available treatments, toxicity associated with current standard of care, aging populations and the lack of better alternative treatment options.

The first part of this manuscript (chapters 1 - 5) describes the synthesis of novel agents active against Leishmania donovani. According to the World Health Organization …

Synthesis, Modification, Characterization And Processing Of Molded And Electrospun Thermoplastic Polymer Composites And Nanocomposites, Tamalia Julien

USF Tampa Graduate Theses and Dissertations

This dissertation focuses on the versatility and integrity of a novel, ultrasoft polycarbonate polyurethane (PCPU) by the introduction of nanoparticles and lithium salts. Additionally, the research takes into account the use of electrospinning as a technique to create PCPU and polyimide (PI) fibers. These polymers are of interest as they offer a wide range of properties and uses within the medical and industrial fields.

An industrial batch of an ultrasoft thermoplastic polyurethane (TPU) was synthesized using a two-step process. The first was to create an end capped pre-polymer from methylene bis (4-cyclohexylisocyanate), and a polycarbonate polyol made up of 1,6- …

Design, Synthesis, Application Of Biodegradable Polymers, Mussie Gide

USF Tampa Graduate Theses and Dissertations

Bacterial infections have posed a serious threat to the public health due to the significant rise of the infections caused by antibiotic-resistant bacteria. There has been considerable interest in the development of antimicrobial agents which mimic the natural HDPs, and among them biodegradable polymers are newly discovered drug candidates with ease of synthesis and low manufacture cost compared to synthetic host defense peptides. Herein, we present the synthesis of biocompatible and biodegradable polymers including polycarbonate polymers, unimolecular micelle hyperbranched polymers and dendrimers that mimic the antibacterial mechanism of HDPs by compromising bacterial cell membranes. The developed amphiphilic polycarbonates are highly …

Supported Perovskite-Type Oxides: Establishing A Foundation For Co2 Conversion Through Reverse Water-Gas Shift Chemical Looping, Bryan J. Hare

USF Tampa Graduate Theses and Dissertations

Perovskite-type oxides show irrefutable potential for feasible thermochemical solar-driven CO₂ conversion. These materials exhibit the exact characteristics required by the low temperature reverse water-gas shift chemical looping process. These properties include structural endurance and high oxygen redox capacity, which results in the formation of numerous oxygen vacancies, or active sites for CO₂ conversion. A major drawback is the decrease in oxygen self-diffusion with increasing perovskite particle size. In this study, the La_0.75Sr_0.25FeO₃ (LSF) perovskite oxide was combined with various supports including popular redox materials CeO₂ and ZrO₂ along with more abundant …