Digital Commons Network^™

Recent Advances In The Synthesis And Application Of Sf5-Containing Organic Compounds, Andrej V. Matsnev, Steven P. Belina, Si-Yan Qing, Kyle A. Berger, Anthony R. Scavuzzo, Piotr Dudzinski, Anna-Lena Dreier, Günter Haufe, Joseph S. Thrasher

Chemistry Annual Research Symposium

It is well known that fluorinated molecules play an important role in daily life. For example, organic molecules bearing either a fluorine atom itself or a short polyfluorinated substituent such as mono-, difluoro-, and trifluoromethyl groups, or pentafluoroethyl and perfluoropropyl groups are already widely used in medicinal and agricultural chemistry. In contrast, molecules with long perfluorinated chains have found vast application in materials science. Among the fluorine-containing moieties, the pentafluorosulfanyl (SF5) substituent occupies a special place.1 The pentafluorosulfanyl group brings unique properties to organic compounds and often improves their biological activities due to the group’s high chemical and metabolic stability, …

Liquid Sampling-Atmospheric Pressure Glow Discharge Ion Source For Nonproliferation Of Nuclear Material, Edward Hoegg, R. Kenneth Marcus, Charles Barinaga, George Hager, David Koppenaal, Garret Hart

Chemistry Annual Research Symposium

An area of continuing intense interest has been the development of portable or fieldable (man-portable, luggable, or transportable) analytical instrumentation. One specific driver for portable or fieldable analytical instrumentation are the needs of the nuclear safeguards community for versatile, easy-to-use, in-field mass spectrometer systems for determining the 235U/238U isotope ratios in UF6 at enrichment facilities. In order to meet this demand the authors propose using a liquid sampling-atmospheric pressure glow discharge (LS-APGD) ion source, Fig 1.1-3 The LS-APGD was optimized for isotope ratio analysis to have a liquid flow rate of 30 uL min-1 a gas flow rate of 0.5 …

Ua66 Ogden College Of Science & Engineering Newsletter, Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.

Uplc–Qtof–Ms And Nmr Analyses Of Graviola (Annona Muricata) Leaves, Ingrid De Moraes, Paulo Ribeiro, Flávio Schmidt, Kirley Canuto, Guilherme Zocolo, Edy De Brito, Rensheng Luo, Kristy Richards, Kevin Tran, Robert Smith

Chemistry & Biochemistry Faculty Works

No abstract provided.

Creation Of A New Type Of Ion Exchange Material For Rapid, High-Capacity, Reversible And Selective Ion Exchange Without Swelling And Entrainment, Baiyan Li, Yiming Zhang, Dingxuan Ma, Zhenyu Xing, Tianliang Ma, Zhan Shi, Xiulei Ji, Shengqian Ma

Chemistry Faculty Publications

Ion-exchange materials, currently dominated by resins, are widely used in a plethora of areas. However, the drawbacks of conventional resins necessitate the creation of a new model of ion exchange materials that feature controllable swelling, easily accessible ion exchange sites, high ion exchange capacity, fast ion exchange kinetics, and high chemical stability as illustrated herein in the context of functionalizing a porous organic polymer (POP) with ion exchange groups. The advantages of POP-based ion exchange materials in comparison with conventional resins and other types of ion exchange materials have been highlighted through an evaluation of their performances in scavenging precious …

Development And Application Of New Solid-State Models For Low-Energy Vibrations, Lattice Defects, Entropies Of Mixing, And Magnetic Properties, Jacob M. Schliesser

Theses and Dissertations

Low-temperature heat capacity data contain information on the physical properties of materials, and new models continue to be developed to aid in the analysis and interpretation of heat capacity data into physically meaningful properties. This work presents the development of two such models and their application to real material systems. Equations describing low-energy vibrational modes with a gap in the density of states (DOS) have been derived and tested on several material systems with known gaps in the DOS, and the origins of such gaps in the DOS are presented. Lattice vacancies have been shown to produce a two-level system …

Development Of A Direct Activity Probe For Rho-Associated Protein Kinase, Maia Kelly

Department of Chemistry: Dissertations, Theses, and Student Research

Hepatocellular carcinoma (HCC) is an extremely aggressive form of liver cancer with a low survival rate due to high recurrence. Increases in Rho-associated Protein Kinase (ROCK) activity are correlated with a more aggressive, metastatic phenotype associated with advanced HCC. Inhibitors for ROCK have shown potential for the reduction of this metastatic phenotype of HCC. We outline the design and optimization of a direct activity sensor for ROCK that utilizes a phosphorylation-sensitive sulfonamido-oxine fluorophore, termed Sox, and is capable of reporting on the inhibition of ROCK. This CSox-based activity probe utilizes chelation-enhanced fluorescence (ex. = 360 nm and em. = 485 …

Discovery Of Low-Molecular Weight Novel Serum Biomarkers For Diagnosing Preeclampsia And Alzheimer's Disease, Swati Anand

Theses and Dissertations

Preeclampsia (PE), a life threatening pregnancy-related disorder, is characterized mainly by new onset of hypertension and proteinuria after 20 weeks of gestation. Currently, PE cannot be predicted prior to onset of symptoms and there is no cure for the disease. There is a clear value in having biomarkers able, early in a pregnancy, to identify women at risk for PE so that proper treatment therapies could be developed. Although a number of serum candidate markers have been proposed to be altered in PE patients, their use is limited due to poor sensitivity and specificity. Therefore, there is ongoing need for …

14-3-3Ζ Regulation Of Metastasis Through Mediation Of Liprin-Α And Liprin-Β, Rachel Hynes

Theses and Dissertations

Cancer is a set of varied and diverse diseases that share common characteristics, such as active proliferation, increased replicative potential, and tissue invasion or metastasis. One protein, 14-3-3ζ, is shown to be upregulated in a number of different cancers and also correlates with poor patient prognosis, recurrence, and mortality. This protein comes from a family of adapter proteins known for their scaffolding ability, pro- and anti-oncogenic capabilities, and affinity for phosphorylated substrates. It has been shown previously to participate in cancer progression, subversion of apoptosis, and to increase chemoresistance. Herein we will discuss the ability of 14-3-3ζ to promote distant-site …

1h, 13c And 15n Resonance Assignments And Secondary Structure Analysis Of Translation Initiation Factor 1 From Pseudomonas Aeruginosa, Alejandra Bernal, Yanmei Hu, Stephanie O. Palmer, Aaron Silva, James M. Bullard, Yonghong Zhang

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

Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen and a primary cause of infection in humans. P. aeruginosa can acquire resistance against multiple groups of antimicrobial agents, including β-lactams, aminoglycosides and fluoroquinolones, and multidrug resistance is increasing in this organism which makes treatment of the infections difficult and expensive. This has led to the unmet need for discovery of new compounds distinctly different from present antimicrobials. Protein synthesis is an essential metabolic process and a validated target for the development of new antibiotics. Translation initiation factor 1 from P. aeruginosa (Pa-IF1) is the smallest of the three initiation factors that acts …

Forcespinning: A New Method For The Mass Production Of Sn/C Composite Nanofiber Anodes For Lithium Ion Batteries, Victor Agubra, Luis Zuniga, David De La Garza, Luis Gallegos, Madhab Pokhrel, Mataz Alcoutlabi

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

The development of nanostructured anode materials for rechargeable Lithium-ion Batteries has seen a growing interest. We herein report the use of a new scalable technique, Forcespinning (FS) to produce binder-free porous Sn/C composite nanofibers with different Sn particle size loading. The preparation process involves the FS of Sn/PAN precursor nanofibers and subsequently stabilizing in air at 280 °C followed by carbonization at 800 °C under an inert atmosphere. The Sn/C composite nanofibers are highly flexible and were directly used as binder-free anodes for lithium-ion batteries. The produced Sn/C composite nanofibers showed an improved discharge capacity of about 724 mA …

Fluorescence Of Supported Phospholipid Bilayers Recorded In A Conventional Horizontal-Beam Spectrofluorometer, Elizaveta A. Kovrigina, Evgeni L. Kovrigin

Chemistry Faculty Research and Publications

Supported phospholipid bilayers are a convenient model of cellular membranes in studies of membrane biophysics and protein-lipid interactions. Traditionally, supported lipid bilayers are formed on a flat surface of a glass slide to be observed through fluorescence microscopes. This paper describes a method to enable fluorescence detection from the supported lipid bilayers using standard horizontal-beam spectrofluorometers instead of the microscopes. In the proposed approach, the supported lipid bilayers are formed on the inner optical surfaces of the standard fluorescence microcell. To enable observation of the bilayer absorbed on the cell wall, the microcell is placed in a standard fluorometer cell …

Fabrication Of Riboflavin Electrochemical Sensor Based On Au Nanoparticles/Polydopamine/Carbon Nanotubes Modified Glassy Carbon Electrode, Hua-Ping Peng, Mei-Ling Yu, Xin Liu, Pan Liu, Wei Chen, Ai-Lin Liu, Xin-Hua Lin

Journal of Electrochemistry

A novel electrochemical platform for the high sensitivity detection of riboflavin was constructed by Au nanoparticles/polydopamine/carbon nanotubes (Au-PDA-MWCNTs) nanocomposite modified glassy carbon electrode. The Au-PDA-MWCNTs nanocomposite was synthesized by in situ reduction method. The characteristics of the as-prepared Au-PDA-MWCNTs nanocomposite modified electrodes were investigated by using UV-Vis spectroscopy, scanning electron microscopy (SEM) and electrochemical methods. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to study the electrochemical behavior of riboflavin (RF) at Au-PDA-MWCNTs nanocomposite modified electrodes. The results demonstrated that the present electrochemical sensor exhibited a wide linear range from 5×10^-9 mol•L^-1to 1×10^-5 mol•L …

An Electrochemical Investigation Of P-Sulfophenylazo Calix[4]Arene In A Buffer Solution, Xing Yang, Ping Chen

Journal of Electrochemistry

The p-sulfophenylazo calix[4]arene was synthesized through the diazotization-coupling reaction between calix[4]arene and p-aminobenzene sulfonic acid. The UV-Vis spectroscopy, Infrared spectroscopy, and nuclear magnetic resonance (NMR) were used to characterize the as-prepared p-sulfophenylazo calix[4]arene. The electrochemical behaviors of p-sulfophenylazo calix[4]arene were investigated by cyclic voltammetry and chronoamperometry using CH₃COOH-CH₃COONa as a buffer solution. The result shows that the p-sulfophenylazo calix[4]arene exhibited a pair of redox peaks in a scan potential region of -0.5 ~ 1 V. The oxidation and reduction peak potentials were 0.302 V and -0.003 V, respectively, and changed with the scanning rates. In addition, …

Chemical Investigation Of Antarctic Marine Organisms & Their Role In Modern Drug Discovery, Jacqueline Lee Fries

USF Tampa Graduate Theses and Dissertations

The chemicals produced by biological systems, whether proteins, peptides, or terpenes, will always provide an intriguing topic for researchers. Invisibly controlling every aspect of nature, these molecules are responsible for life, evolution, and death. Specifically, here is described the secondary metabolites produced by Antarctic marine organisms as well as others, and how they are used to defend or attract other animals while potentially providing health benefits to mankind. This is done through collection, extraction, and separation of individual specimens. The respective mixtures of compounds after isolation are then analyzed via spectroscopic methods such as nuclear magnetic resonance spectroscopy, mass spectrometry, …

Development And Validation Of A Sensitive Uplc-Ms/Ms Method For The Quantitation Of [13c]Sucrose In Rat Plasma, Blood, And Brain: Its Application To The Measurement Of Blood-Brain Barrier Permeability, Mohammad K. Miah, Ulrich Bickel, Reza Mehvar

Pharmacy Faculty Articles and Research

Accurate and reproducible measurement of blood-brain barrier (BBB) integrity is critical in the assessment of the pathophysiology of the central nervous system disorders and in monitoring therapeutic effects. The widely-used low molecular weight marker [14C]sucrose is non-specific in the absence of chromatographic separation. The purpose of this study was to develop and validate a sensitive and reproducible LC-MS/MS method for the analysis of stable isotopemodified [13C12]sucrose in brain, plasma, and blood to determine BBB permeability to sucrose. After addition of internal standard (IS, [13C6]sucrose), the marker and IS were recovered from diluted rat blood, plasma, and brain homogenate by protein …

In Crystallo Capture Of A Covalent Intermediate In The Udp-Galactopyranose Mutase Reaction, Ritcha Mehra-Chaudhary, Yumin Dai, Pablo Sobrado, John J. Tanner

Chemistry Faculty Research & Creative Works

UDP-galactopyranose mutase (UGM) plays an essential role in galactofuranose biosynthesis in pathogens by catalyzing the conversion of UDP-galactopyranose to UDP-galactofuranose. Here we report the first crystal structure of a covalent intermediate in the UGM reaction. The 2.3 Å resolution structure reveals UDP bound in the active site and galactopyranose linked to the FAD through a covalent bond between the anomeric C of galactopyranose and N5 of the FAD. The structure confirms the role of the flavin as nucleophile and supports the hypothesis that the proton destined for O5 of galactofuranose is shuttled from N5 of the FAD via O4 of …

One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran

Dissertations and Theses

The key challenge for a nanomaterial based sensor is how to synthesize in bulk quantity and fabricate an actual device with insightful understanding of operational mechanisms during performance. I report here effective, controllable methods that exploit the concepts of the "green approach" to synthesize two different one-dimensional nanostructures, including tin oxide nanowires and carbon nanotubes. The syntheses are followed by product characterization and sensing device fabrications as well as sensor performance understanding at the molecular level. Sensor-analyte response and recovery kinetics are also presented.

The first part of the thesis describes bulk-scale synthesis and characterization of tin oxide nanowires by …

I Want To Be The Inquiry Guy! How Research Experiences For Teachers Change Beliefs, Attitudes, And Values About Teaching Science As Inquiry, Deborah Herrington, Senetta F. Bancroft, Molly M. Edwards, Caroline J. Schairer

Peer Reviewed Articles

This qualitative study examined how and why research experiences for teachers (RETs) influenced middle and high school science teachers’ beliefs, attitudes, and values about teaching science as inquiry. Changes teachers reported after participating in the RET ranged from modifying a few lessons (belief change) to a comprehensive revision of what and how they taught to better reflect inquiry (attitude change). Some teachers who described comprehensively changing their instruction also described implementing actions meant to change science education within their respective schools, not just their own classrooms (value change). We present how and why teachers went about changes in their practices …

Dissolved Organic Carbon From The Upper Rio Negro Protects Zebrafish (Danio Rerio) Against Ionoregulatory Disturbances Caused By Low Ph Exposure, Rafael M. Duarte, D. Scott Smith, Adalberto L. Val, Chris M. Wood

Chemistry Faculty Publications

The so-called “blackwaters” of the Amazonian Rio Negro are rich in highly coloured dissolved organic carbon (DOC), but ion-poor and very acidic, conditions that would cause fatal ionoregulatory failure in most fish. However these blackwaters support 8% of the world’s ichthyofauna. We tested the hypothesis that native DOC provides protection against ionoregulatory dysfunction in this extreme environment. DOCs were isolated by reverse-osmosis from two Rio Negro sites. Physico-chemical characterization clearly indicated a terrigenous origin, with a high proportion of hydroxyl and phenolic sites, high chemical reactivity to protons, and unusual proteinaceous fluorescence. When tested using zebrafish (a model organism), Rio …

Design, Synthesis And Screening Of Peptidomimetics For Anticancer And Antiviral Drug Candidates, Yi Liang

USF Tampa Graduate Theses and Dissertations

The high demand of novel peptide and peptidomimetics based on the amount of genomic and proteomic data need be matched by synthesis and screening. The design and synthesis of peptide and peptidomimetics are so important because the peptide and protein-protein interaction play a key role in molecule recognition and signaling. The modified peptides have better stability and pharmacokinetic properties which may be guided by rational design and molecular modeling. Now many organic and medicinal chemists have chosen peptide and peptidomimetics as potential drug candidates for many targets.

In this dissertation, research efforts in design and synthesis of cyclic peptides with …

Structural Dependence Of The In Vitro Cytotoxicity, Oxidative Stress And Uptake Mechanisms Of Poly(Propylene Imine) Dendritic Nanoparticles, Humza Khalid, Sourav Prasanna Mukherjee, Luke O'Neill, Hugh Byrne

Articles

The in vitro cytotoxic and intracellular oxidative stress responses to exposure to poly (propylene imine) (PPI) dendritic nanoparticles of increasing generation (number of repeated branching cycles) (G0-G4) were assessed in an immortal non-cancerous human keratinocyte cell-line (HaCaT). Confocal fluorescence microscopy with organelle staining was used to explore the uptake and intracellular trafficking mechanisms. A generation and dose dependent cytotoxic response was observed, increasing according to generation and therefore number of surface amino groups. A comparison of the cytotoxic response of G4 PPI and the related G4 Poly (amido amine) dendrimer indicates that the PPI with the same number of surface …

Design Rules For The Nucleation, Growth, And Encapsulation Of Gold Nanoparticles With Applications To Cancer Imaging, Matthew A. Wall

Dissertations, Theses, and Capstone Projects

Surface-enhanced Raman scattering (SERS) nanoparticles are exciting candidates for high-precision cancer imaging due to their highly specific spectral signature (Raman “fingerprint”) and propensity for passive targeting of cancerous tissues. However, the signal intensity of currently available SERS nanoparticles is insufficient for cancer imaging via passive targeting in most solid tumors. The overarching aim of this body of work is to develop a new generation of SERS nanoparticles with sufficiently low limits of detection to enable robust detection of various solid tumors in vivo.

The complexity of SERS nanoparticles requires significant advances to the theoretical and experimental understanding of metal …

Ultrafast Spectroscopy And Energy Transfer In An Organic/Inorganic Composite Of Zinc Oxide And Graphite Oxide, Jeff A. Secor

Dissertations, Theses, and Capstone Projects

The energy transfers and nature of defect levels of an organic/inorganic composite of Zinc Oxide and Graphite are studied with multidimensional spectroscopy. The edge and surface states of each composite are uncovered using excitation emission experiments showing which defect states are mediating the energy transfer from the metal oxide to the graphite oxide. Multidimensional time resolved spectroscopy further describes the effect of the carbon phase on the energy transfer pathways in the material.

Synthesis Of Novel Aporphine-Inspired Neuroreceptor Ligands, Nirav R. Kapadia

Dissertations, Theses, and Capstone Projects

Aporphines are a group of tetracyclic alkaloids that belong to the ubiquitous tetrahydroisoquinoline family. The aporphine template is known to be associated with a range of biological activities. Aporphines have been explored as antioxidants, anti-tuberculosis, antimicrobial and anticancer agents. Within the Central Nervous Systems (CNS), aporphine alkaloids are known to possess high affinity for several clinically valuable targets including dopamine receptors (predominantly D₁ and D₂), serotonin receptors (5-HT_1A and 5-HT₇) and α adrenergic receptors. Aporphines are also inhibitors of the acetylcholinesterase enzyme – a clinical target for the treatment of Alzheimer’s disease. Considering the …

Study Of Infrared Emission Spectroscopy For The B 1Δg- A 1Πu And B ′1Σg +- A 1Πu Systems Of C2, Wang Chen, Kentarou Kawaguchi, Peter F. Bernath, Jian Tang

Chemistry & Biochemistry Faculty Publications

Thirteen bands for the B¹Δ_g-A¹Π_u system and eleven bands for the B′¹Σ_g ⁺-A¹Πu system of C₂ were identified in the Fourier transform infrared emission spectra of hydrocarbon discharges. The B′¹Σ_g ⁺ v = 4 and the B¹Δ_g v = 6, 7, and 8 vibrational levels involved in nine bands were studied for the first time. A direct global analysis with Dunham parameters was carried out satisfactorily for the B¹Δ_g-A¹Π_u system except for a …

Binding Of Transcription Factor Gabr To Dna Requires Recognition Of Dna Shape At A Location Distinct From Its Cognate Binding Site, Dali Liu, Walid A. Al-Zyoud, Robert Mg. Hynson, Lorraine A. Ganuelas, Adelle Cf. Coster, Anthony P. Duff, Matthew Ab. Baker, Alastair G. Stewart, Eleni Giannoulatou, Joshua Wk> Ho, Katharina Gaus, Lawrence K. Lee, Till Böcking

Chemistry: Faculty Publications and Other Works

Mechanisms for transcription factor recognition of specific DNA base sequences are well characterized and recent studies demonstrate that the shape of these cognate binding sites is also important. Here, we uncover a new mechanism where the transcription factor GabR simultaneously recognizes two cognate binding sites and the shape of a 29 bp DNA sequence that bridges these sites. Small-angle X-ray scattering and multi-angle laser light scattering are consistent with a model where the DNA undergoes a conformational change to bend around GabR during binding. In silico predictions suggest that the bridging DNA sequence is likely to be bendable in one …

Effects Of A Pyrrole-Based, Microtubule-Depolymerizing Compound On Raw 264.7 Macrophages, John A. Ciemnieckia, Clarke P. Lewis, John T. Gupton, Krista J. Stenger

Biology Faculty Publications

RAW 264.7 murine macrophages were exposed to the pyrrole-based compound 3,5-Dibromo-4-(3,4-dimethoxyphenyl)-1H-pyrrole-2-carboxylic acid ethyl ester (JG-03-14), which is a known microtubule depolymerizing agent with antitumor activity [1,2,3]. In this study exposure to JG-03-14 reduced the production of pro-inflammatory molecules by macrophages activated with lipopolysaccharide (LPS). Treatment with the pyrrole-based compound decreased the concentration of tumor necrosis factor-α (TNF-α) and nitric oxide (NO) released from the macrophages. Exposure to JG-03-14 also decreased TNF-α mRNA expression levels and the protein expression levels of inducible nitric oxide synthase (iNOS), the enzyme responsible for NO production in the activated macrophages. Furthermore, JG-03-14 treatment significantly changed …

The Elusive Quest For Rna Knots, Aaron S. Burton, Marco Di Stefano, Niles Lehman, Henri Orland, Cristian Micheletti

Chemistry Faculty Publications and Presentations

Physical entanglement, and particularly knots arise spontaneously in equilibrated polymers that are sufficiently long and densely packed. Biopolymers are no exceptions: knots have long been known to occur in proteins as well as in encapsidated viral DNA. The rapidly growing number of RNA structures has recently made it possible to investigate the incidence of physical knots in this type of biomolecule, too. Strikingly, no knots have been found to date in the known RNA structures. In this Point of View Article we discuss the absence of knots in currently available RNAs and consider the reasons why knots in RNA have …

Metabolic Disorders, Drug Development, Drug Design And Biomarkers, Gjumrakch Aliev, Ramon Cacabelos, V. Prakash Reddy

Chemistry Faculty Research & Creative Works

No abstract provided.