Chemistry Commons^™

Encapsulating Ibuprofen Using Beeswax Microspheres, Honghao Li, Kermin Martinez-Hernandez

Undergraduate External Publications

Beeswax is extremely versatile, often used in candles, lubricants. This compound is readily available and is not very expensive. We are interested in using beeswax as a biodegradable capsule to self-encapsulate drugs like ibuprofen.

Photocatalytic Properties Of G-C3n4–Tio2 Heterojunctions Under Uv And Visible Light Conditions, Rachel Fagan, Declan Mccormack, Steven J. Hinder, Suresh Pillai

Articles

Graphitic carbon nitride (g-C3N4) and titanium dioxide (TiO2) were chosen as a model system to investigate photocatalytic abilities of heterojunction system under UV and visible light conditions. The use of g-C3N4 has been shown to be effective in the reduction in recombination through the interaction between the two interfaces of TiO2 andg-C3N4. A simple method of preparing g-C3N4 through the pyrolysis of melamine was employed, which was then added to undoped TiO2 material to form the g-C3N4–TiO2 system. These materials were then fully characterized by X-ray diffraction (XRD), Brunauer Emmett Teller (BET), and various spectroscopic techniques including Raman, X-ray photoelectron …

Titanium-Oxides As A Stabilizing Agent For Environmentally Persistent Free Radicals (Epfrs), Josef Baylis

Scholarly and Creative Works Conference (2015 - 2021)

The mechanism of formation for surface bound radicals were studied using ab initio quantum methods. The shift in electron density from transition metal surfaces to surface bound radical groups was studied to learn the mechanism for the binding. Results indicate an oxidation-reduction based mechanism of formation.

Titanocene−Gold Complexes Containing N‑Heterocyclic Carbene Ligands Inhibit Growth Of Prostate, Renal, And Colon Cancers In Vitro, Yiu Fung Mui, Jacob FernáNdez-Gallardo, Benelita T. Elie, Ahmed Gubran, Irene Maluenda, Mercedes Sanau, Marıá Contel

Publications and Research

We report on the synthesis, characterization, and stability studies of new titanocene complexes containing a methyl group and a carboxylate ligand (mba = −OC(O)-p-C6H4-S−) bound to gold(I)−N-heterocyclic carbene fragments through the thiolate group: [(η5-C5H5)2TiMe(μ-mba)Au(NHC)]. The cytotoxicities of the heterometallic compounds along with those of novel monometallic gold−N-heterocyclic carbene precursors [(NHC)Au(mbaH)] have been evaluated against renal, prostate, colon, and breast cancer cell lines. The highest activity and selectivity and a synergistic effect of the resulting heterometallic species was found for the prostate and colon cancer cell lines. The colocalization of both titanium and gold metals (1:1 ratio) in PC3 prostate cancer …

Agonist-Mediated Activation Of Sting Induces Apoptosis In Malignant B Cells, Chih-Hang Anthony Tang, Joseph A. Zundell, Sujeewa Ranatunga, Cindy Lin, Yulia Nefedova, Juan R. Del Valle, Chih-Chi Andrew Hu

Chemistry Faculty Publications

Endoplasmic reticulum (ER) stress responses through the IRE-1/XBP-1 pathway are required for the function of STING (TMEM173), an ER-resident transmembrane protein critical for cytoplasmic DNA sensing, IFN production, and cancer control. Here we show that the IRE-1/XBP-1 pathway functions downstream of STING and that STING agonists selectively trigger mitochondria-mediated apoptosis in normal and malignant B cells. Upon stimulation, STING was degraded less efficiently in B cells, implying that prolonged activation of STING can lead to apoptosis. Transient activation of the IRE-1/XBP-1 pathway partially protected agonist-stimulated malignant B cells from undergoing apoptosis. In Eμ-TCL1 mice with chronic lymphocytic leukemia, injection of …

Removal Of Arsenic From Water Using Synthetic Fe7s8 Nanoparticles, Jesus Cantu, Louis E. Gonzalez, Jacqueline Goodship, Monica Contreras, Meera Joseph, Cameron Garza, Thomas Eubanks, Jason Parsons

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

In the present study, pyrrhotite was used to remove arsenite and arsenate from aqueous solutions. The Fe7S8 was synthesized using a solvothermal synthetic method and it was characterized using XRD and SEM micrographs. Furthermore, the particle size for the nanomaterial Fe7S8 was determined to be 29.86 ± 0.87 nm using Scherer’s equation. During the pH profile studies, the optimum pH for the binding of As (III) and As (V) was determined to be pH 4. Batch isotherm studies were performed to determine the binding capacity of As(III) and As(V), which was determined to be 14.3 mg/g and 31.3 mg/g respectively …

The Level Of Polyaromatic Hydrocarbon Contamination On The Kalamazoo River Shoreline Remains High Following The 2010 Enbridge Oil Spill, Wisam Abdulabbas Flayyih Al Isawi

Research and Creative Activities Poster Day

• One of the nation’s worst inland oil spills occurred near Marshall in Michigan in 2010.
• The recent Enbridge Line 6B rupture released over three million liters of diluted bitumen crude oil into the environment.
• The spilled oil entered the Talmadge Creek and flowed into the Kalamazoo River, a Lake Michigan tributary.
• Polycyclic Aromatic Hydrocarbons (PAHs) together with other pollutants were released into the environment.
• PAHs represents significant threats to aquatic organisms due to their carcinogenic and mutagenic properties and their persistence in the environment.
• Five years following the oil spill accident, the levels and identities of PAHs were investigated in …

Selective Incarceration And Extraction Of Oxoanion Contaminants From Aqueous Media By Self-Assembled Nanojars, Basil Ahmed

Research and Creative Activities Poster Day

Selective binding and extraction of anions by artificial receptors is one of the most far‐reaching areas of supramolecular chemistry, with implications in chemical, biological and environmental sciences. The extraction of kosmotropic anions from aqueous media is challenging, due to their large hydration energies (affinity for water). We have recently shown that a class of toroidal copper(II)‐hydroxide/pyrazolate complexes (nanojars), with the formula [Cu(OH)(pz)]_n (n = 27−36), totally incarcerate kosmotropic anions with an unprecedented strength. Lined by H‐bond donors on the inside and hydrophobic on the outside, these ~2 nm sized assemblies selectively extract kosmotropic anions from mixtures with chaotropic anions …

Ion Transfer Stripping Voltammetry Method Using Conductive Polymer To Low Concentration Detection Of Environmental Contaminants, Dinusha Udari Ranawaka Arachchige

Student Theses and Dissertations

Detecting environmental contaminants such as Selective serotonin reuptake inhibitors (SSRIs) and Cr (VI) compounds is essential since they are highly toxic contaminants of many drinking water supplies leading to adverse health effects. Selective serotonin reuptake inhibitors are common antidepressants therapeutics and fluoxetine; Prozac®, citalopram; Celexa® and sertraline; Zoloft® were successfully detected in this study. Ion transfer stripping voltammetry (ITSV) was applied to detect those as cations at nanomolar concentrations using an inexpensive and disposable pencil lead electrode, with a lower detection limit of 30 nM. The pencil lead electrode was modified using the conducting polymer Poly (3, 4-ethylenedioxythiophene) (PEDOT-C14) and …

Optimizing Chemical & Rheological Properties Of Rejuvenated Bitumen, Dominic Nguyen, Hamzeh Haghshenas Fatmehsari, Santosh Kommidi, Yong-Rak Kim

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Bitumen has long been a material used in the construction of roadways, yet new pavement only consists of low fractions of recycled materials due to poor compatibility of aged bitumen and new materials. Thus, rejuvenators, chemical additives, have been used in an attempt to re-balance the chemical composition and restore the physical properties of aged bitumen back to its virgin state. A fundamental understanding of how one particular rejuvenator, soybean oil, revitalizes bitumen was investigated using a multi-scale approach.

Fourier-transform infrared spectroscopy (FTIR) was used to determine the changes in chemical properties of pure and rejuvenated virgin and aged samples. …

Characterization Of Putative Peptidyl-Trna Hydrolase Ptrhd1, Geordan Burks

Research Horizons Day Posters

No abstract provided.

Big Changes For Small Noncovalent Dimers: Revisiting The Potential Energy Surfaces Of (P2)2 And (Pccp)2 With Ccsd(T) Optimizations And Vibrational Frequencies, Eric Van Dornshuld, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

This article details the re-examination of low-lying stationary points on the potential energy surfaces (PESs) of two challenging noncovalent homogeneous dimers, (P₂)₂ and (PCCP)₂. The work was motivated by the rather large differences between MP2 and CCSD(T) energetics that were recently reported for these systems (J. Comput. Chem. 2014, 35, 479-487). The current investigation reveals significant qualitative and quantitative changes when the CCSD(T) method is used to characterize the stationary points instead of MP2. For example, CCSD(T) optimizations and harmonic vibrational frequency computations with the aug-cc-pVTZ basis set indicate that the parallel-slipped (PS) structure is …

Optical Interfference I, Ronald Lovett

Topics in Quantum Mechanics

Using Huygens' Principle to Predict Optical Interference

Optical Interfference Ii, Ronald Lovett

Topics in Quantum Mechanics

Two Astronomical Observations Based on Interference

Chiral Boro-Phosphates In Asymmetric Catalysis: 1,4-Reduction Of Enones And Reductive Aldol, Susana Sorina Lopez

USF Tampa Graduate Theses and Dissertations

The biological activity of the pharmaceutical drugs often depends on how it fits with a receptor making stereochemistry a key component. Selective reactions can limit or avoid the mixture of enantiomers obtained. One such reaction is the selective reduction of a carbon-carbon double bond in the presence of a carbonyl. Although efficient, current asymmetric synthesis methods have limitations such as harsh reaction conditions, the high costs of chiral catalysts and the toxicity of the metal-based catalysts. Catalysts derived from small organic molecules have become an attractive alternative which have been explored more rigorously in recent years. Using a BINOL-derived boro-phosphate …

Photocatalytic Reduction Of Fumarate To Succinate On Zns Mineral Surfaces, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

The reductive tricarboxylic acid (rTCA) cycle is an important central biosynthetic pathway that fixes CO₂ into carboxylic acids. Among the five reductive steps in the rTCA cycle, the two-electron reduction of fumarate to succinate proceeds nonenzymatically on the surface of photoexcited sphalerite (ZnS) colloids suspended in water. This model reaction is chosen to systematically study the surface photoprocess occurring on ZnS in the presence of [Na₂S] (1–10 mM) hole scavenger at 15 °C. Experiments at variable pH (5–10) indicate that monodissociated fumaric acid is the primary electron acceptor forming the monoprotic form of succinic acid. The following …

Non-Traditional Hydrogen Bond Explanation Of Asymmetric Catalysis Of Mukaiyama Aldol Reactions By Dinuclear Zinc Semi-Crown Ligands, Ayan N. Ahmed, Brandon Vernier, Jeffrey Rohde, Jeffrey D. Evanseck

Undergraduate Research and Scholarship Symposium

Semi-crown ligands have been utilized in the asymmetric Mukaiyama aldol reactions involving enol silyl ethers; however, the factors that influence the stereoselectivity are not understood. Our previous work suggests that competition between the formyl and alpha hydrogen bonds between a chiral catalyst and the formyl or alpha hydrogen of the aldehyde play a critical role in the overall stereoselectivity. To understand the Mukaiyama aldol reaction, we investigate the Trost dinuclear zinc-based semi-crown ligand and its role in the reaction using the M06-2X functional paired with Dunning basis sets. Our discussion centers upon our energetic findings and consequences of the alpha …

Effects Of Macromolecular Crowding On Ferredoxin And Ferredoxin-Nadp+ Reductase Kinetics, Danielle Bautista, David W. Seybert Ph.D.

Undergraduate Research and Scholarship Symposium

Macromolecular crowding refers to the intrinsic occurrence of high concentrations of macromolecules found within cells, which may alter biomolecular properties of other macromolecules. Simulating these environments in vitro should enable a more accurate understanding of these modifications. We have employed in vitro studies to specifically examine the effects of macromolecular crowding on biological redox reactions. The iron-sulfur protein ferredoxin (Fdx) and the FAD-containing flavoprotein ferredoxin-NADP+ reductase (FNR), from Spinacea oleracea, were utilized as a model electron transfer system. Utilizing NADPH as a reductant, the Fdx-FNR complex reduces mammalian cytochrome c as a surrogate electron acceptor. Reduction of the heme moiety …

Macromolecular Crowding Effects Of Ldh, Sadiq Ali Shaik

Undergraduate Research and Scholarship Symposium

No abstract provided.

The Use Of Synthetic Mixture Based Libraries To Identify Hit Compounds For Eskape Pathogens, Leishmaniasis, And Inhibitors Of Palmitoylation, Marcello Giulianotti

USF Tampa Graduate Theses and Dissertations

The goal of this work is to demonstrate the utility of using systematically formatted mixture based libraries as part of the drug discovery processes. While there are a number of different valid approaches for identifying hit and tool compounds, systematically formatted mixture based libraries, such as those described in this study, offer the ability to develop a significant amount of structure activity relationship data from the testing of very few samples. In support of this claim a review of recent developments in the area of systematically formatted mixture based libraries as well as three case studies are presented. The three …

Co(Ii)-Based Metalloradical Catalysis For Asymmetric Radical Cyclopropanation, Qigan Cheng

USF Tampa Graduate Theses and Dissertations

Metal-catalyzed cyclopropanation of olefins with diazo reagents is one of the most general and efficient method to prepare cyclopropanes. The resulting cyclopropyl units are found as a basic structural element in a wide range of naturally occurring compounds and biologically active compounds, and can serve as versatile synthetic intermediates in the synthesis of multifunctionalized cycloalkanes and acyclic compounds. Since Co(II) complexes of D₂-symmetric chiral amidoporphyrins [Co(D₂-Por*)] were first introduced in 2004, Co(II)-metalloradical catalysis (MRC) have emerged as a new platform for asymmetric cyclopropanation. These metalloradical catalysts have been shown to be highly effective for asymmetric intermolecular …

Discovery And Characterisation Of A Novel Toxin From Dendroaspis Angusticeps, Named Tx7335, That Activates The Potassium Channel Kcsa, Ivan O. Rivera-Torres, Tony B. Jin, Martine Cadene, Brian T. Chait, Sébastien F. Poget

Publications and Research

Due to their central role in essential physiological processes, potassium channels are common targets for animal toxins. These toxins in turn are of great value as tools for studying channel function and as lead compounds for drug development. Here, we used a direct toxin pull-down assay with immobilised KcsA potassium channel to isolate a novel KcsA-binding toxin (called Tx7335) from eastern green mamba snake (Dendroaspis angusticeps) venom. Sequencing of the toxin by Edman degradation and mass spectrometry revealed a 63 amino acid residue peptide with 4 disulphide bonds that belongs to the three-finger toxin family, but with a unique modification …

The Effect Of Nitrate On The Release Of Glucose Into The Hemolymph Of Crayfish, Procambarus Clarkii, Alec R. Flores, Lee Kats, David Green, Gary Bucciarelli

Seaver College Research And Scholarly Achievement Symposium

Pollutants can change the behaviors of invertebrate stream animals. The level of one common pollutant, nitrate (NO3), has been rising in many local rivers and streams throughout the United States due to increases in anthropogenic sources. Nitrate, heavily regulated for its toxic effects to human health, namely the aiding in the development of cancer, also dangerously affects aquatic species by converting oxygen-carrying pigments to forms that are incapable of carrying oxygen. To understand the stress effects of ambient nitrate exposure on P. clarkii, we collected hemolymph samples from red swamp crayfish (Procambarus clarkii) over a 48-hour period after exposure to …

Biodegradable Copolymers Made With Magnesium Complexes, Reile M. Slattery, Joseph M. Fritsch

Seaver College Research And Scholarly Achievement Symposium

In this study, a bis-ligated magnesium complex was used to initiate the ring opening copolymerization of L-lactide (L-LA) and ϵ-caprolatone (ϵCL) and the isolated polymeric materials were characterized with NMR spectroscopy. First, the simultaneous feeding of both monomers resulted in the synthesis of homopolymer poly-lactic acid (PLA). Polymerization experiments with sequential addition of L-LA and ϵCL yielded surprising results. The ring opening polymerization of ϵCL yielded poly-caprolactone (PCL) which with the addition of L-LA yielded a di-block copolymer of PCL and PLA. The presence of the two homopolymer blocks in the copolymer was identified with ¹³C NMR where …

Optimization Of Mangosteen Dye-Sensitized Solar Cells, Hannah Goemann

Undergraduate Research Symposium 2016

Garcinia mangostana, commonly known as mangosteen, is often referred to as the “queen of fruits” for its delicious flavor and numerous health benefits. Mangosteen has also attracted attention in recent dye-sensitized solar cells (DSSC) studies as the dye extracted from the fruit’s purple-red pericarp has exceeded many natural dyes in DSSC efficiency. In short, this dye is promising for the development of a natural products-based, sustainable DSSC, as it is a highly effective transporter of photoexcited electrons into the solar cell to be converted into electricity. The purpose of this study was to optimize the dye extraction from the mangosteen …

Section Abstracts: Chemistry

Virginia Journal of Science

Abstracts of the Chemistry Section for the 94th Annual Virginia Academy of Science Meeting, May 18-20, 2016, at University of Mary Washington, Fredericksburg, VA.

The Anode Challenge For Lithium-Ion Batteries: A Mechanochemically Synthesized Sn-Fe-C Composite Anode Surpasses Graphitic Carbon, Zhixin Dong, Ruibo Zhang, Dongsheng Ji, Natasha A. Chernova, Khim Karki, Shawn Sallis, Louis Piper, Stanley M. Whittingham

Chemistry Faculty Scholarship

Carbon-based anodes are the key limiting factor in increasing the volumetric capacity of lithium-ion batteries. Tin-based composites are one alternative approach. Nanosized Sn-Fe-C anode materials are mechanochemically synthesized by reducing SnO with Ti in the presence of carbon. The optimum synthesis conditions are found to be 1:0.25:10 for initial ratio of SnO, Ti, and graphite with a total grinding time of 8 h. This optimized composite shows excellent extended cycling at the C/10 rate, delivering a first charge capacity as high as 740 mAh g(-1) and 60% of which still remained after 170 cycles. The calculated volumetric capacity significantly exceeds …

Novel Non-Halogenated Flame Retardant Compounds, Austin Bailey, Charles J. Neef, Time Dawsey

Poster Presentations

Two different boron compounds, bis(tetramethylammonium) decaborate, TMAD, and bis (tetrabutylammonium) decaborate, TBAD were studied as potential replacements for halogenated flame retardants. Current commercially available, halogenated flame retardants are not environmentally friendly and release strong acids upon burning. TMAD and TBAD were combined with triphenylphosphine oxide and cast in polyurethane films at varying levels. These samples were then cut into strips and burned in a UL-94 flame chamber. These samples were also tested via TGA for degradation temperature. These varying levels were tested via several Design of Experiments constructed within Minitab software. Results thus far have shown the potential for these …

Topical Literature Review Of 'Extraction Of Naphthinc Acid From Highly Acidic Oil Using Hydroxide-Based Ionic Liquids', Samiyah Alogayli, Ram Krishna Gupta

Poster Presentations

The isolation and recovery of naphthenic acid from highly acidic model oil was performed using hydroxide-based ionic liquids. An extremely low ionic liquid/oil ratio was used to completely deacidify the model oil. Tetraalkylammonium and tetraalkylphosphonium hydroxide ionic liquids were employed in this study. Tetraalkylammonium-based ionic liquids are more efficient than tetraalkylphosphonium-based ionic liquids. The recyclability of the ionic liquids for the extraction of naphthenic acid was also studied. The regeneration of the extracted naphthenic acid was achieved.

Synthesis, Characterization And Applications Of Naocomposites Of Graphene And Polyaniline, Nada Aljehany, Ram Krishna Gupta

Poster Presentations

Graphene has attracted considerable research interest in different fields of research due to its unique properties such as high electrical conductivity, good mechanical flexibility, and high thermal and chemical stability. These unique properties make them very suitable for energy related applications such as fuel cells, supercapacitors etc. In this work, we have fabricated nanoribbons of graphene oxide by chemical oxidation of multiwall carbon nanotubes. The synthesized graphene nanoribbons were structurally and electrochemically characterized. The shift of (002) peak in graphene nanoribbons compare to MWCNT confirms unzipping of MWCNT and its exfoliation. MWCNT and graphene nanoribbons were electrochemically characterized using cyclic …