Physical Sciences and Mathematics Commons^™

Electrospinning Polymer Blends For Biomimetic Scaffolds For Acl Tissue Engineering, Vanessa Lizeth Garcia

Theses and Dissertations - UTB/UTPA

The anterior cruciate ligament (ACL) rupture is one of the most common knee injuries. Current ACL reconstructive strategies consist of using an autograft or an allograft to replace the ligament. However, limitations have led researchers to investigate tissue engineered grafts, known as scaffolds, through electrospinning. Scaffolds made of natural and synthetic polymer blends have the potential to promote cell adhesion while having strong mechanical properties. However, enzymes found in the knee are known to degrade tissues and affect the healing of intra-articular injuries. Results suggest that the natural polymers used in this study modify the thermal properties and tensile strength …

Oxidation Of Dibenzothiophene To Dibenzothiophene Sulfone Using Tungsten (Vi) Oxide, Alejandrina Rivera

Theses and Dissertations - UTB/UTPA

The oxidation of dibenzothiophene (DBT) to dibenzothiophene-sulfone has been considered as an alternate method to remove sulfur from crude oil. This study demonstrates that the oxidative desulfurization (ODS) of DBT to DBT-sulfone occurs using WO3 as a catalyst. WO3 was synthesized and characterized using X-ray diffraction to determine the phase of WO3. Each reaction was refluxed and run for four hours using WO3 as a catalyst, dibenzothiphene, and four different solvents: decahydronapthalene, n-dodecane, decalin, and dodecane. The reactions were performed at temperatures ranging from 120 oC to 150 oC. Aliquots were taken at 30 minutes for up to four hours …

Biological Compatibility And Cytotoxicity Studies Of Hepa-1c1c7, Hepg2, And Mcf-7 Cancer Cell Lines Upon Exposure To Silver, Palladium, And Gold Nanoparticles, M. Esther Salinas

Theses and Dissertations - UTB/UTPA

The field of nanomedicine has recently explored potential applications for cancer treatment ranging from drug delivery methods to cancer imaging techniques. Due to potential risks of nanomaterials affecting non-cancerous cells in the body, in vitro toxicity studies are being conducted. The nanoparticles (NPs) were synthesized from potassium tetrachloroaurate (III) hydrate, potassium tetrabromoaurate (III) dihydrate, potassium tetrachloropalladate (II), and silver nitrate. NPs were synthesized using the Turkevich method or through the sodium borohydride reduction. Particles synthesized using sodium borohydride were stabilized with cetyltrimethylammonium bromide (CTAB). The NPs under investigation were used to treat three cancer cell lines. The treated cells were …

Remediation Of Copper(Ii) And Lead(Ii) From Aqueous Solution Using Engineered Iron Oxide And Manganese Oxide Nanomaterials, Carlos Tamez Jr.

Theses and Dissertations - UTB/UTPA

Nano-sized Fe3O4, Fe2O3, Mn3O4, and MnO2 were synthesized by titration/precipitation and characterized using powder XRD. pH assays determined that optimum binding occurred at pH 4 for Fe3O4 and Fe2O3 and pH 3 for Mn3O4 and MnO2. Maximum adsorption of Cu(II) and Pb(II) occurred within 20 min or less of contact with the nanomaterials. The synthesized nanomaterials showed a binding preference for Pb(II) over Cu(II) at concentrations above 50 ppm. Batch studies also showed no significant reduction in the binding of copper and lead to either Fe3O4, Fe2O3, Mn3O4, or MnO2 in the presence of Na+ , K+ , Mg2+ or …

Reduction Of Nitroaromatic Compounds With Sodium Borohydride Using Transition Metal Sulfides, Samuel Pina Jr.

Theses and Dissertations - UTB/UTPA

The following systems: NaBH4/Fe3S4, NaBH4/Co3S4, NaBH4/NiS, NaBH4/CuS, and NaBH4/ZnS, were investigated for their nitro reducing abilities. Quantitative conversions were observed for the reduction of nitrobenzene with NaBH4/Co3S4 and NaBH4/NiS systems as opposed to only 9% conversion without any catalyst, representing a ten-fold increase in the reducing ability of NaBH4. In ethanol, various nitroaromatic compounds were also successfully reduced in moderate to high yields with 3 molar equivalents of NaBH4, demonstrating a mild alternative for the effective reduction of nitroaromatic compounds to their corresponding aryl amines. Screening of catalysts was carried out using gas chromatography. All products were characterized using 1 …

Oxidation Of Dibenzothiophene To Dibenzothiophene Sulfone Using Tio2, Juan H. Leal

Theses and Dissertations - UTB/UTPA

The oxidation of dibenzothiophene (DBT) to dibenzothiophene-sulfone has been considered as an alternate method to remove sulfur from crude oil. This study demonstrates that the oxidative desulfurization (ODS) of DBT to DBT-sulfone occurs using rutile TiO2 as a catalyst with the aid of O2. In addition, anatase and brookite were synthesized and tested in the reaction. Particle size of the catalysts was calculated and morphology was explored using SEM. A kinetic study was performed to determine the catalytic effect and activation energy of TiO2. The oxidation reaction was carried out by refluxing TiO2 and DBT in decahydronapthalene while flowing O2 …

I. Norbornene As Organocatalyst: Unusual: Amination Ii. Stereoselective Synthesis Of 3, 4 Di-Substituted Β-Lactams; Classical Vs Microwave Method, Ravi Reddaboyna

Theses and Dissertations - UTB/UTPA

I. Amine functionality is important in the preparation of biologically active and industrially useful molecules. Many approaches to form C―N bonds provide access to fine chemical building blocks, pharmaceuticals, agrochemicals, and surfactants. Microwave irradiation is a highly recommended ecofriendly approach for the synthesis of medicinally important compounds. Organic catalysis is important segment in the field of organic chemistry, for the synthesis of many complex molecules by providing a number of advantages.

II. Cancer refers to a large group of diseases characterized by uncontrolled cell multiplication and the ability of these cells to enter other tissues and spread to other parts …

Electrospinning Nanofibers For Controlled Drug Release, Indrani Banik

Theses and Dissertations - UTB/UTPA

Electrospinning is the most widely studied technique for the synthesis of nanofibers. Electrospinning is considered as one of the technologies that can produce nanosized drugs incorporated in polymeric nanofibers. In vitro and in vivo studies have demonstrated that the release rates of drugs from these nanofiber formulations are enhanced compared to those from original drug substance. This technology has the potential for enhancing the oral delivery of poorly soluble drugs [1]. The electrospun mats were made using Polycaprolactone/PCL, Poly(DL-lactide)/PDL 05 and Poly(DL-lactide-co-glycolide)/PLGA. The drugs incorporated in the electrospun fibers were 5-Fluorouracil and Rapamycin. The evidence of the drugs being embedded …