Biomedical Engineering and Bioengineering Commons^™

The Development Of A Novel Polymer Based System For Gene Delivery, Anh Van Le

FIU Electronic Theses and Dissertations

Gene therapy involves the use of nucleic acids, either DNA or RNA for the treatment, cure, or prevention of human diseases. Synthetic cationic polymers are promising as a tool for gene delivery because of their high level of design flexibility for biomaterial construction and are capable of binding and condensing DNA through electrostatic interactions.

Our lab has developed a novel polymer (poly (polyethylene glycol-dodecanoate) (PEGD), a polyester of polyethylene glycol (PEG) and dodecanedioic acid (DDA). PEGD is a linear viscous polymer that self-assembles into a vesicle upon immersion in an aqueous solution. A copolymer of dodecanedioc acid and polyethylene glycol …

Cobalt Ferrite Nanoparticles Fabricated Via Co-Precipitation In Air: Overview Of Size Control And Magnetic Properties, Dennis Toledo

FIU Electronic Theses and Dissertations

Cobalt Ferrite has important, size-dependent magnetic properties. Consequently, an overview of particle size is important. Co-precipitation in air was the fabrication method used because it is comparatively simple and safe. The effects of three different reaction times including 1, 2, 3 hour(s) on particle size were compared. Also, the effectiveness of three different capping agents (Oleic Acid, Polyvinylpyrollidone (PVP), and Trisodium Citrate) in reducing aggregation and correspondingly particle size were examined. Using Welch’s analysis of variance (ANOVA) and the relevant post hoc tests, there was no significant difference (p=0.05) between reaction times of 1 hour and 2 hours, but there …

The Microstructure And The Electrochemical Behavior Of Cobalt Chromium Molybdenum Alloys From Retrieved Hip Implants, Christopher P. Emerson

FIU Electronic Theses and Dissertations

Because of their excellent mechanical, tribological, and electrochemical properties, Cobalt Chromium Molybdenum alloys have been used as the material for both the stem and head of modular hip implants. Corrosion is one mechanism by which metal debris, from these implants, is generated, which can lead to adverse events that requires revision surgery. Manufacturing process such as wrought, as-cast, and powder metallurgy influences the microstructure, material properties, and performance of these implants

The current research focuses on analyzing the microstructure of CoCrMo alloys from retrieved hip implants with optical and scanning electron microscopy. Additionally, energy disperse spectroscopy was utilized to determine …

In-Vivo Corrosion And Fretting Of Modular Ti-6al-4v/Co-Cr-Mo Hip Prostheses: The Influence Of Microstructure And Design Parameters, Jose Luis Gonzalez Jr

FIU Electronic Theses and Dissertations

The purpose of this study was to evaluate the incidence of corrosion and fretting in 48 retrieved titanium-6aluminum-4vanadium and/or cobalt-chromium-molybdenum modular total hip prosthesis with respect to alloy material microstructure and design parameters. The results revealed vastly different performance results for the wide array of microstructures examined. Severe corrosion/fretting was seen in 100% of as-cast, 24% of low carbon wrought, 9% of high carbon wrought and 5% of solution heat treated cobalt-chrome. Severe corrosion/fretting was observed in 60% of Ti-6Al-4V components. Design features which allow for fluid entry and stagnation, amplification of contact pressure and/or increased micromotion were also shown …