Subject Area

Bioengineering and Biomedical Engineering, Chemistry, Materials Science, Physical Sciences

Abstract

I. Two different series of non–degradable polysiloxane networks were prepared for the encapsulation and controlled release of a small molecule agent. For the first series, hydrosilylation was utilized to prepare networks of varying crosslink densities, as determined from swelling studies, from vinyl terminated and silylhydride functional poly(dimethyl)siloxanes. For the second series, the thiol-ene reaction was utilized to prepare networks of varying crosslink densities, as determined from swelling studies, from vinyl terminated and mercaptopropyl functional poly(dimethyl)siloxanes. Nile red dye was used as an encapsulated agent and dye release from each series of networks was measured using UV–vis spectroscopy to determine controllability of encapsulated agent release from each network series through crosslink densities and thioether polar group concentration. In addition, the networks were analyzed via dielectric analysis to determine network polarity and its effect on dye release. Multi-layered network systems were also prepared to study the ability of producing delivery devices capable of utilizing varying crosslink densities to physically affect the directionality and amount of encapsulated agent release.

II. A series of additive free, hydrolytically degradable furyl–maleimide networks were prepared for the encapsulation and controlled release of a small molecule agent. The Diels–Alder vii reaction was utilized to prepare networks with varying degradation rates using a tri–functional furyl silane, with either a bi-functional maleimide silane, or a bi-functional maleimide disiloxane. The thermal characteristics of the networks were studied through Differential Scanning Calorimetry to determine crosslinking reaction completion and material characteristics. Degradation rates for the networks were determined through mass loss studies in buffered saline at 37 °C. Disodium fluorescein dye was used as an encapsulated agent and dye release from the networks was measured using UV–vis spectroscopy. The primary product of degradation for the networks was characterized by 1H NMR spectroscopy and synthesized through Diels–Alder chemistry. A toxicity study of the synthesized degradation product was performed via an MTT assay to determine its cellular toxicity.

Degree Date

Spring 5-16-2020

Document Type

Dissertation

Degree Name

Ph.D.

Department

Chemistry

Advisor

David Y. Son

Number of Pages

246

Format

.pdf

Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License

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