Polymeric fibers have been long been used in the medical field to aid in maintaining and improving the quality of life. It is therefore not surprising that fibers play a major role in emerging tissue engineering and regenerative medicine strategies as scaffolds and substrates for the reconstruction of tissues. This dissertation focuses on the development of drug-eluting fibers capable of physical manipulation for surgical reconstructions and the design of macro-level scaffolds for tissue engineering. Wet spinning was selected to fabricate polymeric monofilaments since this process readily lends itself to controlled-release technologies. However, the majority of research involving wet spun fibers focuses on their use as tracks for guiding cell behavior, three-dimensional scaffolds for tissue engineering, or vehicles for localized drug delivery. Little is known about the effects of drug encapsulation on the intrinsic material properties of polymeric fibers. While the incorporation of drugs using the wet spinning technique may at first appear to be a simple process, we discuss how the choice of solvent and drug/polymer interactions determines the molecular morphology of wet spun filaments, which can be used to enhance the final strength of precipitating fibers through solvent-induced crystallization (SINC). The breakdown of the complex wet spinning process contributes to a deeper understanding of the phase separation fundamentals that lead to the gelation and transformation of polymeric streams into solid filaments during immersion precipitation. By better understanding the intricacy of the wet spinning technique, we demonstrate how to engineer multifunctional polymeric fibers, ones that provide structural support and simultaneously deliver of drugs. Our work culminated in the design of surgically implantable drug delivery sutures for cardiovascular applications. We discuss a bench top technique to engineer monofilaments into multifilament yarns so they could be hybridized with existing surgical sutures. The application of multifilament wet spun yarns as drug delivery sutures was evaluated in an established in vivo ovine model for calcification. The principles learned in this work can be used to incorporate hydrophobic/ hydrophilic drugs into polymeric fibers without destroying the mechanical integrity of the filaments for many biomedical and tissue engineering applications. <br/>
Lavin, Danya Marie,
"Bioengineered fibers for localized and sustained drug delivery"
(2012).
Biomedical Engineering Theses and Dissertations.
Brown Digital Repository. Brown University Library.
https://doi.org/10.7301/Z0R20ZNP
