Polyvinyl alcohol-silk fibroin composite stents: A comprehensive investigation into biocompatibility and mechanical performance

Abstract

Bioresorbable stents (BRS) are manufactured using biodegradable materials. As an alternative to those commonly used in commercial stents, this study explored the development of BRS using polyvinyl alcohol (PVA) and silk fibroin (SF). PVA is a promising material for the fabrication of BRS due to its biocompatibility and mechanical attributes, closely resembling those of aortic vessels. However, its application presents challenges in terms of cell adhesion and proliferation. SF has been extensively studied for its potential to enhance cell adhesion and proliferation, making it a promising biomaterial in the field of medical devices. SF was introduced by dissolving it in a PVA solution or by coating the hydrogel surface with a layer of SF. Initial tests revealed that overnight incubation of fetal bovine serum significantly increased cell viability in hydrogels. Viability assays confirmed that SF substantially improved cell viability compared to PVA alone. The method was extended to fabricate SF-coated stents, which demonstrated robust cell proliferation and improved performance compared to electrospun polycaprolactone scaffolds. In addition, the SF-coated stents displayed an increase in compressive strength, demonstrating improved biocompatibility and mechanical performance. Dynamic mechanical analysis evaluated the positive impact of SF on stent properties at physiological temperatures. The study revealed that PVA-SF stents offer a compromise between biocompatibility, mechanical strength, and elastic recovery, positioning them as a valuable alternative for cardiovascular stent applications. The dual benefits of enhanced biocompatibility and improved mechanical performance make SF-coated stents promising candidates for bioresorbable stent design.