Stability and biodegradation of silk fibroin/hyaluronic acid nerve conduits

Abstract

Proteins-polysaccharide scaffolds have been attracted extensive attentions in tissue engineering for decades. However, degradation of these biocomposites are still unknown owe to their difference in hydrophilicity, pore morphology, density and crystallinity, which obviously limits their applications. Here, we designed a silk fibroin/hyaluronic acid (SF/HA) nerve conduit with oriented channels, combining with different components and HA interpenetrating network to improve stability and biodegradation of the conduit. The conduit exhibited well-organized porous structure, remarkable flexibility, water absorption and stability (<8%), determined by morphology and solubility tests. The structure analysis showed that the silk I structures are dominant of the SF/HA conduits. The drug release behavior of the conduits demonstrated gradient release of rhodamine B with an attribute to the oriented channels. Further, by HA skeleton of interpenetrating network, the SF/HA conduits retained conduit and porous morphology in protease XIV solution for 21days. More importantly, the conduits showed good biocompatibility, which are verified by the growth and phenotype of mouse embryonic stem cell. This study broadening the understanding of the biodegradation behavior of protein-polysaccharide biocomposites and provides promising design strategy for nerve conduits.