Characterization of a Water-Dispersed Biodegradable Polyurethane-Silk Composite Sponge Using C Solid-State Nuclear Magnetic Resonance as Coating Material for Silk Vascular Grafts with Small Diameters.

Recently, silk fibroin (SF) has been shown to be a suitable material for vascular prostheses for small arteries. In this study, we developed a softer SF graft by coating water-dispersed biodegradable polyurethane (PU) based on polycaprolactone and an SF composite sponge on the knitted SF vascular graft. Three kinds of C solid-state nuclear magnetic resonance (NMR), namely carbon-13 (C) cross-polarization/magic angle spinning (MAS), C dipolar decoupled MAS, and C refocused insensitive nuclei enhanced by polarization transfer (r-INEPT) NMR, were used to characterize the PU-SF coating sponge.