Preparation, Characterization and Biocompatibility of a Silk Fibroin/Bamboo Nanofibrillated Cellulose Composite Hydrogel

To address the limitations of pure silk fibroin (SF) hydrogels, such as poor mechanical strength and rapid degradation, a fully "green" composite hydrogel was developed by integrating bamboo nanofibrillated cellulose (BNC) with SF and crosslinked using the natural agent genipin. The composite formed a stable interpenetrating network, as confirmed by means of SEM and FTIR. This structure led to significantly enhanced mechanical properties (increased storage modulus and pronounced shear-thinning behavior), moderate swelling, and a controllable degradation rate. In vitro biocompatibility assays demonstrated that the BNC-SF hydrogel was non-cytotoxic and excellently supported the adhesion, spreading, and proliferation of L929 fibroblasts. Notably, it exhibited a strong pro-migratory effect in a scratch assay. This work presents a high-performance, injectable scaffold material derived entirely from natural sources, showing great potential for tissue engineering and regenerative medicine applications.