Facile Construction of Chitin/Graphene Nanocomposite Sponges for Efficient Hemostasis

Polysaccharide chitin is a good candidate for hemostasis, while its hemostatic efficacy is limited due to insufficient adsorption and activation of coagulation factors. Herein, the few-layer graphene nanosheets were facilely incorporated into chitin through ball-milling the mixture of graphite and chitin to fabricate the chitin/graphene nanocomposite, which was used to construct the nanocomposite sponges. The in vitro whole blood clotting test indicates that the addition of graphene in the chitin sponge greatly promoted the coagulation process. In the nanocomposite sponge, the three-dimensional networks induced the erythrocyte adsorption, and the dispersed graphene nanosheets further promoted their aggregation for fast coagulation. With these advantages, the chitin/graphene nanocomposite sponge reduced 62% of the blood loss at a shorter hemostatic time (76 s) in the rat liver injury model, which was significantly better than the commercial polyvinyl formal sponge. Furthermore, the subcutaneously implanted nanocomposite sponge exhibited the distinct advantage of chitin with good biocompatibility and effective biodegradability. Our work demonstrates a facile strategy to construct the effective chitin-based hemostatic sponges simultaneously featuring fast aggregation of erythrocytes and excellent biocompatibility.