Lysine-functionalized chondroitin sulfate improves the biological properties of collagen/chitosan-based injectable hydrogels.

Novel bioactive collagen/chitosan/lysine-functionalized chondroitin sulfate (CS) injectable hydrogels are presented. The modification of CS with amine groups introduced with lysine moieties (the degree of substitution about 21%) guarantees its covalent binding with the hydrogel network while genipin crosslinking. Both the physicochemical and biological features of developed hydrogels might be adjusted by playing with CS and crosslinking agent concentrations.