In situ forming chitosan/hydroxyapatite rods reinforced via genipin crosslinking

Chitosan/hydroxyapatite composite rods are good candidates as temporary mechanical supports in bone regeneration; however the mechanical properties of this kind of materials should be improved. In this work, chitosan/hydroxyapatite composite rods with multilayer structure were reinforced using a bio-crosslinker to improve their mechanical properties and anti-degradation ability. The SEM results revealed that the composite rods had a tree-ring structure. The bending strength and bending modulus of the crosslinked rods could arrive at 161 MPa and 7.2 GPa, respectively, increased by 59.4% and 26.3% compared with uncrosslinked ones (p < 0.05). The enzymatic degradation studies indicated that genipin crosslinking could effectively enhance the biostability of the composite rods. Consequently, genipin-crosslinked chitosan/hydroxyapatite composite rods with excellent mechanical properties would be a novel device used for internal fixation of bone fracture. (C) 2012 Elsevier B.V. All rights reserved.