Novel Mesoporous Hydroxyapatite/Chitosan Composite for Bone Repair

The objective of the present investigation was to evaluate the osteogenic properties of mesoporous Hydroxyapatite/Chitosan (HA/CS) composite in vitro and in vivo. HA/CS composite was successfully prepared and synthesized using a freeze-drying method, and then characterized by Scanning Electron Microscope (SEM). Results show that the mesoporous HA/CS composite presents high surface area and porosity. The effects of mesoporous HA/CS on early adhesion, proliferation and differentiation of osteoblast cells in vitro were measured. MTT cytotoxicity test and cell adhesion test show that the composite has good biocompatibility and promotes cell viability and proliferation. In vitro tests show that osteoblast-like cells on the composite surfaces are able to adhere, proliferate, and migrate through the pores. These cells maintained similar expression levels of osteoblastic-associated markers namely Collagen type 1 (COL-I), Bone Morphogenetic Protein 2(BMP-2). Histologic analysis and radiological analysis in vivo also prove that mesoporous HA/CS composite can be used to repair bone defect as a new kind of bone grafting materials.