Injectable chelate-setting hydroxyapatite cement prepared by using chitosan solution: Fabrication, material properties, biocompatibility, and osteoconductivity

摘要

An injectable chelate-setting hydroxyapatite cement (IP6-HAp), formed by chelate-bonding capability of inositol phosphate (IP6), was developed. The effects of ball-milling duration of starting HAp powder and IP6 concentration on the material properties such as injectability and mechanical strength of the cement were examined. The cement powder was prepared by ball-milling the as-synthesized HAp powder for 5min using ZrO2 beads with a diameter of 10mm, followed by another 60min with ZrO2 beads with a diameter of 2mm, and thereafter surface-modified with 5000ppm of IP6 solution. Injectable cement was then fabricated with this HAp powder and 2.5 mass% chitosan as a mixing solution, with a setting time of 36.3 +/- 4.7min and a compressive strength of 19.0 +/- 2.1MPa. The IP6-HAp cements prepared with chitosan showed favorable biocompatibility invitro using an osteoblast cell model, and osteoconductivity invivo using a pig tibia model.