[M-IS10] 結晶成長、溶解における界面・ナノ現象

[MIS10-01] リン酸八カルシウム(OCP)ブロックの溶解析出反応による調製とその生物学的評価

*杉浦 悠紀¹、Munar Melvin²、石川 邦夫² (1.産業技術総合研究所、2.九州大学)

キーワード：リン酸カルシウム、人工骨、バイオマテリアル

Although octacalcium phosphate (OCP) powder and a collagen/gelatin composite demonstrate good potential as bone substitutes, an OCP block has not been fabricated to date. In this study, the feasibility of fabricating an OCP block was evaluated through a dissolution-precipitation reaction using a calcium sulfate hemihydrate (CSH) block as a precursor. When the block was immersed in a phosphate salt solution, its composition changed to that of OCP, while its structure was maintained. The diametral tensile strength (DTS) of the OCP block was 1.0 ± 0.2 MPa. The macroporosity and microporosity of the OCP block were 33.4 ± 4.5% and, 69.0 ± 1.6%, respectively. New bone attached well to the OCP block, and this block was partially replaced by bone 2 weeks after implantation. Four weeks after implantation, the surface of the OCP block was nearly covered with new bone and ~30% of the block was replaced by new bone, while no replacement by bone was observed in the case of a hydroxyapatite (HAp) block used as a control. It is concluded that OCP blocks are potentially suitable for their use as artificial bone substitutes.