Development of Natural Type Hydroxyapatite-Collagen Composite

传统上，羟基磷灰石烧结的目标是由于与骨组织的化学结合而形成坚硬、稳定的磷灰石。然而，由于弹性模量的差异，烧结羟基磷灰石与骨的直接结合在严重的重复载荷下可能会像金属的骨整合一样容易被破坏。因此，开发坚硬、稳定的羟基磷灰石就像在生物惰性金属的情况下用于生物力学替代物一样没有意义。缺钙羟基磷灰石的烧结已经有报道，它在缺钙部位结合水，并在300 ℃和600 MPa的压力下烧结成完全致密的物体。在水相中胶原存在的条件下，我们尝试用磷酸水溶液和氢氧化钙悬浮液反应合成羟基磷灰石。将稀释的胶原蛋白溶液与磷酸水溶液混合，并缓慢倒入氢氧化钙溶液中， ...更多信息 悬浮的水相。在由此形成的母液中没有发现胶原。发现溶液中的所有胶原蛋白都聚集在沉淀物中。将500克市售胶原蛋白溶液稀释至8升，并与0.6摩尔磷酸混合。将CaO粉碎成细粉并与水混合。混合由此形成的Ca（OH）水悬浮液，并缓慢加入胶原-磷酸混合溶液。过滤沉淀物并部分干燥直至形成合适的水含量。然后，它被安装在一个金属胶囊里。密封舱被抽空并通过焊接密封。在200 MPa、40 ℃下保持8小时，得到的磷灰石-胶原复合材料的密度为1.75g/ml，杨氏模量为2GPa，压缩强度为6.5MPa。样品可以用刀切割，并且在水中稳定。这种类型的复合物的物理性质可以根据组成和处理条件而改变。将样品植入狗的chandrichthies（鲨鱼）中并进行组织学评价。利用新开发的生物材料，进行了实验进化研究。成功地进行了鲨鱼与两栖类异种移植。通过研究发现，原型脊椎动物的免疫系统与高等脊椎动物的胚胎一样处于耐受状态。少

Conventionally, hydroxyapatite sintering has been aimed at stiff, stable apatite due to chemical bonding with osseous tissue. However, direct bonding of sintered hydroxyapatite with bone may easily be destroyed under severe repeated loading just like osseointegration of metal because of differences in elastic moduli from each other. Therefore, development of stiff, stable hydroxyapatite makes no sense just as in the case of bioinert metal for biomechanical substitution.Sintering of calcium-deficient hydroxyapatite has already been reported, which bonded water at the calcium-deficient site, and was sintered up to fully dense bodies at 300ﾟC under a pressure of 600MPa. In the presence of collagen in an aqueous phase, we tried tosynthesize the hydroxyapatite by means of reaction between an aqueous solution of phosphoric acid and a calcium-hydroxide suspension. A diluted collagen solution was mixed with an aqueous solution of phosphoric acid and was poured slowly into a calcium-hydroxide s … More uspended aqueous phase. No collagen was found in the mother liquid thus formed. All collagen in the solution was found to be collecting in the precipitate. Five hundred grams of commercially available collagen solution was diluted up to 8 liters and mixed with 0.6mole of phosphoric acid. The CaO was crushed into fine powder and mixed with water. The Ca (OH) aqueous suspension thus formed was mixed, and the collagen-phosphoric acid mixed solution was added slowly. The precipitate was filtered and partly dried until suitable water content formed. Then, it was mounted in a metal capsule. The capsule was evacuated and sealed by welding. It was thin kept for 8 hrs at 200 MPa at 40ﾟC.The resulting apatite-collagen composite was 1.75g/ml in density, 2GPa in Young's modulus, and 6.5MPa in compression strength. The specimen could be cut by a knife, and was stable against immersion in water. The physical property of this type of complex may change according to composition and treating conditions. The sample was implanted in dogs chandrichthies (shark) and histologically evalutated. Using newly development biomaterials, experimental evolutionary study is carried out. Xenotransplantations between shark and amphibian are successfully carried out. From this research implant fact is discovered that in archetype vertebrates immune system is in tolerance just like embryo of higher vertebrates. Less