Application of Phosphate Based Inorganic Compounds to Biomedical, Life, and Environmental Materials

我们一直在研究磷酸盐无机化合物在生物医学、生命和环境材料中的应用。本研究的部分成果如下：(1)添加聚丙烯酰胺、聚甲基丙烯酸甲酯、丙烯酰胺单体制备磷酸钙水硬硬化体。上述添加剂在室温下磷酸钙的水解显着，并在80℃以上加速。磷酸钙骨水泥采用羟基磷灰石、α-Ca_3(PO_4)_2、β-Ca_3(PO_4)_2、无定形磷酸钙的热分解产物。发现所获得的磷酸钙硬化体的堆积密度约为1.7，弯曲强度为11-12 MPa，比不添加聚合物所获得的磷酸钙硬化体增加了一倍。（2）我们发现，在极化陶瓷和羟基磷灰石涂层上的模拟体液溶液中，骨状晶体生长的加速和减速取决于电极化条件。晶体生长取决于直流场强、温度和极化时间。在带负电的表面上观察到加速的晶体生长，而在带正电的表面上从未发生晶体生长。分析结果表明形成了部分碳酸化羟基磷灰石钙的骨状晶体。目前的结果预计将极大地促进植入材料仿生 HAp 涂层方法的发展。

We have been investigated on application of phosphate-based inorganic compounds to biomedical, life, and environmental materials. Some results of this research are shown below.(1) Preparation of hydraulic hardened bodies of calcium phosphates was carried out adding polyacrylamide, polymethylmetacrylate, and monomer of acrylamide. Hydrolysis of calcium phosphates was remarkably by the above additives at room temperature and accelerated above 80ﾟC.Thermal decomposition products of hydroxyapatite, alpha-Ca_3(PO_4)_2, beta-Ca_3(PO_4)_2, and amorphous calcium phosphate were used as calcium phosphate cements. The calcium phosphate hardened bodies obtained were found to be about 1.7 in bulk density and 11-12 MPa in bending strength, which was doubled compared with that obtained on no addition of polymers.(2) We have discovered the acceleration and deceleration of bone-like crystal growth in simulated body fluid solution on polarized ceramics and coatings of hydroxyapatite, depending on the electric polarization conditions. The crystal growth was dependent upon the dc field strength, temperature, and time for polarization. The accelerated crystal growth was observed on negatively charged surfaces, whereas no crystal growth ever took place on the positively charged surface. The analytical results indicate the formation of bone-like crystals of partially carbonated calcium hydroxyapatite. The present result is expected to greatly contribute to the development of biomimetic HAp coating methods on implant materials.