Iimori Yusuke, Kameshima Yoshikazu, Yasumori Atsuo, Okada Kiyoshi
Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, O-okayama, Meguro, Tokyo 152-8552, Japan.
J Mater Sci Mater Med. 2004 Nov;15(11):1247-53.
The effect of the solid/solution (S/S) ratio on apatite formation from CaSiO3 ceramics in simulated body fluid (SBF) was investigated. CaSiO3 ceramics with a Ca/Si ratio of 0.91 were prepared by sintering CaSiO3 powder coprecipitated from ethanol solutions of Ca(NO3)2. 4H2O and Si(OC2H5)4 using NH4OH as the precipitant. These ceramics were reacted with SBF at S/S ratios of 1.0, 2.5 and 8.3 mg/ml at 36.5 degrees C for various times. Formation of apatite was observed at all the S/S ratios after soaking for 1 day. The amount and microstructure of the apatite obtained at a S/S ratio of 8.3 mg/ml, however, differed largely from the product formed at the other two S/S ratios. The apatite formed at S/S = 8.3 mg/ml was of smaller particle size, formed in smaller amount and with less preferred orientation of the (001) of apatite crystals compared with those formed at S/S = 1.0 and 2.5 mg/ml. An increase of Ca and decrease of the P components occurred in the soaked SBF at S/S = 8.3 mg/ml, the changes being much more marked than with the other two S/S ratios. These differences in the concentration changes in SBF at different S/S ratios are attributed to the difference in the apatite formation from the CaSiO3 ceramics.
研究了固/液（S/S）比对CaSiO₃陶瓷在模拟体液（SBF）中磷灰石形成的影响。通过烧结由Ca(NO₃)₂·4H₂O和Si(OC₂H₅)₄的乙醇溶液共沉淀得到的CaSiO₃粉末，并以NH₄OH作为沉淀剂，制备了Ca/Si比为0.91的CaSiO₃陶瓷。这些陶瓷在36.5℃下与SBF以1.0、2.5和8.3mg/ml的S/S比反应不同时间。浸泡1天后，在所有S/S比下均观察到磷灰石的形成。然而，在8.3mg/ml的S/S比下获得的磷灰石的数量和微观结构与在其他两个S/S比下形成的产物有很大差异。与在S/S = 1.0和2.5mg/ml下形成的磷灰石相比，在S/S = 8.3mg/ml下形成的磷灰石粒径更小，形成量更少，且磷灰石晶体（001）的择优取向更少。在S/S = 8.3mg/ml的浸泡SBF中，Ca含量增加而P组分减少，这些变化比其他两个S/S比下更为明显。不同S/S比下SBF中浓度变化的这些差异归因于CaSiO₃陶瓷磷灰石形成的差异。
