Hanawa T, Ota M
Department of Dental Materials and Engineering, Hokkaido University School of Dentistry, Sapporo, Japan.
Biomaterials. 1991 Oct;12(8):767-74. doi: 10.1016/0142-9612(91)90028-9.
Surface films formed on titanium specimens immersed in electrolyte solutions (pH 4.5, 5.2, 7.4) at 37 degrees C for 1 h, 1 d, 30 d, and/or 60 d, were characterized using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared reflection absorption spectroscopy (FTIR-RAS) to understand the reaction between titanium and inorganic ions. For comparison, the surface of Ti-6AI-4V and Ti-50Ni were also characterized. XPS data revealed that calcium phosphates were naturally formed on these specimens. In particular, compared with the calcium phosphates formed on the titanium alloys, the calcium phosphate formed on titanium immersed for 30 d in the solution with pH 7.4 was more like hydroxyapatite. The compositions of the calcium phosphates formed on the specimens changed with the immersion time and the pH value of the solution. The spectrum obtained using FTIR-RAS from titanium immersed in the solution with pH 7.4 for 60 d was similar to that obtained from carbonate-containing hydroxyapatite. The results indicate that a calcium phosphate similar to apatite is naturally formed on titanium in a neutral electrolyte solution in 30 d. In regard to titanium being a biomaterial, we found this to be an intriguing property. It is possible that this calcium phosphate is responsible for the resulting biocompatibility of titanium.
将钛样品浸入37摄氏度的电解质溶液（pH值分别为4.5、5.2、7.4）中1小时、1天、30天和/或60天，形成表面膜，使用X射线光电子能谱（XPS）和傅里叶变换红外反射吸收光谱（FTIR-RAS）对其进行表征，以了解钛与无机离子之间的反应。作为对比，还对Ti-6AI-4V和Ti-50Ni的表面进行了表征。XPS数据表明，这些样品上自然形成了磷酸钙。特别是，与在钛合金上形成的磷酸钙相比，在pH值为7.4的溶液中浸泡30天的钛表面形成的磷酸钙更类似于羟基磷灰石。样品上形成的磷酸钙的成分随浸泡时间和溶液的pH值而变化。用FTIR-RAS从在pH值为7.4的溶液中浸泡60天的钛上获得的光谱与从含碳酸盐的羟基磷灰石上获得的光谱相似。结果表明，在中性电解质溶液中，30天内钛表面自然形成了类似于磷灰石的磷酸钙。考虑到钛作为一种生物材料，我们发现这是一个有趣的特性。这种磷酸钙可能是钛产生生物相容性的原因。
