Elucidation of surface properties of calcium-ion-implanted titanium in biological systems

用X射线光电子能谱和俄歇电子能谱研究了钙离子注入钛在310K下在硝酸(pH-0.99，0，1和2)和磷酸-柠檬酸缓冲液(pH 5.2和7.2)中的微溶解行为。结果发现，含钙的表面氧化物溶解在溶液中。根据溶解情况，表面氧化物中氧减少，钛增加。此外，羟基自由基数减少，钛中Ti~(2+)~(4+)的比例增加。来源于Ti4+的钙和钛的芯级结合能随溶解而降低。这些变化是由表面氧化物的溶解转化引起的。也就是说，钙溶解了，因此，表面氧化物变成了二氧化钛。表面改性层由三层组成，钙存在于表面改性层的整个深度。钙离子洗脱…通过表面改性层本身的溶解和通过表面改性层的扩散使钙离子进一步溶解到两种溶液中。13EA02：此外，为了比较钙离子(Ca^&lt；2+&gt；)注入钛和钛的表面性质，并探讨钙离子(Ca^&lt；2+&gt；)注入钛的骨传导机制，估算了钙离子(Ca^&lt；2+&gt；)注入钛和钛的羟基自由基量。同时测定了钙离子注入钛和钛表面氧化物的零电荷点。结果表明，Ca~(2+)离子注入钛表面的活性羟基自由基量明显多于钛表面，说明电解液中钙离子注入钛的荷电部位多于钛。金红石(TiO_2)、锐钛矿型(TiO_2)和钙钛矿型(CaTiO_3)的PZC值分别为4.6、5.9和8.1。因此，钙离子注入的钛表面在生物液体中比钛表面更带正电荷，加速了对磷酸根离子的吸附。较少

Microdissolution of calcium ions from calcium-ion-implanted titanium into nitric acid solutions (pH -0.99,0,1, and 2) and phosphate-citric acid buffers (pH 5.2 and 7.2) at 310 K for 10^3-5x10^6s was characterized using X-ray photoelectron spectroscopy and Auger electron spectroscopy. As a result, the surface oxides with calcium were found to dissolve in the solutions. Oxygen decreased and titanium increased in the surface oxide according to the dissolution. In addition, hydroxyl radicals decreased in number and the proportion of Ti^<4+> in titanium increased. Core-level binding energies of calcium, and titanium originating from Ti^<4+> decreased with the dissolution. These changes were caused by the transformation of surface oxide according to the dissolution. That is, calcium dissolved and, consequently, the surface oxide became titanium oxide. The surface-modified layr consisted of three layrs while calcium existed in whole depth of the surface-modified layr. The calcium ions eluted … More into both solutions by the dissolution of the surface-modified layr itself and the dissolution of calcium by the diffusion through the surface-modified layr.13EA02 : In addition, to compare the surface properties of calcium-ion (Ca^<2+>)-implanted titanium with those of titanium and to investigate the mechanism of bone conductivity of Ca^<2+>-implanted titanium, amounts of hydroxyl radical of Ca^<2+>-implanted titanium and titanium were estimated. Also, the point of zero charge of oxide constituting surface oxides of Ca^<2+>-implanted titanium and titanium were determined. Results showed that the amount of active hydroxyl radical on Ca^<2+>-implanted titanium was found to be significantly larger than that on titanium, indicating that the number of electric-charging sites of Ca^<2+>-implanted titanium in electrolyte is more than that of titanium. The pzc values of rutile (TiO_2), anatase (TiO_2), and perovskite (CaTiO_3), were estimated to be 4.6,5.9, and 8.1, respectively. Thus, Ca^<2+>-implanted titanium surface is charged more positively in bioliquid than titanium, accelerating the adsorption of phosphate ions. Less