Biomimetic control on ceramics surfaces by polarization induction

电极化诱导羟基磷灰石（HAp）陶瓷表面电荷改变有机化合物的构象。烧结后的HAp陶瓷在400℃的直流电场中被电极化。在苯基三氯硅烷（PTCS）的甲苯溶液中沉积HAp陶瓷上的有机层。接触角测量和红外光谱分析结果明确了含PTCS碎片的有机层。在带正电的表面上获得的层的数量与带负电和非极化表面上的层的数量相同。从Ca2p和Si2p的深度分布来看，非极化表面的层厚比极化表面的层薄。虽然PTCS溶液在非极化HAp表面制备的沉积应该是包含苯基硅键的自组装层，但极化HAp表面的层聚集不规则。因此，极化诱导的HAp陶瓷表面电荷改变了非水体系中与有机化合物的静电相互作用。

The conformation of organic compound deposited on hydroxyapatite (HAp) ceramics was manipulated by their surface charge induced by electrical polarization. The sintered HAp ceramics were electrically polarized in a d.c. field at 4O0℃. The organic layers on the HAp ceramics were deposited from a toluene solution of phenyltrichlorosilane (PTCS). The results of contact angle measurements and IR spectroscopy clarified the organic layer containing the fragments of PTCS.The amount of the obtained layer on the positively charged surface was those on the negatively charged and non-polarized surfaces. The thickness of the layer on the non-polarized surfaces was thinner than those on the polarized surfaces, based on the depth profiles of Ca2p and Si2p. Although the deposition prepared on the non-polarized HAp surfaces from the PTCS solution was supposed to be a self-assembled layer including of phenyl-Si bond, the layers on the polarized HAp were aggregated irregularly. Consequently, the HAp ceramic surface charge induced by the polarization altered the electrostatic interaction to the organic compounds in non-aqueous system.