Preparation and bioactivity of embedded-style hydroxyapatite--titania nanotube arrays.

Embedded-style hydroxyapatite-titania nanotube arrays were successfully prepared by anodic oxidation of titanium substrate and centrifugal filling hydroxyapatite precursor sol into hollow nanotubes. The morphology, microstructure and thermal stability of the samples were characterized by X-ray diffraction, environmental scanning electron microscopy, and energy dispersive X-ray analysis. The results show that the structure of titania nanotube arrays is stable at 500 °C or below, and the crystallized hydroxyapatite could be formed from hydroxyapatite precursor sol after calcining at 500 °C for 4 h. The optimum calcining temperature for this material is 500 °C. An obvious apatite layer formed on the surface of the embedded-style material after soaking in simulated body fluid for 5 days, indicating that the material possesses a good in vitro apatite forming ability on its surface. [ABSTRACT FROM AUTHOR]