Effect of Viscosities on the Surface Morphology and Crystallographic Properties of Hydroxyapatite Coated Titanium Dioxide Nanotubes.

Hydroxyapatite (HA) coating on biomaterials is crucial for bone growth. TiO2 naotubes having a larger specific area can also improve an osseointegration. In this study, anodized TiO2 nanotubes were coated with HA using sol-gel method with different viscosities of solution. Morphological characterization and crystal structures of the coated specimens were measured via field emission scanning electron microscope, transmission electron microscope, X-ray diffractometer, and fourier transforrm infrared spectroscopy. Nanosized hydroxyapatite particles were observed with sol viscosities at 1.95 cP and 0.94 cP inside the TiO2 nanotubes. When coated with the lower viscosity of solution, the TiO2 nanotubes were clearly observed. The crystallinity of HA increased as the temperature of heat treatment increased. The HA phase on the specimen was identified by PO4(3-) and OH-ion peaks in FT-IR spectra.