Preparation, characterization, corrosion behavior and cytocompatibility of NiTiO nanosheets hydrothermally synthesized on biomedical NiTi alloy.

The present work reports on the hydrothermal synthesis of nanosheets on biomedical NiTi alloy in pure water. The results show rhombohedral NiTiO nanosheets with thickness of 6 nm can be grown at 200 °C. Hydrothermal treatment enhances the corrosion resistance of the NiTi alloy. 30 min of the treatment significantly reduces Ni ion release, while prolonged hydrothermal time results in increased Ni ion release because of the growth of the nanosheets with large specific surface area. Excitingly, the nanosheets can well support cell growth, which suggests the release amount can be well tolerated. Good corrosion resistance and cytocompatibility combined with large specific surface area render the nanosheets promising as safe and efficient drug carriers of the biomedical NiTi alloy.