Cytotoxicity of Ni from Surface-Treated Porous Nitinol (PNT) on Osteoblast Cells.

The leaching of nickel from the surface of porous Nitinol (PNT) is mainly dependent on its surface characteristics, which can be controlled by appropriate surface treatments. In this investigation, PNT was subjected to two surface treatments, namely, water-boiling and dry-heating passivations. Phosphate buffer saline (PBS) solutions obtained from cyclic potentiodynamic polarization tests on PNT were employed to assess the cytotoxicity of Ni contained therein on osteoblast cells by Sulforhodamine B (SRB) assay. In addition, similar concentrations of Ni were added exogenously to cell culture media to determine cytotoxic effects on osteoblast cells. The morphologies of the untreated and the surface-treated PNTs were examined using SEM and AFM. Furthermore, growth of human osteoblast cells was observed on the PNT surfaces.