Cytotoxicity Assessment of Corrosion Products of Nitinol Alloys

Nitinol alloys are extensively explored for biomedical applications, such as cardiovascular stents, guide wires, etc. However, continued usage of Nitinol depends on a better understanding of the effects of Ni release from its surface. Ni has been found to have carcinogenic and deleterious effects on the liver and kidney and it also causes necrosis. In this investigation, in vitro cyclic potentiodynamic polarization tests were conducted at 37 °C using Phosphate Buffer Saline (PBS) as an electrolyte. The metal ions in the electrolyte after each test were measured by ICPMS. Endothelial cells were grown in various proportions of resulting electrolyte and cell culture media, and the dosage and time effects of these solutions on cell proliferation and viability were assessed by performing SRB assays. These properties were then correlated with the concentration of the dissolved ions in the electrolyte.