In vitro cytotoxicity and corrosion studies of some copper base shape memory alloys

Abstract

In recent times Cu-based shape memory alloys are being used more extensively in many engineering applications due to their ease of production and processing and lower cost. But Cu-based alloys have not been found suitable for medical applications due to the toxic effects arising from the release of Cu ions into the body. The present work explores the feasibility of using Cu-based shape memory alloys (Cu-Al-Mn and Cu-Al-Ni) for biomedical applications. The toxicity level of the alloys was measured by cell culture (24 h) studies using SaOS-2 osteoblast and L6 myoblast cells, and other studies by using L6 myoblast cells (48 h and 72 h). Moreover, surface energy evaluation and corrosion studies were carried out in a simulated uterine fluid. An E-SEM was used to study the adhesion capability of the cells. The surface energy studies were carried out to assess the effect of cell adhesion on the alloy surface, while the corrosion studies to validate the cell culture results. Attempts were made to analyze the cause of toxic effects by analysing the polarization curves, results of SEM/EDAX and spectroscopy (ICP-OES) after corrosion studies in a simulated uterine fluid. It was found that Cu-Al-Mn alloys exhibit much better cell compatibility as compared to Cu-Al-Ni alloys.