Effect of Ternary Addition on Cytotoxicity of Cu-Based Shape Memory Alloys

Ni-Ti shape memory alloys are widely accepted as implants because of  their excellent biocompatibility and high superelasticity. Even though Cu-based shape memory alloys are comparable to NiTi SMAs in terms of superelasticity, they have not been accepted by the global medical industry due to paucity of information on their toxic behaviour. Researchers have studied toxicity of Cu-Al-Ni alloys using rat cells (L929 fibroblast cell lines). In the present work, an attempt has been made to investigate the cytotoxicity of Cu-Al-X(Mn, Ni, Ag)  shape memory alloys in L6 fibroblast cell lines. High purity copper, aluminium, nickel, silver and manganese taken in appropriate quantities were melted together to yield alloy ingots that adhere to the desired compositions for good shape memory effect. . Samples were cut from the ingots, homogenized at 850°C in an argon atmosphere and quenched in water.  The as-quenched samples were then rolled at 850°C to produce sheets of 1mm thickness. Disc-shaped samples (~9mm) were cut from the rolled sheets for cell culture studies. MTT assay was done to find the number of live cells and dead cells in the culture plate. CuAlMn alloys showed lower cytotoxicity compared to CuAlAg and CuAlNi alloys.