Bactericidal and biocompatible properties of TiN/Ag multilayered films by ion beam assisted deposition

Nanoscale TiN/Ag multilayered films of thickness 500 nm were synthesized on AISI317 stainless steel by ion beam assisted deposition (IBAD) with the modulation period of 4, 5, 6, 7.5, and 12 nm. The bactericidal and biocompatible properties of TiN/Ag multilayered films were investigated through Gram negative E. coli bacteria and L929 cells (mice fibroblast) as well as human umbilical vein endothelial cells (HUVEC). The results show that the TiN/Ag multilayered films with the modulation period of 7.5 nm possess the strongest bactericidal property. The cytotoxicity grade of TiN/Ag multilayered coating with the modulation periods of 7.5 nm, 12 nm is in 0-1 scope, which indicates this film has no cytotoxicity to L929. HUVEC on TiN/Ag multilayered film grows well and shows good cellularity. Auger electronic spectroscopy reveals the relationship between the structure of TiN/Ag multilayered film and the biomedical properties.