Nanocomposite Coatings on Biomedical Grade Stainless Steel for Improved Corrosion Resistance and Biocompatibility

The 316 L stainless steel is one of the most commonly available commercial implant materials with a few limitations in its ease of biocompatibility and long-standing performance. Hence, porous TiO2/ZrO2 nanocomposite coated over 316 L stainless steels was studied for their enhanced performance in terms of its biocompatibility and corrosion resistance, following a sol–gel process via dip-coating technique. The surface composition and porosity texture was studied to be uniform on the substrate. Biocompatibility studies on the TiO2/ZrO2 nanocomposite coatings were investigated by placing the coated substrate in a simulated body fluid (SBF). The immersion procedure resulted in the complete coverage of the TiO2/ZrO2 nanocomposite (coated on the surface of 316 L stainless steel) with the growth of a one-dimensional (1D) rod-like carbonate-containing apatite. The TiO2/ZrO2 nanocomposite coated specimens showed a higher corrosion resistance in the SBF solution with an enhanced biocompatibility, surpassing the performance of the pure oxide coatings. The cell viability of TiO2/ZrO2 nanocomposite coated implant surface was examined under human dermal fibroblasts culture, and it was observed that the composite coating enhances the proliferation through effective cellular attachment compared to pristine 316 L SS surface.