Advanced titanium dioxide-polytetrafluorethylene (TiO2-PTFE) nanocomposite coatings on stainless steel surfaces exhibit significant antibacterial and anti-corrosion properties

Bacterial infection and corrosion are the two of the most significant causes of metallic implant failure. In our study, we innovated a facile two-step approach to synthesising a TiO2-PTFE nanocomposite coating on stainless steel, which endows the implant surface with both antibacterial and anticorrosion properties. By harnessing the adhesion and reactivity of bioinspired polydopamine, the TiO2-PTFE coating was uniformly deposited onto substrates by using a sol-gel dip coating technique. The TiO2-PTFE coating exhibited minimal bacterial adhesion against both Gram-negative Escherichia coli WT F1693 and Gram-positive Staphylococcus auerus F1557. Moreover, it was observed that an increasing TiO2 concentration in the bath enhanced antibacterial activity. Benefiting from the synergistic effect between TiO2 and PTFE, the TiO2-PTFE coating showed improved corrosion resistance in artificial body fluids comparing with the sole TiO2 and PTFE coatings. The TiO2-PTFE coating also demonstrated extraordinary biocompatibility with fibroblast cells in culture, making it a prospective useful strategy to overcome current challenges in the use of metallic implants.