In vitro and in vivo antibacterial activity of graphene oxide‐modified porous TiO ₂ coatings under 808‐nm light irradiation

Abstract Bio‐inertness and post‐surgery infection on titanium (Ti) are the main causes of failure of biomedical implants in vivo. Near‐infrared (NIR) photoactivated antibacterial therapy including photothermal and photodynamic therapies has attracted increasing attention due to the high bactericidal efficiency and little side effects. Although micro‐arc oxidation (MAO) is an effective method to improve the biological activity of Ti implants, the porous TiO 2 coatings prepared by MAO do not respond to near‐infrared (NIR) light to kill bacteria by the photothermal and photodynamic effects. In this work, graphene oxide (GO)‐modified TiO 2 coatings (TiO 2 /GO) are prepared on Ti to improve the photothermal and photodynamic ability of the MAO coatings. The TiO 2 /GO coatings exhibit excellent antibacterial activity both in vitro and in vivo against Streptococcus mutans ( S. mutans ) under 808‐nm NIR light irradiation due to the synergistic effects rendered by hyperthermia and reactive oxygen species (ROS). The NIR light‐responsive antibacterial MAO coatings have large potential in combating implant‐associated infections in clinical applications.