Light-responsive Au/TiO₂/PDA coating enhances the antibacterial performance of titanium implants

Area of Science:

• Biomaterials Science
• Nanotechnology
• Infectious Diseases

Background:

• Implant-associated infections are a major cause of titanium implant failure.
• Photocatalytic materials, like titanium dioxide, generate reactive oxygen species (ROS) to combat bacteria.
• The wide bandgap of titanium dioxide limits its efficacy to ultraviolet light.

Purpose of the Study:

• To develop a light-responsive antibacterial coating for titanium substrates.
• To extend the photocatalytic activity of titanium dioxide to visible and near-infrared ranges.
• To create a coating with enhanced antibacterial properties and biocompatibility for medical implants.

Main Methods:

• Dopamine-mediated polymerization was used to create a coating on titanium substrates.
• Gold nanoparticles (Au NPs) and titanium dioxide quantum dots (TiO2 QDs) were incorporated into the coating.
• The antibacterial efficacy and biocompatibility of the Au/TiO2/PDA coating were evaluated under simulated solar irradiation.

Main Results:

• The Au/TiO2/PDA coating exhibited potent antibacterial activity against Staphylococcus aureus and Escherichia coli.
• The antibacterial effect was attributed to the synergistic action of ROS generation and localized hyperthermia.
• The coating demonstrated excellent biocompatibility with the titanium substrate.

Conclusions:

• The developed light-responsive coating significantly enhances the antibacterial properties of titanium implants.
• This facile and scalable surface modification strategy shows great potential for preventing implant-related infections.
• The Au/TiO2/PDA coating offers a promising solution for improving the safety and longevity of medical implants.