Self-Sacrificial Antibacterial Coating with Photothermal Response for Inhibiting Implant Infection

Currently, titanium (Ti) metal implantation has become one of the hottest surgeries. However, implant-related infections caused by drug-resistant bacteria are a serious problem facing clinical treatment. Therefore, modifying the surface of the implant to endow it with the ability to destroy the biofilm on the implant surface and to kill bacteria at the infection site is an effective strategy for controlling drug-resistant bacterial infection on the implant surface. In this work, a Ti implant (M-Ti) was achieved by preparing two layers of coating on the surface of Ti. Specifically, the first coating comprised vancomycin (Van) and zeolitic imidazolate framework-8 (ZIF-8) nanoparticles. Then, the second self-sacrificial coating with photothermal response based on hexadecanol and Cu 2 O nanoparticles was encapsulated on the first coating. After that, the M-Ti implant was applied to inhibit implant-related infection caused by methicillin-resistant Staphylococci aureus (MRSA). The results indicated that under the irradiation of a near-infrared region 2 (NIR-II) laser, the self-sacrificial coating could disintegrate the mature biofilm through mechanical stress generated by phase transition of hexadecanol. The Van released from the first coating could kill bacteria synergistically with photothermal therapy. The in vitro experimental results showed that the killing efficiency of M-Ti against MRSA reached over 99.99%. The implant-related infection model in mice implied that M-Ti was able to effectively destroy the biofilm and kill bacteria, thereby hindering the occurrence of inflammatory reactions and accelerating the integration between tissues and implant. The advantages of facile preparation and favorable overall performance predicated the tremendous potential application of M-Ti in the fields of orthopedics, dentistry, and plastic surgery.