Graphene Oxide/Ferroferric Oxide Composite Coating with Synergistic Augmented Chemodynamic Therapy for the Elimination of Implant-Associated Infection

Titanium (Ti) stands as a widely used orthopedic implant material, but implant-associated infection remains a formidable and critical contributor to implant failure in clinical practice. To address this intractable challenge, we reported a composite coating comprised of graphene oxide (GO) and ferroferric oxide (Fe3O4) on the Ti matrix surface (denoted as Ti/GO/Fe3O4), which showed synergistically augmented chemodynamic therapy against implant-associated infection. Specifically, the surface hydrophilic and negatively charged coating could physically deter initial bacterial adherence. Moreover, the GO sheet, with sharp-edged architecture, mediated the mechanical nanoknife effect, leading to the physical cleavage of the bacterial membrane. With the help of multienzyme-mimetic activity, GO/Fe3O4 acquired a moderate ROS burst and sustained a relatively high ROS level by glutathione consumption, causing chemical, ferroptosis-like bacterial death. Both in vitro and in vivo assays confirmed that the biocompatible and multifunctional coating was effective in preventing implant-associated infection, which could speed up the implant-tissue integration process. Such work would offer a technical route to design a nonantibiotic, biosafe, and multimodal infection-resistant implant device, which implies considerable potential in clinical application.