Abstract
Implant-associated infections (IAIs), particularly those caused by methicillin-resistant Staphylococcus aureus (MRSA), remain a major clinical challenge that frequently leads to implant failure. Here, we report an alternating magnetic field (AMF)-activatable titanium implant (Ti-MgZnCa) that integrates spatiotemporally programmable antibacterial therapy with intrinsic, sustained antimicrobial defense, addressing key limitations of systemic antibiotics including insufficient local bioavailability, resistance development, and systemic side effects. Under AMF stimulation, the Ti-MgZnCa displays a magnetothermal effect that accelerates amorphous coating degradation, promotes rapid Zn2+/Mg2+ release, and facilitates efficient singlet oxygen (¹O₂) generation, thereby achieving potent short‑term antibacterial outcomes (99.74% against MRSA within 15 min). After activation, controlled surface evolution produces a microporous hydrophilic surface that facilitates post‑antibacterial cell adhesion and proliferation. In an acute infection model of rat tibial implants, Ti‑MgZnCa achieves an antibacterial rate of 98.59% after 15 min of AMF treatment and 99.99% after 7 days, without detectable systemic inflammation as confirmed by complete blood counts. This AMF‑responsive implant combines intrinsic antibacterial activity, on‑demand high‑efficiency bactericidal function, and favorable biocompatibility, offering a promising strategy for infection-resistant orthopedic implants and supporting its potential for clinical applications.