Self‐Driven Janus Ga/Mg Micromotors for Reducing Deep Bacterial Infection in the Treatment of Periodontitis

Abstract A self‐propulsion Janus gallium (Ga)/magnesium (Mg) bimetallic micromotor is designed with favorable biocompatibility and antimicrobial properties as a therapeutic strategy for periodontitis. The Janus Ga/Mg micromotors are fabricated by microcontact printing technique to asymmetrically modify liquid metallic gallium onto magnesium microspheres. Hydrogen bubbles produced by the magnesium‐water reaction can provide the driving performance of up to 31.03 µm s −1 (pH 6.8), prompting the micromotor to actively breakthrough the biological barrier of saliva and gingival crevice fluid (GCF) into the bottom of periodontal pockets. In addition, the Janus Ga/Mg micromotors are effectively converted by degradation into the built‐in antimicrobial ion Ga(III) to eliminate deep‐seated Porphyromonas gingivalis ( P.gingivalis ), with bactericidal efficiencies of over 99.8%. The developed Janus Ga/Mg micromotors have demonstrated potent antimicrobial and anti‐inflammatory activity both in vitro and in vivo studies. Crucially, it reduces alveolar bone resorption, demonstrating the superior efficacy of liquid metal gallium in treating periodontitis. Therefore, Ga/Mg bimetallic micromotors hold great promise to be an innovative and translational drug delivery system to treat periodontitis or other inflammation‐related diseases in the near future.