Chemically Reprogramming Liquid Metals With Polyphenols for a Self‐Reinforcing Assault on Biofilms

The physical eradication of bacterial biofilms is fundamentally limited by rapid post‐treatment regeneration. A strategy that integrates physical destruction with biological suppression is therefore highly coveted. Herein, we introduce a strategy to chemically reprogram magnetic liquid metals (LMs) into intelligent antibiofilm nanocomposites. Through a one‐step metal‐phenolic coordination, we coat the LM with a natural polyphenol (baicalin, BA), creating a nanoplatform (MBA) that executes a synergistic “destroy‐and‐pacify” mission. This design establishes a self‐reinforcing loop: magnetic actuation provides the mechanical force to breach the biofilm matrix, enhancing the penetration of the BA coating. Concurrently, the BA‐mediated inhibition of quorum sensing and EPS synthesis pre‐weakens the biofilm, making it more susceptible to physical ablation. This reciprocal potentiation leads to exceptional efficacy, more than doubling the clearance efficiency of mature P. aeruginosa biofilms on implants in a murine model and achieving a level of eradication unattainable by monotherapies. This work establishes a new paradigm for designing smart theranostic microrobots, paving the way for programmable platforms to tackle complex biological barriers.