One‐End‐Opened Yolk–Shell Copper Single‐Atom Microrobots for Enhanced Penetration and Eradication of Bacterial Biofilms

Abstract Single‐atom catalysts (SACs) hold remarkable potential for antibacterial and multidrug‐resistant Staphylococcus aureus (MRSA) biofilm eradication, but passive diffusion often restricts their effectiveness. In contrast, microrobots can harness various energy sources for highly autonomous movement. Herein, a one‐end‐opened yolk–shell microrobot with Cu single atoms anchored on carbon nitride (Y‐CuSA/CN) is designed to enhance MRSA biofilm penetration and antibacterial effects. The Y‐CuSA/CN microrobot achieves single‐atom‐driven diffusion propulsion by generating an H 2 O 2 gradient via a Fenton‐like reaction. Furthermore, UV‐LED light (365 nm) excitation produces photogenerated electrons, which promotes the valence cycling of Cu single‐atom and reacts with H 2 O 2 , thereby further boosting the microrobot's mobility and catalytic activity. The Y‐CuSA/CN microrobot exhibits vigorous autonomous movement with a velocity of 17.2 µm s −1 and a diffusion rate of 7.2 µm 2 s −1 , significantly enhancing its penetration into MRSA bacterial biofilms. During the Y‐CuSA/CN microrobot's motion, reactive oxygen species (·OH, ·O 2 − , and 1 O 2 ) are released via catalytic oxidation. In vitro and in vivo experiments demonstrate that the Y‐CuSA/CN microrobot effectively eradicates biofilms and significantly promotes wound healing in infected mice. This study presents an efficient strategy for eradicating MRSA biofilm and highlights the potential of SACs in developing advanced microrobots for biomedical applications.