Metal organic framework-loaded biohybrid magnetic microrobots for enhanced antibacterial treatment

Overused antibiotics has caused a serious threat of pathogen resistance, and it is urgent to develop drug-free strategies for efficient bacterial eradication. Metal organic frameworks (MOFs) can gradually release metal ions to kill bacteria, yet it is challenging for them to achieve good dispersion and targeted mobility with enhanced antibacterial efficiency. Herein, we developed ZIF-8 loaded biohybrid magnetic microrobots using chlorella cells as biotemplates for the first time, and demonstrated their excellent antibacterial performance. In this approach, Fe3O4 nanoparticles were deposited inside chlorella, which were further coated with a compact layer of ZIF-8 nanoparticles. The as-prepared microrobots could be flexibly actuated with high velocity under magnetic actuation. Besides, a series of antibacterial tests were conducted to verify that Zn2+ was efficiently released from the ZIF-8 shell for bacterial inhibition, which could also be significantly enhanced via controlled magnetic propulsion. Due to their facile fabrication and remarkable versatility, MOF-loaded microrobots hold great potential for the active treatment of bacterial infections.