Magnetically Driven Hydrogel Microrobots for Targeted Antibiotic Delivery

Precise targeted delivery of antibiotics to infected sites is crucial for enhancing therapeutic efficacy and minimizing side effects. In this work, we present magnetic hydrogel-based microrobots for active antibiotic delivery to achieve targeted bacterial elimination. These microrobots comprise a poly(acrylic acid-co-acrylamide) hydrogel microspheres encapsulating Fe₃O₄ nanoparticle chains. The hydrogel scaffold offers abundant spaces and binding sites for high-capacity loading of vancomycin via electrostatic interactions. The embedded Fe₃O₄ nanochains enable magnetic propulsion. Under a rotating magnetic field (H_r(t)), the microrobots can actively deliver vancomycin to infected sites via their swarming motions, and then eliminate the bacteria (e.g., Staphylococcus aureus) utilizing their sustainable vancomycin release on site. These hydrogel-based microrobots hold great promise as a motile antibacterial platform to treat infectious diseases.