Microrobots for Antibiotic-Resistant Skin Colony Eradication.

Self-propelled nano- and micromachines have immense potential as autonomous seek-and-act devices in biomedical applications. In this study, we present microrobots constructed with inherently biocompatible materials and propulsion systems tailored to skin-related applications. Addressing the significant treatment challenge posed by methicillin-resistant (MRSA) skin infections, we demonstrate that photocatalytic titanium dioxide microrobots decorated with silver or platinum can effectively and rapidly eradicate MRSA biofilms grown on skin-mimicking membranes and porcine skin tissues. These microrobots are powered by hydrogen peroxide or ultraviolet light─agents considered toxic in high concentrations but commonly used in controlled amounts for skin disinfection and naturally encountered by the skin. By examining the effects of different metal coatings on the propulsion abilities of the microrobots, we show that these chemically propelled devices can eliminate biofilms without causing significant damage to the surrounding skin tissues, as confirmed by histological analysis. This work paves the way for the use of microrobots in skin-related biomedical applications, particularly in cases where traditional antibiotics are ineffective.