Catalytic magnetic robots remove biofilm

Microrobots Biofilms can cause problems in medicine ranging from catheter clogs to tooth decay. Hwang et al. applied iron oxide nanoparticles (NPs) to the task of biofilm dissolution. When mixed with hydrogen peroxide, NPs form free radicals that are bactericidal and contribute to the degradation of the biofilm matrix. A magnetic field was used to induce motion of the NPs, enabling mechanical disruption of surface biofilms. To access small spaces, the authors molded various shapes from polymer-embedded NPs. A helical structure was able to travel through catheters, and NP aggregates were tested in the root canal of extracted human teeth. Sci. Robot. 4 , eaaw2388 (2019).