Oxygen-Propelled CoFe2O4@C Nanorobots: Dual-Enzyme-Driven bacterial biofilm disruption and water decontamination

Bubble-propelled micro/nanorobots face challenges in wastewater remediation, including reliance on noble metals, restricted catalytic versatility, and limited efficacy against bacterial biofilms. This paper presents the construction of a self-propelled CoFe 2 O 4 @C nanorobot exhibiting dual enzyme-like capabilities (peroxidase, POD; catalase, CAT) by a facile carbonization method. Hydroxyl radicals (·OH) are generated through the Fenton reaction in the presence of hydrogen peroxide (H 2 O 2 ), achieving up to ∼ 100 % degradation of organic dyes (e.g., methylene blue). Additionally, oxygen (O 2 ) gas is produced via CAT-mimetic enzyme activity to propel the movement of nanorobots. Notably, the nanorobot’s cascade-generated reactive oxygen species (ROS) demonstrate dual antibacterial capabilities: (1) eradicating 99 % of planktonic E. coli in water and (2) disrupting resilient bacterial biofilms—representing a significant advancement over conventional antibacterial technologies. Furthermore, its magnetic properties enable rapid retrieval, maintaining 95 % catalytic efficiency after five cycles. In summary, the synthesized nanorobot is cost-effective and exhibits simultaneous chemical decontamination and biofilm elimination in wastewater.