MXene@Fe₃O₄/PDA nanosheets with photothermal-magnetically coupled antibacterial properties

Pathogenic infections pose a major threat to global public health, and what's worse is that the bacteria in infected places often exist in the form of biofilms, making it impossible for antibiotics and other contact bactericidal substances to penetrate their interior. Therefore, looking for an effective method with synergistic antibacterial and biofilm removal properties is a key challenge. A kind of magnetic MXene@Fe₃O₄/PDA nanosheets with antibacterial properties of photothermal magnetic coupling are reported in this paper. Fe₃O₄ was grown in situ on MXene nanosheets and then coated with a layer of polydopamine (PDA). MXene@Fe₃O₄/PDA nanosheet (120 μg/mL) showed an over 95% inhibition rate against E. coli and S. aureus under 808 nm laser irradiation. In addition, peroxidase-like activity can produce reactive oxygen species. The photothermal antibacterial properties were further enhanced under the action of rotating magnetic field. The antibacterial activity was increased to close to 99.99%, and the removal effect of biofilm was also very good. The photothermal and magnetic coupled antibacterial effects can reduce the amount of MXene@Fe₃O₄/PDA, thus it is expected to reduce the damage caused by overheating normal tissues and is safer than pure photothermal therapy.