Nitric‐Oxide‐Enhanced Positively Charged Semiconductor Conjugated Polymer Composite Nanomaterials for Antibiofilm In Vivo

Abstract Bacterial biofilms often lead to persistent infections because they provide a protective barrier and reproductive microenvironment for bacteria. Biofilms reduce the therapeutic effects of antibiotics and can easily lead to the emergence of multidrug‐resistant bacteria. Therefore, development of new materials for antibiofilm with synergistic effects is crucial. In this study, positively charged near‐infrared‐responsive nanoparticles (TDPPB) are synthesized to control the release and delivery of nitric oxide (NO) gas. A combination of NO and photothermal therapy (PTT) is used to enhance the antibiofilm performance of TDPPB. The positive charge of TDPPB induces the nanoparticles to adhere to the surface of the bacteria. Through 808 nm laser irradiation, the local high temperature triggers the efficient release of NO from the NO donor (BNN 6) in TDPPB. TDPPB integrates the release of NO, and PTT presents good antibiofilm activity against MRSA and Escherichia coli ( E. coli ) biofilms. TDPPB demonstrates excellent biosafety both in vivo and in vitro, shows good antibiofilm properties in biofilm‐infected mice, and promotes the healing of surface‐infected sites in vivo. Because of these advantages, TDPPB can be used as a potential therapeutic agent against biofilm infections in the biomedical field.