Side Chain Engineering of Amphiphilic Conjugated Polymer Nanoparticles for Biofilm Ablation

Biofilm recalcitrance, which enables bacteria to survive deep within the body under antimicrobial treatment, leading to persistent infections by reducing the penetration of antimicrobials, remains a major challenge in the antibacterial field. Conjugated polymer-based nanoparticles with near-infrared (NIR) photo responsiveness have emerged as a promising class of photothermal agents for biofilm ablation. However, the development of CPNs has been limited due to dissociation of the nanoparticles synthesized through nanoprecipitation. In this study, surface-functionalized amphiphilic conjugated polymer-based nanoparticles with photothermal conversion capacity for pH-responsive targeting of bacteria are developed. The pH-sensitive properties of the nanoparticles promote their adhesion to negatively charged bacterial surfaces, resulting in accumulation in biofilms. This accumulation enhances the ablation efficiency of biofilms under the synergistic photothermal effect. The method of constructing functional amphiphilic conjugated polymer-based nanoparticles is simple to operate and can be used universally, providing a potential design option for biocompatible light-responsive nanoparticles for in vivo applications.