Ag-Coupled Polymeric Nanohybrids with Synergistic Photodynamic and Photothermal Activities for Advanced Antibacterial Therapy

Graphical A nonchemotherapic antibacterial agent was synthesized through one-step reprecipitation-encapsulation of photosensitizers, photothemal agents and poly-L-lysine (PLL), followed by the in-situ reduction of Ag on the surface of nanoparticle. The fabricated nanohybrids achieved a robust PDT/PTT/Ag antibacterial capability without apparent systemic toxicity. Considering the implications of inherent resistance of pathogenic bacteria, it is important to design a new generation of nonchemotherapic nanoagents for effective antibacterial therapy. Herein, we illustrate a one-step reprecipitation-encapsulation strategy to incorporate hydrophobic photosensitizers (ZnPc) and photothemal agents (dopamine hydrochloride) with a cationic poly-L-lysine (PLL) layer. Upon light irradiation, the polymeric nanohybrid exhibits high photo-to-thermal conversion efficiency (30.3%) and effective 1 O 2 generation capability. To further enhance the antibacterial efficiency, Ag nanoparticle, a typical broad-spectrum antibacterial agent, was decorated on the surface of PLL layer by in-situ reduction. The as-synthesized nanohybrids, referred to as ZnPc/DA@Ag, achieved a robust photodynamic/photothermal/Ag antibacterial capability without apparent systemic toxicity, thus holding great potential for broad-spectrum eradication of pathogenic bacteria.