Photothermal-Driven α-Amylase-Modified Polydopamine Pot-Like Nanomotors for Enhancing Penetration and Elimination of Drug-Resistant Biofilms

Biological enzyme-functionalized antibacterial nanoparticles, which can degrade biofilm and kill bacteria under mild reaction conditions, have attracted much attention for the elimination of deep-seated bacterial infections. However, the poor diffusion and penetration capabilities of recently developed biological enzyme-functionalized antibacterial nanoparticles in biofilm severely impair the eradication efficacy of deep-seated bacteria. Herein, a photothermal-driven nanomotor (denoted as APPNM) is developed for enhancing the elimination of drug-resistant biofilms and the eradication of deep-seated bacteria. The nanomotor contained a pot-like polydopamine (PDA) nanostructure and its outer surface is chemically immobilized with a layer of α-amylases. Under exposure to 808 nm near-infrared (NIR) laser irradiation, the self-propelled nanomotors, integrating the α-amylases to destroy the compact structure of biofilms, can penetrate deeply into biofilms and effectively eliminate them. Subsequently, they can accumulate on the surface of bacteria using the inherent bio-adhesion property of PDA, thereby completely eradicating deep-seated bacteria by photothermal effect. These synergistic effects enable them to exhibit superior antibiofilm effects and produce remarkable therapeutic efficacy with accelerated wound healing in vivo. With excellent biocompatibility, the as-developed nanomotors have great potential to be applied for treating biofilm-related infections.