Photocatalytic Quantum Dot‐Armed Bacteriophage for Combating Drug‐Resistant Bacterial Infection

Abstract Multidrug‐resistant (MDR) bacterial infection is one of the greatest challenges to public health, a crisis demanding the next generation of highly effective antibacterial agents to specifically target MDR bacteria. Herein, a novel photocatalytic quantum dot (QD)‐armed bacteriophage (QD@Phage) is reported for combating green fluorescent protein‐expressing Pseudomonas aeruginosa (GFP‐ P. aeruginosa ) infection. The proposed QD@Phage nanosystem not only specifically binds to the host GFP‐ P. aeruginosa while preserving the infectivity of the phage itself, but also shows a superior capacity for synergistic bacterial killing by phage and by the photocatalytic localized reactive oxygen species (ROS) generated from anchored QD components. Notably, this highly targeted QD@Phage nanosystem achieves robust in vitro antibacterial elimination for both planktonic (over 99.9%) and biofilm (over 99%) modes of growth. In a mouse wound infection model, this system also shows remarkable activity in eliminating the wound infection and promoting its recovery. These results demonstrate that the novel QD@Phage nanosystem can diversify the existing pool of antibacterial agents and inspire the development of promising therapeutic strategies against MDR bacterial infection.