Peptide-mediated Aqueous Synthesis of NIR-II Emitting Ag S Quantum Dots for Rapid Photocatalytic Bacteria Disinfection

Pathogenic microorganisms in the environment are a great threat to global human health. The development of disinfection method with rapid and effective antibacterial properties is urgently needed. In this study, a biomimetic silver binding peptide AgBP2 was introduced to develop a facile synthesis of biocompatible Ag S quantum dots (QDs). The AgBP2 capped Ag S QDs exhibited excellent fluorescent emission in the second near-infrared (NIR-II) window, with physical stability and photostability in the aqueous phase. Under 808 nm NIR laser irradiation, AgBP2-Ag S QDs can serve not only as a photothermal agent to realize NIR photothermal conversion but also as a photocatalyst to generate reactive oxygen species (ROS). The obtained AgBP2-Ag S QDs achieved a highly effective disinfection efficacy of 99.06 % against Escherichia coli within 25 min of NIR irradiation, which was ascribed to the synergistic effects of photogenerated ROS during photocatalysis and hyperthermia. Our work demonstrated a promising strategy for efficient bacterial disinfection.