Peptide-mediated Aqueous Synthesis of NIR-II Emitting Ag2S 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 Ag2S quantum dots (QDs). The AgBP2 capped Ag2S 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-Ag2S 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-Ag2S 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.

Automated summary

In this study, a biomimetic silver binding peptide AgBP2 was used to develop a simple synthesis method for biocompatible Ag2S quantum dots (QDs). The AgBP2 capped Ag2S QDs showed excellent fluorescence emission in the NIR-II window and exhibited physical and photostability in water. Under 808 nm NIR laser irradiation, AgBP2-Ag2S QDs acted as a photothermal agent for NIR photothermal conversion and a photocatalyst for generating reactive oxygen species (ROS). The obtained AgBP2-Ag2S QDs achieved a highly effective disinfection efficacy of 99.06% against Escherichia coli within 25 min of NIR irradiation, attributed to the synergistic effects of photogenerated ROS and hyperthermia. This work demonstrates a promising strategy for efficient bacterial disinfection.