Nanodot-doped peptide hydrogels for antibacterial phototherapy and wound healing

Abstract

Bacterial infection of wounds delays the healing process, increases the risk of chronic trauma associated with pain and complications, and offers a breeding ground for drug-resistant bacteria. A rapid and effective eradication of the bacterial species in the wound area is thus important. Herein, we designed a phototherapeutic antibacterial platform based on peptides and copper sulfide nanodots (CuS NDs) for multi-mechanistic eradication of bacteria colonized on the wound surface. The antimicrobial peptide weaves into a network in the form of a hydrogel, which supports CuS NDs to generate heat and produce reactive oxygen species (ROS) under the irradiation of near-infrared light (NIR). The heat and ROS generated in situ act as non-contact-based antibacterial factors and together with contact-based antimicrobial peptides cause irreversible membrane destruction, cell content damage, and thermal ablation of the bacteria. Lastly, nanodot-doped peptide hydrogels combined with collagen showed complete bacterial elimination and significantly accelerated wound healing in a splint-fixed mouse infection model.