Sunlight-driven nanoheterojunctions for synergistic antimicrobial therapy and infected wound healing

• Sunlight-driven nanoheterojunctions enable synergistic antimicrobial therapy. • Antibiotic-free material eradicates bacteria via reactive oxygen species generation. • Nanoheterojunctions demonstrate exceptional efficacy under sunlight and indoor light. • Nanoheterojunctions accelerate infected wound healing to 96.7 % in 9 days in mice. • High cell viability and negligible organ toxicity confirm favorable biosafety. Bacterial infections at wound sites can significantly impede the healing process, often leading to chronic or non-healing wounds. In this study, we successfully synthesized NaGdF 4 :Yb,Er@ZIF-8/MnO 2 (UCZM) nanoheterojunctions, which demonstrate exceptional photodynamic and chemodynamic antimicrobial activities. Upon light exposure, UCZM generates reactive oxygen species, contributing to its potent antimicrobial effects. In the dark, UCZM exhibited antimicrobial efficacy of 74.1 % against Staphylococcus aureus ( S. aureus ) and 65.8 % against Escherichia coli ( E. coli ). Under simulated sunlight and 980 nm near-infrared light, as well as natural indoor and outdoor sunlight, antimicrobial activity reached 98.7 %, 97.4 %, 98.2 %, and 87.0 % against S. aureus , and 97.6 %, 94.1 %, 95.1 %, and 77.4 % against E. coli . In vitro cytotoxicity assays revealed that HEK-293 cell viability remained at 97.4 % after 24 h of exposure to 25 mg/L UCZM, decreasing to 79.9 % at 800 mg/L, indicating favorable biosafety. In vivo , UCZM significantly accelerated wound healing in infected mice. The UCZM + light-treated group exhibited a dramatic reduction in wound size, with only 3.3 % of the original wound area remaining after 9 days, compared to a larger wound area in the control group. These results highlight UCZM’s potential as an effective antimicrobial agent for clinical wound healing, particularly for infected wounds.