Low-Irradiance Antimicrobial Blue Light-Bathing Therapy for Wound Infection Control.

The prevalence of antibiotic resistance and tolerance in wound infection management poses a serious and growing health threat, necessitating the exploration of alternative approaches. Antimicrobial blue light therapy offers an appealing, non-pharmacological solution. However, its practical application has been hindered by the requirement for high irradiance levels (50-200 mW/cm), which particularly raises safety concerns. Here, a light-bathing strategy is introduced that employs prolonged, continuous exposure to blue light at an irradiance range lower by more than an order of magnitude (5 mW/cm). This method consistently applies bacteriostatic pressure, keeping wound bioburden low, all while minimizing photothermal risks. Leveraging tailor-made, wearable light-emitting patches, preclinical trials on rat models of wound infection are conducted, demonstrating its safety and efficacy for suppressing infections induced by methicillin-resistant Staphylococcus aureus (S. aureus) and multidrug-resistant Pseudomonas aeruginosa (P. aeruginosa). The results pave a new way for the application of blue light therapy in wound care.