NIR laser triggered carbon monoxide, type I photodynamic and photothermal synergistic treatment of bacterial infected wounds

Bacterial infections stand as one of among the most common challenges encountered during wound healing. Although antibiotics have been employed to treat bacterial infections, the overuse and abuse of antibiotics has emerged as a significant global public health and societal concern, posing a serious threat to human health. Hence, the present study introduces a photo-responsive multifunctional nanoplatform (TCO NPs) that integrates type I photodynamic therapy (PDT), photothermal therapy (PTT), and CO gas-based therapeutic modalities for the treatment of bacterial infected wounds. This multifaceted nanoplatform comprises a near-infrared (NIR) absorbing photosensitizer (TDNH) and a metal-free carbon monoxide (CO) donor (3-HF). Upon irradiation with 808 nm laser, TCO NPs generate type I reactive oxygen species (ROS) and induce hyperthermia, effectively eradicating bacterial pathogens. Additionally, the ROS produced by TDNH triggers the controlled release of CO gas, which not only enhances antibacterial efficacy but also modulates inflammatory responses to facilitate tissue regeneration. Notably, this nanoplatform demonstrates a remarkable bacterial elimination rate exceeding 99 % in an abscess model under 808 nm laser exposure, underscoring its potential as a reliable approach for CO-enhanced PTT and type I PDT in the treatment of bacterial infected wounds. • TCO NPs can generate O2 • - and exhibit photothermal antibacterial properties under 808 nm irradiation, effectively disrupting bacterial membrane structure and demonstrating broad-spectrum sterilization against Gram-positive and Gram-negative bacteria. • TCO NPs can effectively type I ROS (O2•−) under 808 nm irradiation, which subsequently activate 3-HF to release CO for synergistic antibacterial action. • TCO NPs integrate CO release, type I ROS generation, and hyperthermia to combat tissue infections. • TCO NPs effectively regulate proinflammatory cytokines to mitigate bacteria-induced inflammation, promote collagen deposition, and accelerate wound healing. Bacterial infections stand as one of among the most common challenges encountered during wound healing. Although antibiotics have been employed to treat bacterial infections, the overuse and abuse of antibiotics has emerged as a significant global public health and societal concern, posing a serious threat to human health. Hence, the present study introduces a photo-responsive multifunctional nanoplatform (TCO NPs) that integrates type I photodynamic therapy (PDT), photothermal therapy (PTT), and carbon monoxide (CO) gas-based therapeutic modalities for the treatment of bacterial infected wounds. This multifaceted nanoplatform comprises a near-infrared (NIR) absorbing photosensitizer (TDNH) and a metal-free CO donor (3-HF). Upon irradiation with 808 nm laser, TCO NPs generate type I reactive oxygen species (ROS) and induce hyperthermia, effectively eradicating bacterial pathogens. Additionally, the ROS produced by TDNH triggers the controlled release of CO gas, which not only enhances antibacterial efficacy but also modulates inflammatory responses to facilitate tissue regeneration. Notably, this nanoplatform demonstrates a remarkable bacterial elimination rate exceeding 99 % in a full-thickness skin defect infection model under 808 nm laser exposure, underscoring its potential as a reliable approach for CO-enhanced PTT and type I PDT in the treatment of bacterial infected wounds.