<i>In situ</i> dressing based on a D–π–A structured aggregation-induced emission photosensitizer for healing infected wounds

Photodynamic antimicrobial therapy (aPDT) can effectively kill bacteria without promoting drug resistance. However, the phototoxicity of photosensitizers in aPDT against normal cells hinders their practical applications. In this work, we report the utilization of an aggregation-induced emission (AIE)-active photosensitizer, DTTPB, to develop antibacterial dressing for effective eradication of both Gram-positive and Gram-negative bacteria. The D-π-A structure of DTTPB facilitates efficient ROS generation in the aggregate state, addressing the limitations of a traditional photosensitizer. Notably, DTTPB demonstrates good biocompatibility towards normal cells, which minimizes its phototoxicity to normal tissues. To demonstrate its practical implications, DTTPB is combined with Carbomer 940 to create an injectable hydrogel dressing (DTTPB@gel). DTTPB@gel not only adheres to wounds but also maintains the antimicrobial properties of DTTPB, which together contributes to its enhanced wound-healing performance. Biocompatibility and toxicity assessments confirm the safety of this novel material, highlighting its potential as a practical and effective treatment for bacterial infections in wounds. The results underscore the importance of innovative antimicrobial strategies in fighting against antibiotic resistance, paving the way for safer and more effective therapeutic options.