Construction of AIE Molecule-Embedded Long-Persistent Luminescence Coating for Self-Activated Photodynamic Antibacterial Performance

Photodynamic therapy (PDT) has emerged as a pivotal strategy for mitigating the risk of implant-associated infections (IAIs) due to its minimally invasive nature and the reduced emergence of multidrug-resistant (MDR) bacterial strains. However, the limited tissue penetration depth of visible light fundamentally constrains the therapeutic efficacy of PDT in deep-seated infections. Herein, we engineered a self-luminescent polydimethylsiloxane (PDMS) composite (PDMS-S) by integrating persistent luminescence material (Sr2MgSi2O7: Eu2+, Dy3+). Simultaneously, we encapsulated an aggregation-induced emission luminogen (AIEgen; TTVP) with exceptional photosensitizing efficiency within a hybrid polymeric network of phytic acid (PA) and carboxymethyl chitosan (CMCS). The resulting PA-CMCS-TTVP (PA-CT) aggregates are conveniently deposited onto PDMS-S surfaces. The intrinsic luminescence of PDMS-S enabled the PA-CT coating to generate sustained reactive oxygen species (ROS), resulting in long-term effective PDT. This work significantly expands the biomedical applications of PDT and provides a transformative strategy for deep-tissue infections.