Heterojunction-enhanced photodynamic uterine scaffold mediated by upconversion for treating infectious injuries

Bacterial infection following endometrial injury would delay tissue regeneration and further progress to endometritis and other reproductive disorders. Photodynamic therapy (PDT) is a promising bacterial strategy in the postantibiotic era. However, its therapeutic efficacy is often limited by the rapid recombination of photogenerated charge carriers and the limited penetration depth of visible excitation light. In this study, we report a previously unexplored up-conversion-mediated, Type I dominant photodynamic antibacterial uterine scaffold specifically designed for infection-associated endometrial injury. The core innovation lies in the construction of a Schottky Ag 0 -Ag 2 S heterojunction on the surface of NaYF 4 :Yb,Tm nanoparticles using ZIF-8 as a sacrificial precursor, which enabled highly efficient charge separation and oxygen-independent hydroxyl radical generation, effectively overcoming the inherent oxygen dependence and compromised performance of conventional Type II PDT under hypoxic uterine conditions. The upcon-version core further enables deep-tissue-penetrable NIR activation, addressing the poor penetration of visible light. Moreover, beyond instantaneous PDT, the dynamic release of Ag + ions provides synergistic bactericidal activity, enabling spatiotemporally coordinated biofilm disruption. Importantly, these nanostructures were incorporated into patient-customizable, biodegradable PLLA scaffolds fabricated by selective laser sintering, achieving simultaneous antibacterial therapy and endometrial regeneration in a single platform. Collectively, the integration of an oxygen-independent PDT mechanism, MOF-templated heterojunction engineering, and 3D printed personalized uterine implants constitutes a comprehensive therapeutic strategy not previously reported for treating infection and endometrial injury. The alternative text for this image may have been generated using AI.