Aggregation-Enhanced Photocatalysis Powers Next-Generation Phototherapeutics.

Photocatalytic therapy (PCT) has emerged as an expanded framework for light-driven biomedicine. Specifically, photodynamic therapy (PDT) can be regarded as a classical oxygen-sensitized subtype, while broader photocatalytic pathways, including photoredox transformations, intracellular polymerization, and photocatalytic gas generation, further extend its scope. However, organic photocatalytic systems often suffer from photobleaching, poor aqueous compatibility, and aggregation-caused quenching, which reduce excited-state utilization and catalytic efficiency in biological media. Aggregation-induced emission luminogens (AIEgens) offer a promising strategy by suppressing nonradiative decay. Moreover, aggregation engineering can regulate photocatalytic processes by modulating charge transfer and excited-state dynamics. This Mini-Review summarizes recent advances in AIE-based organic photocatalytic systems for biomedical applications. In this context, AIEgens and aggregation effects are emphasized not only for overcoming the deactivation of conventional organic systems in the aggregated state but also for providing versatile molecular design principles for the development of efficient and biologically adaptable organic photocatalytic therapeutics.