Emerging Designs of Aggregation-Induced Emission Agents for Enhanced Phototherapy Applications

Phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), that employs phototherapeutic agents to generate cytotoxic reactive oxygen species (ROS) or hyperthermia, is a promising approach for disease therapy. However, conventional organic phototherapeutic agents suffer poor photostability and aggregation-caused quenching (ACQ) in the aggregate state, restricting their therapeutic efficacy. Aggregation-induced emission (AIE) agents can solve these issues with strong emission in the aggregate state and reverse designation to generate heat. This review summarizes the recent advances in the development of AIE phototherapy agents for enhanced PDT and PTT performances in biomedical applications. First, design strategies of AIE agents that adjust the intersystem crossing process or intramolecular charge transfer to boost ROS generation or regulate ROS types are discussed. The AIE agents with ROS generation ability for biomedical applications including antitumor and antibacterial performances are then introduced. Next, designs and examples of AIE agents that enhance PTT performances through molecular motions are described. Finally, the current challenges and perspectives of AIE agents in the phototherapy field are discussed. [GRAPHICS] .