Molecular engineering to achieve AIE-active photosensitizers with NIR emission and rapid ROS generation efficiency

作者：Ding, Guanyu; Tong, Jialin; Gong, Jianye; Wang, Zhiming; Su, Zhongmin^*; Liu, Lu; Han, Xu; Wang, Jianguo^*; Zhang, Lingyu; Wang, Xinlong; Wen, Li-Li^*; Shan, Guo-Gang^*

来源：Journal of Materials Chemistry B, 2022, 10(27): 5272-5278.

DOI：10.1039/d1tb02738g

• AGGREGATION-INDUCED EMISSION
• PHOTODYNAMIC THERAPY
• ORGANIC NANOPARTICLES
• FLUORESCENCE
• PHTHALOCYANINES
• DESIGN
• AGENTS

Near-infrared (NIR) photosensitizers with rapid reactive oxygen species (ROS) production ability are in great demand owing to their promising performance toward boosting photodynamic therapy (PDT) and deep-tissue imaging, but molecular design guidelines for efficient photosensitizers are rarely elucidated. Herein, three AIEgens named DBP, TBP, and TBP-SO3 are designed and synthesized by precise donor-acceptor (D-A) molecular engineering to deeply understand the structure-property-application relationships. All the compounds exhibit AIE characteristics with strong long-wavelength emission in the aggregated state and are capable of efficiently producing ROS under white light irradiation. By controlling the ability of the D-A units, TBP-SO3 realizes NIR emission and more rapid ROS generation ability due to the promoted intersystem crossing processes compared with those of DBP and TBP. In addition, NIR-emitting TBP-SO3 is capable of specific endoplasmic reticulum targeting and excellent PDT treatment ability of cancer cells and bacteria. This successful example of molecular engineering paves a valuable way for developing advanced PSs with AIE properties, efficient ROS generation ability, and intense emission for fluorescence imaging PDT.