Cyclic Amplification of the Afterglow Luminescent Nanoreporter Enables the Prediction of Anti‐cancer Efficiency

We developed a cyclic amplification method for an organic afterglow nanoreporter for the real-time visualization of self-generated reactive oxygen species (ROS). We promoted semiconducting polymer nanoparticles (PFODBT) as a candidate for emitting near-infrared afterglow luminescence. Introduction of a chemiluminescent substrate (CPPO) into PFODBT (PFODBT@CPPO) resulted in a significant enhancement of afterglow intensity through the dual cyclic amplification pathway involving singlet oxygen (1 O2 ). 1 O2 produced by PFODBT@CPPO induced cancer cell necrosis and promoted the release of damage-related molecular patterns, thereby evoking immunogenic cell death (ICD)-associated immune responses through ROS-based oxidative stress. The afterglow luminescent signals of the nanoreporter were well correlated with light-driven 1 O2 generation and anti-cancer efficiency. This imaging strategy provides a non-invasive tool for predicting the therapeutic outcome that occurs during ROS-mediated cancer therapy.