Light-free Generation of Singlet Oxygen through Manganese-Thiophene Nanosystems for pH-Responsive Chemiluminescence Imaging and Tumor Therapy

In chemodynamic therapy (CDT), novel chemodynamic reactions are urgently needed to promote the generating efficiency of reactive oxygen species (ROS), and meanwhile the real-time monitoring of ROS is really critical to minimize the toxic side effect of CDT. Herein, we develop a pH-responsive chemiluminescent and chemodynamic system (ultrathin Mn-oxides [MnOx] nanosheet - semiconducting polymer nanoparticles [SPNs]). We, for the first time, discover the capability of ultrathin MnOx nanosheets to generate 1O2 under the trigger of acidity. Notably, the 1O2 produced by MnOx can substitute light and specifically excite thiophene-based SPNs to emit photons for near-infrared chemiluminescent imaging, which greatly amplifies the generation of 1O2. Because of the intrinsic acidity within tumor, MnOx-SPNs realize the activatable chemodynamic therapy for solid tumor. Furthermore, the ratiometric chemiluminescent/fluorescent imaging is able to calibrate the output of 1O2 and achieve more accurate real-time and in situ monitoring of 1O2 production during therapy.