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 O-1(2) under the trigger of acidity. Notably, the O-1(2) 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 O-1(2). 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 O-1(2) and achieve more accurate real-time and in situ monitoring of O-1(2) production during therapy.