ROS-Responsive Mitochondria-Targeting Blended Nanoparticles: Chemo- and Photodynamic Synergistic Therapy for Lung Cancer with On-Demand Drug Release upon Irradiation with a Single Light Source.

Mitochondria in cancer cells maintain a more negative membrane potential than normal cells. Mitochondria are the primary source of cellular reactive oxygen species (ROS), which are necessary for photodynamic therapy. Thus, the strategy of targeting mitochondria can maximize the photodynamic therapeutic efficiency for cancer. Here we report, for the first time, synthesis of a new mitochondria-targeting drug delivery system, ZnPc/CPT-TPPNPs. To synthesize this novel compound, polyethylene glycol was functionalized with thioketal linker-modified camptothecin (TL-CPT) and triphenylphosphonium to form the block copolymer, TL-CPT-PEG