Synthesis and in vitro biological evaluation of novel water‐soluble porphyrin complexes for cancer photodynamic therapy

In this study, we report the synthesis and biological evaluation of four novel cationic porphyrins (named as P1, P2, ZnP2, and CuP2) with potential as a photodynamic therapeutic agent. MTT experiments proved that P1, P2, and ZnP2 have high light toxicity and low dark toxicity for A549, H‐1975, and HepG2 cell lines. In addition, due to the specific targeting of porphyrin, there was only a weak toxicity to Hs 578Bst normal breast cancer cells. The study further confirmed the intracellular generation of reactive oxygen species (ROS) under light irradiation and ZnP2 could be effectively internalized by cells and also indicated that the photodynamic therapy effect achieved by ZnP2 and light irradiation can cause significant cell apoptosis. High relative singlet oxygen quantum yield and excellent phototoxicity ensure the optimal photosensitizer ZnP2 becomes potential candidates for photodynamic therapy drugs. Our results disclosed that the cationic porphyrin complexes used photodynamic therapy for the development of new and useful metal anticancer photosensitizer provide a strong platform. Four complexes (P1, P2, ZnP2, CuP2) have been appeared and evaluated for their photodynamic activity and potential antitumor activities in vitro.