| 초록 |
Photodynamic therapy (PDT) is one of the attractive alternatives to conventional cancer treatment using photosensitizers (PSs). A photosensitizer exhibited negligible dark cytotoxicity, but irradiation of a PS in the presence of molecular oxygen (O2) promotes the formation of reactive oxygen species (ROS). In general, excitation of fluorescent PSs possesses rather relatively short lifetimes and rapidly returns to the ground state from the lowest singlet excited state S1. On the contrary, the incorporation of heavy atoms into their core structures can have lower-lying triplet excited states Tn which are populated from S1 state through a spin-forbidden intersystem crossing (ISC) process. However, using heavy atoms in PSs often results of the issues such as dark toxicity, high-priced, low solubility, and other unwanted side issues. Therefore, the strategy to design and synthesize diverse triplet PSs without heavy atoms should be reported to match the desired clinical applications. |
