A Glance on target specific PDT active cyclometalated iridium complexes

Light is indispensable to every aspect of our life. It is also a very important component of photodynamic therapy to cure cancer. Photodynamic therapy is a modern and effective technique among all these prevailing anticancer therapies because of its uniqueness in selectivity. Organometallic complexes are seen to be better candidates for photodynamic therapy. Cyclometalated complexes have been developed for targeting cellular organelles with remarkable photoactivity. Different types of metal complexes can display PDT activity. Considering its photophysical characteristics, the iridium complex is the most effective alternative to use as a PDT agent. Iridium-based cyclometalated complexes have shown decent results as a PDT-active anti-cancer agent. Reactive oxygen species (ROS) and singlet oxygen with high singlet oxygen quantum yield are both extremely capable of being produced by complexes. High cytotoxicity has been exhibited by various Iridium-based cyclometalated complexes in the presence of light and negligible cytotoxicity in dark conditions. These complexes are considerably fluorescent with the capability of cellular imaging and have displayed very significant potency against HeLa, A549, MCF-7, and other various cell lines. Complexes can arrest the different paths of the cell cycle through different mechanisms and help to force cellular apoptosis. Hence, a galore of organelle-targeted cyclometalated iridium complexes has been showcased in this review article.