A Cyclometalated Iridium(III) Complex Serves as a Phosphorescent Probe for Specific Mitochondrial Imaging in Living Cells

Abstract

AbstractA new cyclometalated iridium(III) complex [Ir(2‐pq)2(HPIP)]Cl (Ir1, 2‐pq=3‐phenylisoquinoline, HPIP=2‐(2‐hydroxyphenyl)imidazo[4,5‐f]1,10‐phenanthroline) was synthesized and applied to image mitochondria in living cells. Ir1 displayed excellent ability to selectively accumulate in mitochondria of live cells with no requirement of replacement of the culture medium. Due to Ir1 exhibiting better photostability than the commercially available mitochondrial trackers, this complex could be applicable for the imaging and tracking of the mitochondrial morphological changes over long periods of time. In addition, in vitro cytotoxicity investigation revealed that Ir1 showed negligible cytotoxicity at the concentrations employed. Based on these, Ir1 is suitable for organelle‐selective imaging in living cells.