A long-lifetime iridium(III) complex for lysosome tracking with high specificity and a large Stokes shift

Investigating the role of lysosome dysfunction in cancer requires the development of efficient probes for lysosomes. We report herein a cyclometalated iridium(III) complex (Ir-Ly) as a luminescent probe for visualizing lysosomes in cancer cells. The morpholine and hydroxy moieties within Ir-Ly provide suitable hydrophilicity and responsiveness to pH. Importantly, Ir-Ly exhibits a large Stokes shift, long lifetime and high photostability, which are important advantages for lysosome tracking in living cells.