Purine-based Ir(iii) complexes for sensing viscosity of endo-plasmic reticulum with fluorescence lifetime imaging microscopy.

Novel purine-based iridium complexes were designed for selective determination of ER viscosity. The Ir-PH possessed excellent ER targeting ability and could distinguish the viscosity changes under ER stress by fluorescence lifetime image microscopy (FLIM), which may accelerate the development of relative quantitative detection of microenvironment changes at the subcellular level.