Live cell-specific fluorescent probe for the detection of labile Fe(II) and the evaluation of esterase activity in live animals

Abstract Fe(II) plays critical roles in a variety of biologically important processes in living systems, and monitoring labile Fe(II) level could contribute to the in-depth study of its biological roles. Herein, we present a live cell-specific probe (RAcy) for the detection of labile Fe(II) ion in living cells and animals. The probe RAcy was equipped with an acetate group as a switch, which could selectively activate the capacity of the probe to detect Fe(II) in live cells instead of dead cells. The probe RAcy could provide a highly sensitive and selective response to Fe(II) ion in the presence of esterase in live cells. Imaging experiments showed that RAcy could be used as live cell-specific probe for the imaging of labile Fe(II) ion in live cells and animals, and also could be applied to the evaluation of esterase activity in live animals.