A selective fluorescent probe for the determination and imaging of fluoride in living cells

Fluoride anions are indispensable trace elements required for sustaining life. To investigate the homeostasis and action of fluoride in the body, a new highly sensitive and selective fluorescence detection method was designed for fluoride in aqueous solutions. A fluorescent probe for fluoride (FP-F) was synthesized for imaging F^- in living cells. The design strategy for the probe was based on the specific reaction between fluoride and silica to mediate deprotection of this probe to fluorescein. Upon treatment with F^-, FP-F, a closed and weakly fluorescent lactone, was transformed into an open and strongly fluorescent product. Under the optimum conditions, the detection limit for fluoride was 0.526 nM. FP-F could detect micromolar changes in F^-concentrations in living cells by confocal microscopy. (author)