A water-soluble sulfonate-BODIPY based fluorescent probe for selective detection of HOCl/OCl⁻ in aqueous media.

A new, water-soluble BODIPY dye 1, bearing sulfonate groups at the 2- and 6-positions was found to be a sensitive and selective fluorescent probe for the detection of HOCl/OCl(-) in aqueous buffer solution. The probe, which displays extremely weak fluorescence owing to efficient singlet excited state quenching by photoinduced electron transfer (PeT) from an electron-rich catechol group at a meso-position, responds to HOCl/OCl(-) through a dramatic enhancement of its fluorescence intensity.