7-Aminocoumarinyldisulfide as a ratiometric fluorescent probe for biothiols in water

We report an aminocoumarine-based fluorescent probe (1) possessing a disulfide group to detect biothiols in HEPES buffer. Prominent ratiometric fluorescence changes of the probe are induced by the disulfide bond cleavage of 1 upon the addition of biothiols. The ratiometric probe (1) exhibits both high sensitivity and selectivity toward amino acids containing a thiol group over other various amino acids in water.