A Hg2+ fluorescent chemosensor without interference from anions and Hg2+-imaging in living cells

A fluorescent chemosensor, B2, for Hg2+ containing a BODIPY fluorophore and carboxyl-thiol metal-bonding moieties was described. B2 exhibits selective fluorescence enhancement (123-fold) toward Hg2+ over other metal ions. Especially, the fluorescence enhancement was unaffected by anions existing in environment and organism. B2 shows high sensitivity to Hg2+ in a concentration of ppb range with detection limit of 77 nM. B2-ester, the membrane-permeable ethyl ester, is able to be hydrolyzed to B2in vivo, and successfully applied to image intracellular Hg2+ in living cells.