A rhodamine-based fluorescent probe for Hg2+ and its application for biological visualization

A new visible light excitable rhodamine-based Hg2+ probe has been designed and synthesized. The probe exhibits reversible colorimetric and fluorescent responses towards Hg2+. O-N-N-O recognition site in the probe plays a dominant role in forming a complex with 1:1 stoichiometry of Hg2+ to the probe. Furthermore, the probe has been successfully employed as a fluorescent probe for visualization of Hg2+ in living HeLa cells.