A Polyanionic Dendritic Fluorophore for Selective Detection of Hg2+ in Triton X-100 Aqueous Media

A series of water-soluble fluorescent dendritic compounds composed of phenylene-ethynylene repeating units and anionic carboxylate or cationic ammonium peripheral groups were synthesized. The first generation fluorescent dendrimer containing nine phenylene-ethynylene units and six carboxylate peripheral groups exhibited a highly selective fluorescence quenching by Hg2+ ions. The Stern-Volmer constant (K-sv) was 33,700 M-1 in aqueous media in the presence of Triton X-100 surfactant.