A water-soluble ribosyl-based fluorescent sensor for Hg2+ and Cu2+ ions

A water-soluble ribosyl-based fluorescent sensor 5 was prepared. The sensor contains an anthracene as the fluorophore and a set of complex groups as recognition sites, which bears two triazole ring spacers linked to two ribosyl carboxylic acids groups. The association constants of 5 in water are 2.15x10(5)M(-1) and 9.57x10(4)M(-1) for Cu(2+) and Hg(2+) ions, respectively, and both metals formed complexes with 5 at a 1:1 metal to ligand ratio. The binding of 5 to Cu(2+) shows a broad pH range (5-10) and a low detection limit (57ppb) in water, thus indicating it an efficient and promising cation probe.