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 2.15 × 105 M−1 and 9.57 × 104 M−1 for Cu2+ and Hg2+ ions, respectively, and both metals formed complexes with 5 at a 1:1 metal to ligand ratio. The binding of 5 to Cu2+ shows a broad pH range (5–10) and a low detection limit (57 ppb) in water, thus indicating it an efficient and promising cation probe.