Three water-soluble fluorophores are synthesized from 1,3,5-tris-(4′-iodophenyl)benzene. The compound with salicylate groups exhibits a selective fluorescent quenching by Cu2+via a static quenching mechanism. The addition of Triton X-100 improves the quantum efficiency of the fluorophore as well as the detection limit for Cu2+ from 6.49 to 0.19 ppb.