A new chemosensor for the Cu(II) ion has been realized by connecting via an amido bond an anthracenyl residue to the all cis 2,4.6-triamino-1,3,5-trihydroxycyclohexane ligand (TACI). This sensor is able to detect micromolar concentrations of Cu(II) ions in water at pH 7 without interference with many other divalent transition metal ions. (C) 2001 Elsevier Science Ltd. All rights reserved.