An anthracene-substituted benzoylthiourea for the selective determination of Hg(II) in micellar media

N-9-Anthrylmethyl-N-methyl-N'-benzoylthiourea (AnthBT) forms fluorescent complexes with several heavy metal ions. Strong increases in fluorescence intensity are observed upon complexation with the highly thiophilic Ag(I), Cu(I) and Hg(II) ions, while other ions do not alter fluorescence significantly. In the presence of the nonionic surfactant Triton X-100, only Hg(II) causes a higher fluorescence emission which is further enhanced by the surfactant. The increase in fluorescence intensity is proportional to the Hg(II) concentration and permits highly selective mercury determinations in the lower mu g/1-range. Ubiquitous metal ions, such as Fe(III), Al(III), alkaline and earth alkaline metal ions, can be tolerated up to concentrations of 10 g/l and more; Co(II), Ni(II), Cu(II), Zn(II), and Pb(II), up to a 20000-fold excess. (C) 1999 Elsevier Science B.V. All rights reserved.