A highly Cu(II) ion-selective PVC membrane sensor based on 4-Amino-6-methyl-1,2,4-triazin-5-one-3-thione (AMTOT) as an excellent sensing material was developed. The electrode exhibits a linear dynamic range between 1.0×10-1 and 1.0×10-6 mol L-1, with a near Nernstian slope of 29.3 ± 0.6 mV per decade and a detection limit of 6.2×10-7 mol L-1. The sensor response is independent of the pH of the solution in the pH range of 2.5 - 7.0. The sensor possesses the advantages of short conditioning time, fast response time (<20 s), and especially, very good selectivity towards transition and heavy metal, and some mono, di and trivalent cations. The electrode can be used for at least 9 weeks without any considerable divergence in the potentials. The proposed electrode was successfully applied to the determination of copper in wastewater of copper electroplating samples and as an indicator electrode in potentiometric titration of Ca(II) ions with EDTA.
potentiometry; copper sensor; PVC membrane; 4-amino-6-methyl-1,2,4-triazin-5-one-3-thione
