Square wave anodic stripping voltammetric determination of lead(II) using a glassy carbon electrode modified with a lead ionophore and multiwalled carbon nanotubes

We report on a glassy carbon electrode (GCE) modified with a lead ionophore and multiwalled carbon nanotubes. It can be applied to square wave anodic stripping voltammetric determination of Pb(II) ion after preconcentration of Pb(II) at -1.0 V (vs. SCE) for 300 s in pH 4.5 acetate buffer containing 400 mu g L-1 of Bi(III). The ionophore-MWCNTs film on the GCE possesses strong and highly selective affinity for Pb(II) as confirmed by quartz crystal microbalance experiments. Under the optimum conditions, a linear response was observed for Pb(II) ion in the range from 0.3 to 50 mu g L-1. The limit of detection (at S/N = 3) is 0.1 mu g L-1. The method was applied to the determination of Pb(II) in water samples with acceptable recovery.