Selective Voltammetric Determination of Lead(II) on Partially Quaternized Poly(4-vinylpyridine)/Mercury Film Electrodes

A partially quaternized poly(4-vinylpyridine) mercury film electrode (QPVP/MFE) was developed for the determination of traces of Pb(II) in real samples by square-wave anodic stripping voltammetry. In this method, Pb(II) is converted into an anionic chloride complex and preconcentrated into the QPVP/MFE by applying a potential of −1.2 V (vs. Ag/AgCl). Good solubility of lead in mercury subsequently helps to increase the preconcentration effect. Various factors influencing the determination of Pb(II) were thoroughly investigated in this study. The main advantages of this method are a wide pH working range, good resistance to interference, easy detection without deoxygenating, and excellent electrode renewal. The analytical utility of the QPVP/MFE in the determination of Pb(II) is demonstrated by application to various water samples.