A Multielement Masking Method Using Magnesium Hydroxide Coprecipitation for the Selective Determination of Lead in Water Samples by Differential Pulse Anodic Stripping Voltammetry

Abstract

We present a new multielement masking method using magnesium hydroxide coprecipitation for the selective determination of Pb by differential pulse anodic stripping voltammetry (DPASV). The recovery of Pb in the masking method was over 95%, while interfering ions (Cd²⁺, Co²⁺, Cu²⁺, Fe³⁺, Mn²⁺, and Ni²⁺) could be removed at 100% from the analytical sample. A linear regression was obtained in the Pb concentration from 10 to 1000 µg kg^-1 in the existence of 100 µg kg^-1 of the interfering ions. When this method was applied to the determination of Pb in a natural water-standard reference material (NIST 1640), the determined value for Pb in this work (25.4 ± 4.1 µg kg^-1) almost agreed with the certified value (27.89 ± 0.14 µg kg^-1).