Sensitive square wave anodic stripping voltammetric determination of Cd2+ and Pb2+ ions at Bi/Nafion/overoxidized 2-mercaptoethanesulfonate-tethered polypyrrole/glassy carbon electrode

Square wave anodic stripping voltammetry was applied to detect Pb2+ and Cd2+ ions at a glassy carbon electrode modified with overoxidized 2-mercaptoethanesulfonate (MES)-tethered polypyrrole, Nafion and Bi. The PPy-MES interaction was examined by quartz crystal microbalance. Under optimum conditions (5-min preconcentration at -1.2V vs. SCE in pH 4.0 acetate buffer containing 300 mu g L-1 Bi3+), the linear calibration curves ranged from 0.05 to 35 mu g L-1 for Pb2+ and 0.1 to 25 mu g L-1 for Cd2+, respectively, and the limits of detection (S/N = 3, S is the signal and N is the noise level) were 0.03 mu g L-1 for Pb2+ and 0.04 mu gL(-1) for Cd2+. This method was successfully applied for Pb2+ and Cd2+ analysis in real water samples. (C) 2013 Elsevier B.V. All rights reserved.