Fast and Simultaneous Determination of Pb2+ and Cu2+ in Water Samples using a Solid Paraffin-Based Carbon Paste Electrode Chemically Modified with 2-Aminothiazole-Silica-Gel

A solid paraffin-based carbon paste electrode modified with 2-aminothiazole functionalized silica-gel was used for simultaneous quantification of Pb2+ and Cu2+ in water samples by anodic stripping voltammetry. The present method uses short preconcentration time (180 s), which allowed reliable and simultaneous quantification of Pb2+ and Cu2+ in a very fast way. Detection limits of 7.3 and 90 nmol L-1 were obtained for Pb2+ and Cu2+, respectively. These values are below their maximum concentrations allowed in drinking water by Brazilian legislation, indicating that the proposed method is useful to monitoring Pb2+ and Cu2+ in water samples. Recovery studies were performed in four spiked water samples and the results shown recovery percentages close to 100% for all analyzed samples, demonstrating the good accuracy of the proposed method.