Interference Effects of Cu(II) and Pb(II) on the Stripping Voltammetric Detection of Cd(II): Improvement in the Detection Precision and Interference Correction

In this study, a novel analytical method for the quantitative determination of Cd(II) under the interference of Pb(II) and Cu(II) via a combination of square-wave anodic stripping voltammetry (SWASV) and chemometric methods is proposed. In addition, this study focuses on the analysis of interference in the electroanalysis of Pb(II), Cd(II) and Cu(II) with an in situ bismuth film-modified glassy carbon electrode (Bi/GCE). In the presence of these mutual interferences, the chemometric methods considerably improved the resolution of the voltammetric technique. The chemometric methods, namely, a back-propagation artificial neural network (BP-ANN), a particle swarm optimization-support vector machine (PSO-SVM) and a ternary linear regression equation (TLRE), were used to determine the Cd(II) concentration under the interference of Cu(II) and Pb(II). The prediction performances of the different chemometric methods were verified in terms of their root mean square errors (RMSEs), average relative errors (AREs), mean absolute errors (MAEs), and correlation coefficients (R2). The results indicate that the BP-ANN and PSO-SVM had higher prediction accuracies than the monadic linear regression equation (MLRE) and TLRE. Finally, the proposed method was used to determine the Cd(II) concentration in soil samples, with satisfactory results.