Simultaneous polarographic chemometric determination of lead, copper, vanadium, cadmium and nickel

Chemometric approaches, such as classical least squares (CLS), principal component regression (PCR), partial least squares (PLS) and iterative target transformation factor analysis (ITTFA), were applied to the simultaneous determination of mixtures of lead, copper, vanadium, cadmium and nickel by differential pulse polarography (DPP). The conventional and first-derivative polarograms of the mixtures were used to perform the optimization of the calibration procedure by chemometric models. The proposed method was applied satisfactorily to the determination of a set of synthetic mixtures of metal in Britton–Robinson buffer (pH 2.87) and potassium thiocyanate and acceptable results were obtained. The results obtained by the application of the different chemometric approaches are discussed and compared. It was found that factor analysis methods generally give better results than CLS and no significant advantages were found with the application of derivative technique, except for ITTFA in this polarographic work.