INDIRECT VOLTAMMETRIC DETERMINATION OF CARBARYL AND CARBOFURAN USING PARTIAL LEAST-SQUARES CALIBRATION

A differential pulse voltammetric method is proposed for the determina tion of the carbamate pesticides carbaryl and carbofuran, based on the anodic peaks observed following their alkaline hydrolysis (formation of phenol derivatives). Linear relationships between the oxidation pea ks and concentration were obtained in the ranges 5 x 10(-7) to 10(-4) M for carbaryl and 5 x 10(-7) to 5 x 10(-5) M for carbofuran, the rela tive standard deviations being 1.62 and 1.86%, respectively. The metho d was applied to the determination of these compounds in formulations. Different chemometric methods (PLS-1, PLS-2 and CLS) were examined fo r the resolution of the overlapped peaks of both compounds and their d etermination in mixtures. The best results were obtained with the PLS- 1 method, which was applied to determine both compounds in river water samples.