Determination of Folpet, Procymidone, and Triazophos in Groundwater by HPLC Using Partial Least Squares and Principal Component Regression

Abstract Three multivariate calibration methods, partial least squares (PLS-1 and PLS-2) and principal component regression (PCR), full spectrum calibration methods, were applied to the simultaneous determination of the three pesticides folpet, procymidone and triazophos, in mixtures, by high performance liquid chromatography with photodiode array detection (HPLC-DAD). The effects of several preprocessing techniques are discussed in order to optimize the calibration matrices by the PLS and PCR methods. The use of mean-centering and smoothing function chromatograms allows better prediction of the samples. The average recoveries from the different mixtures assayed ranged between 79.6 % and 114.0 %. No advantages were found for the prior differentiation step.