COMPARISON OF MULTICOMPONENT DETERMINATION OF IPRODIONE, PROCYMIDONE AND CHLOROTHALONIL BY PARTIAL LEAST-SQUARES MODELING USING SPECTROPHOTOMETRIC AND HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY DATA

A Partial Least Squares (PLS) calibration method was applied to the si multaneous determination of iprodione, procymidone and chlorothalonil in mixtures, by uv-vis absorption spectrophotometry and by high perfor mance liquid chromatography (HPLC). Signals and first-derivative (D-1) signals were used to optimize the calibration matrices by the PLS-1 m ethod. Quantitative results are presented for synthetic mixtures and f or extracts from soil and groundwater samples. Significant improvement s were achieved by using the PLS-1 method built with first-derivative chromatograms, in the determination of iprodione, procymidone and chlo rothalonil in environmental samples.