BINARY MIXTURES BY A PARTIAL LEAST SQUARE METHOD COMBINED WITH MICELLAR-ENHANCED PHOTOCHEMICALLY-INDUCED FLUORESCENCE APPLICATION TO TAP WATER ANALYSIS

A combination of the partial least square method in its first variable (PLS-1) with micellar-enhanced photo-chemically-induced fluorescence (MEPIF) was developed for the simultaneous determination of synthetic binary mixtures of four sulfonylurea herbicides in aqueous micellar solutions, and applied to tap water analysis. Because of their similar features, the MEPIF emission spectra of these herbicides were found to severely overlap in the whole wavelength region. After optimization of the calibration matrix, the PLS-1-MEPIF method was applied to the resolu-tion of chlorsulfuron/metsulfuron methyl and sulfometuron methyl/3-rimsulfuron binary mixtures. The analytical re-sults obtained by the PLS-1-MEPIF method were presented and compared to those of the first-derivative PIF one. An application of the PLS-1-MEPIF method to the quantitative analysis of Paris tap water samples spiked with the herbi-cide binary mixtures led to recovery values ranging between 63 and 118 %, depending on the mixture. Key words: partial least square; micellar-enhanced photochemically-induced fluorescence; sulfonylurea herbicides; tap water analysi