Determination of naphthalenesulfonates in water by on-line ion-pair solid-phase extraction and ion-pair liquid chromatography with fast-scanning fluorescence detection

A fast analytical method for quantifying a mixture of 12 naphthalenesulfona tes and naphthalenedisulfonates has been developed. This method consists of on-line ion-pair solid-phase extraction with PLRP-s sorbent and ion-pair l iquid-chromatography using fast-scanning fluorescence spectrometer as a det ection system and multivariate calibration. As complete separation is unnec essary, the compounds were analysed in isocratic conditions and the chromat ographic analysis took only 25 min. Three-way partial least-squares (PLS) w as used to carry out multivariate calibration for spiked tap water. in thes e conditions, quantification limits were between 0.01 and 3 mu g l(-1). Rep eatability was also evaluated and relative standard deviations (n = 3) were between 0.5 and 4, depending on the compound. Finally, spiked tap and Ebro river waters were analysed to evaluate prediction capability of the method . (C) 2000 Elsevier Science B.V. All rights reserved.