Continuous solid-phase extraction and dansylation of low-molecular-mass amines coupled on-line with liquid chromatography and peroxyoxalate chemiluminescence-based detection

An on-line liquid chromatographic system involving solid-phase extraction, dansylation and peroxyoxalate chemiluminescence-based detection was used to determine low-molecular-mass amines in environmental water samples. Sample volumes of 50 ml were enriched in the amines by passage through an IRC-50 cation-exchange column, elution and on-line derivatization with 0.16 M bora te buffer (pH 11) and dansyl chloride, respectively, to a C-18 analytical c olumn, and determined by using an integrated derivatization-chemiluminescen ce detection unit based on the bis(2,4,6-trichlorophenyl)oxalate-hydrogen p eroxide system. Dynamic ranges from 60 ng l(-1) to 400 mu g l(-1), limits o f detection at the nanogram-per-litre level and relative standard deviation s from 2.2 to 5.0% were thus obtained for the amines. The proposed method s urpasses other chromatographic alternatives based on different detection te chniques in terms of limits of detection. Also, it affords routine analyses of environmental waters containing low-molecular-mass amines at trace leve ls. (C) 1999 Elsevier Science B.V. All rights reserved.