Gas chromatographic quantification of amino acid enantiomers in food matrices by their N(O,S)-ethoxycarbonyl heptafluorobutyl ester derivatives

Several amino acid enantiomer derivatives were prepared with different chlo roformates and analysed by gas chromatography (GC) on a Chirasil-L-Val GC c olumn, at a temperature below 200 degrees C. Among them the N(O,S)-ethoxyca rbonyl heptafluorobutyl esters presented the best compromise between short retention times, high yield responses and good resolution for almost all th e tested amino acids. These derivatives proved to be suited for quantificat ion of amino acids in aqueous media, with L-p-chlorophenylalanine as intern al standard. The developed procedure was applied to several food samples fo r determination of their free amino acid profiles. (C) 2000 Elsevier Scienc e B.V. All rights reserved.