POSTCOLUMN DERIVATIZATION FOR SELECTIVE LASER-INDUCED FLUORESCENCE DETECTION IN MICELLAR ELECTROKINETIC CHROMATOGRAPHY OF FATTY-ACID HYDROPEROXIDES

A new method of postcolumn derivatisation in capillary electrophoresis is demonstrated by the reaction of fatty acid hydroperoxides with p-h ydroxyphenylacetic acid (HPAA) to give the fluorescent 'dimer' of HPAA for laser-induced fluorescence detection. This reaction is catalysed by microperoxidase-11 covalently immobilised in a reaction capillary t hat is either spliced or butt joined onto the end of the separation ca pillary. The micellar electrokinetic chromatography of the isomeric hy droperoxides formed by photo-oxidation of oleic, linoleic and linoleni c acids shows that the derivatisation reaction does not lead to signif icant broadening of the peaks. (C) 1998 Elsevier Science B.V. All righ ts reserved.