HISTAMINE AND HISTIDINE DETERMINATION IN TUNA FISH SAMPLES USING HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY - DERIVATIZATION WITH O-PHTHALALDEHYDE AND FLUORESCENCE DETECTION OR UW DETECTION OF FREE SPECIES

A rapid and simple HPLC procedure for the simultaneous determination o f histamine and histidine is presented. Sample extraction, extract pur ification, derivatization and reversed-phase chromatographic determina tion are described. Also the analysis of ''free'' (i.e., not derivatiz ed) species with UV detection is discussed, and the two procedures are compared. A derivatization step involves more difficulties in terms o f linearity and reproducibility because of the great unstability of o- phthalaldehyde derivatives but presents many advantages due to the goo d separation between histamine and histidine as far as the increased s ensitivity is concerned. The first results of canned tuna samples anal ysis are presented and discussed. (C) 1998 Elsevier Science B.V. All r ights reserved.