Stability and determination of aflatoxins by high-performance liquid chromatography with amperometric detection

A method based on reversed-phase high-performance liquid chromatography (RP-HPLC) with amperometric detection with a glassy carbon electrode at a constant potential of 1.4 V is reported for the separation and identification of aflatoxins B-1, B-2, G(1) and G(2) in a model mixture. The chromatography was performed on a PAH-Baker column with a ternary mobile phase containing methanol, acetonitrile and aqueous LiClO4, electrolyte. Aflatoxin G(1) showed the highest electroactivity in the compound series studied. Calibration curves of aflatoxins G(1) and B-2 were linear up to 0.2 and 0.3 mmol/l, respectively. Sensitivity varied between 7 and 10 ng for the different aflatoxins. The combination of different HPLC detectors in the analysis of these compounds was applied to investigate the stability of aflatoxins G(1) and B-2. (C) 1998 Elsevier Science B.V. All rights reserved.