Comparison of two post-column derivatisation systems, ultraviolet irradiation and electrochemical determination, for the liquid chromatographic determination of aflatoxins in food
This study compared two post-column derivatisation (PCD) techniques for the determination of aflatoxins B1, B2, G1, and G2 (AFB1, AFB2, AFG1, and AFG2) by fluorescence detection after liquid chromatographic separation: ultraviolet (UV) irradiation (PCD(UV)) and electrochemical bromination (PCD(EC)). Photochemical fluorescence enhancement was obtained with 2 different commercially available systems (PCD(UV1) and PCD(UV2)). An electrochemical bromination apparatus was used for bromination. Analyses of naturally contaminated or spiked samples of corn, pistachio paste, peanut butter, fig paste, and animal feed showed that neither of the techniques resulted in derivatisation- specific matrix interferences for any of the matrixes under study, even when extracts were not completely purified. The response ratios PCD(UV)/PCD(EC) for AFB1, AFB2, AFG1, and AFG2 were 0.86, 0.96, 0.70, and 0.96, respectively, for PCD(UV1) and 0.82, 0.95, 0.60, and 0.90, respectively, for PCD(UV2). The long-term use of the UV lamps (300h for PCD(UV1) and 343h for PCD(UV2)) in the photochemical detectors showed that these ratios remained stable throughout the time frame investigated. The relative standard deviation obtained for each of the devices during the in-house validation study ranged from 0.3 to 1.8% for PCD(UV1), from 0.8 to 1.3% for PCD(UV2), and from 0.9 to 2.0% for PCD(EC).
Bibliographic Reference: An article published in: Journal of AOAC International, Vol.85, No.2, (March/April 2002), pp.411-415
Availability: Reprints of this article can be ordered from the AOAC International website at: http://www.aoac.org/pubs/JOURNAL/years.htm
Record Number: 200214814 / Last updated on: 2002-06-20
Original language: en
Available languages: en