Simultaneous determination of aflatoxins, zearalenone and ochratoxin a in cereal grains by immunoaffinity column and high performance liquid chromatography coupled with post-column photochemical derivatization
Li, J.; Yu, Y.; Tian, M.; Wang, H.; Wei, F.; Li, L.; Wang, X.
Se Pu 24(6): 581-584
ISSN/ISBN: 1000-8713 PMID: 17288138 Accession: 050315512
A method was developed for the simultaneous determination of aflatoxins (AFs) (B1, B2, G1 and G2), zearalenone (ZEA) and ochratoxin A (OTA) in cereal grains by high performance liquid chromatography (HPLC) with fluorescence detection after immunoaffinity column clean-up and post-column derivatization. Cereal grain sample was extracted with methanol-water (80: 20, v/v). The extract was purified by immunoaffinity column and the toxins were separated by reversed-phase HPLC, and quantified with fluorescence detection after photochemical derivatization. The separation was performed on a Nova-Pak column (3.9 mm i. d. x 150 mm, 4 microm, Waters) with a linear gradient of methanol-acetonitrile-1% phosphoric acid mixture. The calibration curves for mycotoxins were made in the concentration range of 0.24 - 6.0 for AFs ( B1, B2, G1 and G2), 4.0 - 100.0 for ZEA and 0.5 - 40.0 microg/L for OTA. Recoveries of the different cereal grains (wheat, rice, rye) spiked with mycotoxins at levels ranged from 0.24 -1.0 microg/kg for AFs (B1, B2, G1 and G2), 4.0 -16.0 microg/kg for ZEA and 0.5 - 3.0 microg/kg for OTA were from 70.8% to 94.0% and relative standard deviations were between 2.79% and 9.38%. The limits of detection were 0.24 Rg/kg for AFs (B1, B2, G1 and G2), 0.5 microg/kg for OTA and 4.0 microg/kg for ZEA.