Determination of the cross-reactivities for alpha-zearalenol, beta-zearalenol, zearalanone, alpha-zearalanol, and beta-zearalanol on three commercial immunoaffinity columns targeting zearalenone.

Immunoaffinity extraction has become increasingly important as a sample preparation and cleanup method in mycotoxin analysis. In this study, the antibody specificities of 3 commercial immunoaffinity columns (IACs) targeting zearalenone (ZON) were compared for alpha-zearalenol, beta-zearalenol, zearalanone, alpha-zearalanol, and beta-zearalanol. The recoveries of ZON and its 5 analogs were determined in triplicate when extracted from 10 mL circumneutral river water samples spiked with 20 ng analyte individually or in a mixture. The analytes were analyzed by means of electrospray ionization liquid chromatography/tandem mass spectrometry using deuterated internal standards for quantitation. Recoveries ranged from 69 to 115% for all analytes with relative standard deviations of 1-39%. Cross-reactivities for the analogs were > 80% when applied both individually and in a mixture. No significant competition effects were observed when the compounds were applied as a multianalyte mixture well below the stated IAC capacities. The results obtained here demonstrate that all IACs tested are highly cross-reactive towards the 5 ZON derivatives and may be applied for their simultaneous extraction or cleanup.