Simultaneous determination of zearalenone and its derivatives in edible vegetable oil by gel permeation chromatography and gas chromatography-triple quadrupole mass spectrometry.

A sensitive gas chromatographic-triple quadrupole mass spectrometric (GC-QqQ MS) analytical method, for the determination of zearalenone and its five derivatives in edible vegetable oil, was developed. After the vegetable oil samples were prepared using gel permeation chromatography, the eluent was collected, evaporated and dried with nitrogen gas. The residue was silylated with N,O-bis-trimethylsilyltrifluoroacetamide, containing 1% trimethylchlorosilane. GC-QqQ MS was performed in the reaction-monitoring mode to confirm and quantify mycotoxins in vegetable oil. The limits of quantitation were 0.03-0.2 μg kg(-1) for the six mycotoxins. The average recoveries, measured at 2, 20 and 200 μg kg(-1), were in the range 80.3-96.5%. Zearalenone was detected in the range 5.2-184.6 μg kg(-1) in nine maize oils and at 40.7 μg kg(-1) in a rapeseed oil from the local market.