Fast determination of multi-mycotoxins in corn by dispersive solid-phase extraction coupled with ultra-performance liquid chromatography with tandem quadrupole time-of-lfight mass spectrometry

摘要

A fast analytical method for the simultaneous determination of 9 mycotoxins, including aflatoxins(B_1, B_2, G_1, and G_2), fumonisins(B_1, B_2 and B_3), zearalenone, and deoxynivalenol in corn using dispersive solid-phase extraction method and ultra-performance liquid chromatography coupled to tandem quadrupole time-of-flight mass spectrometry(UPLC-Q-TOFMS) was developed and validated. Samples were extracted with acetonitrile-water(84:16, v:v, containing 1% acetic acid) using ultrasonic extraction. The extracts were purified with a dispersive SPE method using C18 as a cleaning agent. The final clear extracts were dried by nitrogen blowing and subsequently redissolved in methanol-water(5:5, v:v). The samples were then analyzed by UPLC-Q-TOF-MS with 0.1% formic acid in ammonium acetate-methanol as mobile phase. The mean recoveries were ranged from 68.0 to 120.0%, and the relative standard deviation(RSD) ranged from 0.18 to 6.29%. Limits of detections ranged from 0.05 to 50 μg kg^(-1), and limits of quantification ranged from 0.1 to 200 μg kg^(-1), which were below the legal limits set by the European Union for the legislated mycotoxins. The developed method was applied to 130 corn samples. Among the mycotoxins studied, aflatoxins B_1 and fumonisins B_1, B_2 and B_3 were the most predominant mycotoxins, and their concentrations were 0–593.12, 0–2.01×10~4, 0–6.94×10~3 and 0–3.05×10~3 μg kg^(–1), respectively.