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

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-TOF-MS) 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 mu g kg(-1), and limits of quantification ranged from 0.1 to 200 mu g 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, 0-2.01x10(4), 0-6.94x10(3) and 0-3.05x10(3) mu g kg(-1), respectively.