High-throughput determination of multi-mycotoxins in Chinese yam and related products by ultra fast liquid chromatography coupled with tandem mass spectrometry after one-step extraction

A simple, accurate and sensitive ultra fast liquid chromatography coupled with tandem mass spectrometry (UFLC-MS/MS) method was developed for high-throughput determination of aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), fumonisins (FB1 and FB2) and zearalenone (ZEA) in Chinese yam, yam flours and yam-derived products. Mycotoxins were extracted from the samples with methanol-water-formic acid (79:20:1, v/v/v) and no further cleanup step before analysis. After optimization of some crucial parameters including sample preparation, chromatographic separation and MS/MS conditions, the method was successfully validated to exhibit excellent performance in terms of satisfactory linearity (r≥0.9977), limits of detection (≤0.15ngmL(-1)) and quantification (≤0.5ngmL(-1)) with good precision (RSD for intra- and inter-day variations of ≤4.65% and 6.31%, respectively), good accuracy (recoveries of 71.0-106.0%) and robustness, together with short run time (8min/sample). The developed method was applied for simultaneous detection and quantification of the above 8 mycotaxins in 27 batches of Chinese yam and related products collected from different markets and pharmacies in China. The results revealed that 1 normal sample and 4 moldy samples were found to be contaminated with different mycotoxins. The detected concentrations of AFB1 in 2 moldy samples exceeded the regulatory maximum residue levels. The proposed method was capable for simultaneous determination of mycotoxins in this and other types of complex matrices.