Abstract:A high-throughput method based on UPLC-MS/MS was developed for the determination of 44 mycotoxins in longan and its products. The samples were extracted with 80% acetonitrile-water (V/V) solution containing 1% acetic acid, and purified by PSA and C18. A Waters ACQUITY UPLC BEH C18 column was used for separation, with 0.2% FAacetonitrile and water-acetonitrile as the mobile phase for gradient elution. Quantification was performed using the internal standard method under MRM mode with positive and negative electropry ionization. Results showed that a good linear relationship was found for the 44 mycotoxins, with the correlation coefficients ≥ 0.990 41, the limit of detection ranging within 0.003~0.7 μg/kg, and the limit of quantification being 0.01~2.0 μg/kg. The relative standard deviation (RSD) was 0.7%~9.7% (n=6), and the recoveries of the 44 mycotoxins at three spiking levels (low, intermediate and high levels) ranging within 70.7%~123.6%. The analyses of the 17 batches of longan and its products purchased from market revealed that the positive rate was 100%, with the concentrations of mycotoxins like 15-ADON, Fus X, PAT, TeA were relatively higher, indicating that they were the main contaminated mycotoxins during the growth, storage and processing processes of longan. Hazard Quotient (HQ) was used to assess the dietary exposure risk The assessment results showed that the HQ values of 21 mycotoxins were 0~0.012 37, which were all lower than 1, indicating no risk and little threat to human health.
