Determination of HT-2 and T-2 toxins in oats and wheat by ultra-performance liquid chromatography with photodiode array detection

Abstract

European intake estimates indicate that the presence of HT-2 and T-2 toxins in cereals, mainly in oats, can be of concern for human health. Therefore, the development of sensitive, rapid and reliable methods for determining these mycotoxins in cereals, in particular oats, has high priority. A rapid ultra-performance liquid chromatographic (UPLC) method has been developed for the simultaneous determination of HT-2 and T-2 toxins in oats and wheat at μg kg(-1) level. Ground samples were extracted with methanol/water (90:10, v/v) and the diluted extracts were cleaned up through immunoaffinity columns. HT-2 and T-2 toxins were separated and quantified by UPLC with photodiode array (PDA) detector (λ=202 nm) in less than 5 min. Mean recoveries from blank oats samples spiked with HT-2 and T-2 toxins at levels of 50-1000 μg kg(-1) ranged from 87 to 96%, with relative standard deviations (RSDs) lower than 7%; mean recoveries from wheat spiked with HT-2 and T-2 toxins at levels of 25-100 μg kg(-1) ranged from 91 to 103%, with RSDs lower than 5%. The limit of detection of the method was 8 μg kg(-1) for both toxins (signal-to-noise ratio 3:1). The method was successfully applied to the analysis of HT-2 and T-2 toxins in naturally contaminated oats and wheat samples. A good correlation was found by comparative analysis of naturally contaminated samples of oats (r=0.9985) and wheat (r=0.9058) using the proposed method or a reliable HPLC method with fluorescence detection after pre-column derivatization with 1-anthroylnitrile.