Ion trap lC-MS/MS as a valid multi-method to determine trichothecenes and zearalenone in the food industry

Abstract

In recent years the European Scientific Committee on Food has frequently expressed its opinion on Fusarium toxins, setting limits, regulations and guidelines in order to reduce their levels in raw materials and food commodities. Trichothecenes are known as DNA and mitochondrial metabolism inhibitors, representing the largest group (over 170 compounds) of Fusarium mycotoxins. Zearalenone (ZEA) is also produced by Fusarium species. It is found almost entirely in grains and has a mainly oestrogenic effect. Wheat-based products (such as bread and pasta) are the predominant source of deoxynivalenol (DON) and nivalenol (NIV) intake, while the highest amounts of T-2 and HT-2 toxins were observed mainly in oat-based products. Therefore, food companies are progressively being forced to set up analytical methods in their laboratories for determining these kinds of toxins in an accurate, sensitive and rapid way. Following this issue, we set up a liquid chromatography-electrospray ionisation tandem mass spectrometry (LC-ESI-IonTrap-MS/MS) method for the simultaneous determination of several types of A and B trichothecenes, together with ZEA, minimising the matrix effect by using specific fragmentation parameters in positive or negative ion modes and dedicated internal standards: quantification of trichothecenes was done with isotope substituted (13C15)-deoxynivalenol, while quantification of ZEA was performed by the contemporaneous use of Zearalanone (ZAN). Sample extraction was performed with acetonitrile/water mixtures, MycoSep® columns were used for fast and effective clean-up procedure and detection was carried out in the multiple reaction monitoring (MRM) mode. Spiking blank cereal samples, the method was validated in terms of detection limits (reaching µg/ kg levels), linearity, recovery, precision (RSD<5%) and accuracy. Method performances were finally tested on oat and durum wheat samples. In conclusion, ion trap instruments can currently provide high-throughput LC/MSn mycotoxin analysis where sensitivity, reliability and productivity coexist in an interesting and good compromise for food industry applications.