Development and validation of a QuEChERS based liquid chromatography tandem mass spectrometry method for the...

A reliable and rapid method for the determination of multiple mycotoxins was developed using a QuEChERS (quick, easy, cheap, effective, rugged and safe) based extraction procedure in highly pigmented and complex spice matrices, namely red chilli (Capsicum annum ssp.), black and white pepper (Piper nigrum ssp.). High-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was used for the quantification and confirmation of 17 chemically diversified mycotoxins. Different extraction procedures were studied and optimized in order to obtain better recoveries. Mycotoxins were extracted from the hydrated spices using acidified acetonitrile (1% formic acid), followed by partitioning with NaCl and anhydrous MgSO4; excluding the use of dispersive-solid phase extraction. Significant matrix effect was compensated using the matrix matched calibration curves. Electrospray ionization at positive mode was applied to simultaneously detect all the mycotoxins in a single run time of 20min. Multiple reaction monitoring mode, choosing at least two abundant fragment ions per analyte was applied. Coefficients of determination obtained were in the range of 0.9844-0.9997. Recoveries (ranging from 75% to 117%) were in accordance with the performance criteria required by the European Commission. Intra-day reproducibility ranged from 4% to 22% for most of the mycotoxins. The limit of quantification ranged from 2.3 to 146μgkg(-1). The validated method was finally applied to screen mycotoxins in ten of each spice matrix. Aflatoxins, ochratoxin, fumonisins, sterigmatocystin and citrinin were among the detected analytes. Positive findings were further confirmed using relative ion intensities. The potentiality of the method to be used for confirmatory purposes according to Commission Decision 2002/657/EC was assessed.