Development of a sensitive and robust liquid chromatography coupled with tandem mass spectrometry and a pressurized liquid extraction for the determination of aflatoxins and ochratoxin A in animal derived foods

Abstract

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) with a pressurized liquid extraction (PLE) was developed for the simultaneous determination of aflatoxins B₁, B₂, G₁, G₂, M₁ and M₂, and ochratoxin A in the muscle, liver, kidney and fat of swine, bovine and sheep, muscle and liver of chicken, muscle and skin of fish, as well as in hen eggs and dairy milk. Samples were extracted with PLE and cleaned-up with solid phase extraction (SPE) on HLB cartridges. The optimum extraction conditions were obtained as a 11 ml ASE cell, acetonitrile/hexane as the extraction solvent, 1500 psi, 100 °C, a 5 min static time and a 60% flush volume. A cheaper and widely used SPE column (Oasis HLB) was applied during clean up. The detection and quantification of the 7 mycotoxins were performed by a reversed-phase liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry (LC/ESI-MS/MS). The limits of detection defined as CCα varied from 0.07 μg/kg to 0.59 μg/kg. The recoveries of spiked samples from 0.25 μg/kg to 1 μg/kg ranged from 68.3% to 105.7% with the relative standard deviations of less than 17.6%. Performances of the whole analytical procedure met the criteria established by the European Commission for mass spectrometric detection.