Comparison and improvement of the existing methods for the determination of aflatoxins in human serum by LC-MS/MS

Aflatoxins are toxic metabolites of some Aspergillus flavus, A. parasiticus and A. nomius strains that occur in many foods and feeds. Aflatoxin B-1 is the most abundant and toxic member of the family, and it is also the most potent hepatocarcinogen known. In order to estimate the potential human health risk of aflatoxin B-1, it is useful to measure its blood concentration. In this work a rapid liquid chromatography coupled to mass spectrometry (LC-MS/MS) method for the simultaneous determination of aflatoxins B-1, B-2, G(1) and G(2) and its metabolites, aflatoxins M-1 and M-2 in human serum, is proposed. Small serum volumes have been used and the extracts have been obtained without any clean-up procedure. The isolation of the aflatoxins from human serum was achieved using subsequent pH-controlled solvent extractions steps. Recovery rates in the range between 31 and 98% were achieved in the serum, while the limits of detection and quantification for the proposed method were 0.5 ng mL(-1) and 1.0 ng mL(-1), respectively. The validation of the method has been demonstrated by analysing spiked and naturally contaminated blood serum.