Use of a modified QuEChERS method for the determination of mycotoxin residues in edible nuts by nano flow liquid chromatography high resolution mass spectrometry

A nanoflow liquid chromatography high resolution mass spectrometry method for the quantification of mycotoxins in nuts has been developed. Two strategies based on QuEChERS methodology were evaluated. Thus, EMR lipid was compared with a conventional mixture of PSA and C18 dispersive solid phase extraction sorbents which have been commonly used in this type of matrices as sample clean-up. The results showed that the use of EMR-lipid reduced more effectively matrix components, achieving a negligible matrix effect for all mycotoxins studied in peanut, pistachio and almond. The proposed method was validated in line with SANTE guidelines using EMR-Lipid as dispersive solid phase extraction sorbent. The lowest concentration level were between 0.05 and 5 mu g kg(-1) , being lower than the maximum levels established by the current legislation. Recovery rates ranged from 75% to 98% was obtained in all sample studied, achieving also satisfactory precision with RSD values lower than 19% in all cases.