Abstract:

Matrix effects and their influencing factors in the determination of pesticide residues in edible fungi by high
performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) were studied. In order to eliminate
matrix components, three different purification methods namely solid phase extraction on an amino column, quick, easy,
cheap, effective, rugged, safe (QuEChERS) extraction and no treatment were comparatively evaluated. Purification with
QuECHERS method was demonstrated to be enough to eliminate most of the matrix effect. We found that matrix effects
were influenced by sample matrix, and the types and concentrations of pesticide. The results showed that shiitake exhibited
the strongest matrix effects whereas the matrix effects from oyster mushroom were the weakest among six different matrixes.
Moreover, the lower the concentrations of the pesticides analyzed were, the stronger matrix effects were. A dilution
procedure was demonstrated to be enough to eliminate most of the matrix effects when also taking into account sensitivity
and the limit of detection of the instrument.

Key words: edible fungi, matrix effects, pesticide residues, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), QuEChERS