Simplification and Miniaturization of a Multiresidue Method for the Determination of Pesticides in Plant Matrices

A multiresidue method for the determination of pesticides in plant matrices was simplified and scaled down. The unmodified method consists of homogenization with dry ice, extraction with solvent using a blender, and determination by liquid chromatography–tandem mass spectrometry after dilution with aqueous buffer. It was evaluated for several pesticides in different matrices whether the blender extraction could be replaced by a shaker extraction that is the method of choice in residue analysis and enables a higher throughput. The 2 min blender extraction was compared to a 15 min shaker extraction. It was demonstrated that in all experiments that the shaker extraction reached at least equal recovery rates, whereas the relative standard deviation (n = 5) was comparable to the blender extraction. In addition, it was investigated whether the sample weight of 5 g used for analysis in the original method can be reduced to 2 g. The lower mass provided acceptable results for matrices of varying homogeneity. In 11...