Based on the methodology of EN 12393, a miniaturized multi-method for the determination of pesticide residues in food products by gas chromatography-mass spectrometry was developed. Using reduced sample weights and solvent volumes, the new method provides a simplified extraction and partitioning step by automatic shaking. Cleanup was performed by gel permeation chromatography on a PSS GRAM 30 Å column followed by a solid-phase extraction with Silicycle SiliaPrep Diamine cartridges that selectively remove fatty acids. The method was validated on four representative matrices (vegetable mixture, orange juice, high fat milk powder and oat flour) for more than 300 pesticides. Recoveries of 70-120% were obtained for most pesticides. Limits of quantitation ranged between 0.01 mg kg-1 and 0.05 mg kg-1. The new method outperforms the original EN 12393 method in terms of solvent consumption, analysis time and cleanup efficiency, while validation results were comparable. Therefore, the method provides an excellent alternative to the existing multi-residue methods for the analysis of different food products.
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