Analysis of highly polar pesticides and their main metabolites in animal origin matrices by hydrophilic interaction liquid chromatography and mass spectrometry

In this work, a method for the analysis of 14 highly polar pesticides in animal origin matrices by hydrophilic interaction liquid chromatography and mass spectrometry has been described. Three methanol-based extraction procedures with slight modifications, depending on the matrix, have been used. The method has been validated according to the performance criteria from the SANTE guideline for pesticide residues analysis in food and feed. Most of the compounds showed a limit of quantitation at the lowest spike levels tested (0.01–0.02 mg kg⁻¹) in the matrices evaluated. A SPE clean-up step with mixed mode cation exchange sorbent has been used with some matrices, like chicken meat, eggs, liver and kidney, in order to improve the limits of quantification. Glufosinate, glyphosate and HEPA were the compounds which presented more difficulties during the study, due to the lack of sensitivity of the qualifier ions and/or because of the interference from the matrices.