Abstract
Multiresidue method for fast determination of pesticides in fruit juices by ultra performance liquid chromatography coupled to tandem mass spectrometry
A new analytical method for the simultaneous determination of 90 pesticides in fruit juices by ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) has been developed and validated. Extraction was performed with acetonitrile, applying QuEChERS methodology, and the extracts were analyzed without any further clean-up step, providing better results than solid phase extraction (SPE) procedure. Before chromatographic step, extracts were diluted with water (1:1) in order to obtain good peak shapes. Several chromatographic conditions were evaluated in order to achieve a fast separation in Multiple Reaction Monitoring (MRM) mode, obtaining a run time of only 11 min. Matrix effect was studied for different types of fruit juices (peach, orange, pineapple, apple and multifruit), indicating that multifruit juice can be selected as representative matrix for routine analysis of these food commodities. Pesticides were quantified using matrix-matched calibration with recoveries between 70.4 and 108.5 % and relative standard deviation lower than 20 %. Limits of quantification were lower than 5 µg L(-1) in all the cases. The developed procedure was applied to commercial fruit juices, detecting carbendazim, cyprodinil and thiabendazol in a few samples.