Determination of pesticide residues in chilli and Sichuan pepper by high performance liquid chromatography quadrupole time-of-flight mass spectrometry

In this study, a multi-component analytical method for the detection of pesticide residues in chilli and Sichuan pepper by high performance liquid chromatography coupled with quadrupole time of flight mass spectrometry (LC-Q-TOF/MS) was developed and validated. The sample preparation is based on an extraction step with acetonitrile followed by a cleanup step using primary secondary amine, C-18, graphitized carbon black and anhydrous magnesium sulfate. Values of matrix effects ranged from 55.8 to 26.0 % for chilli, and -69.1 to 24.0 % for Sichuan pepper. The LOQ of < 5 mu g kg(-1) was achieved for all the target pesticides. Applying the method to real samples, some pesticides were found at high concentrations, which were beyond the MRL set by the EU. The results showed that the developed method could be used for the quantitative analysis of target pesticides and non-target screening for potential metabolites in chilli and Sichuan pepper.