Multiresidue method for determination of pesticides in coconut (Cocos nucifera Linn.) endosperm by using GC–MS/MS and UHPLC–MS/MS analysis

Abstract

Several pesticides are used in the cultivation of coconut palm, hence evaluation of the residues from these substances must be analyzed in the fruit, to provide and ensure the food safety. Therefore, the development and validation of comprehensive and effective methods becomes crucial, given the complexity of the matrix. Thus, a novel method was developed for the determination of 10 different pesticides residues in coconut endosperm. QuEChERS showed to be an efficient method for sample preparation to overcome the complexity of the matrix. To extend the analytical scope, including a wide range of polarities, ultrahigh-performance liquid chromatography coupled mass spectrometry (UHPLC-MS/MS) and gas chromatography coupled mass spectrometry (GC--MS/MS) were employed. Triple quadrupole spectrometer was used in selected reaction monitoring (SRM) on both detectors, providing high sensitivity and selectivity. These approaches showed to be optimal, considering the parameters of linearity (r ≥ 0.99), matrix effect (0–50 %), LOQ (5 μg kg−1, except for thiamethoxam (20 μg kg−1)), specificity, trueness (60–118 %) and precision (repeatability and within-laboratory reproducibility) ≤ 20 %. The concentration levels obtained were higher than the MRL recommended for thiamethoxam (EU regulation <10 μg kg−1), justifying the analysis of such residues in commercial coconut endosperm.