Simultaneous enantiomeric analysis of six chiral pesticides in functional foods using magnetic solid-phase extraction based on carbon nanospheres as adsorbent and chiral liquid chromatography coupled with tandem mass spectrometry.

This work presented a novel method for the simultaneous enantioselective analysis of six chiral pesticides in seven functional foods at enantiomeric levels. Samples were extracted from matrices using a magnetic solid-phase extraction method based on Fe3O4 modified carbon nanospheres as adsorbent. Experimental variables were optimized using one-variable-at-a-time and response surface methodology. Six chiral pesticides were simultaneously enantio-separated under one chromatographic condition using Chiralpak IG column, and a reversed-phase liquid chromatography coupled with tandem mass spectrometry was used for their sensitive and selective quantification. Under the optimum conditions, good linearity was obtained for all enantiomers with correlation coefficients (R2) greater than 0.9912. The mean recoveries of the analytes were in the range of 84.0-105.2%, with intra- and inter-batch precision less than 10.9% and 11.4%, respectively. Method quantification limits varied from 1 to 4 ng g-1 in all the tested matrices. The developed method was successfully applied to real samples to monitor the occurrence and enantiomeric composition of chiral pesticides, demonstrating its applicability for the routine analysis of chiral pesticide residues in food samples.