Liquid Chromatographic MS/MS Analysis of a Large Group of Insecticides in Honey by Modified QuEChERS

The analytical tool for analysis of pesticide residues in honey must still be improved. Therefore, a sensitive, selective, rapid, and reliable analytical method for the analysis of pesticide residue belonging to 29 different classes at very low concentration levels was developed. Over 130 insecticides were extracted from the honey matrix using different amounts of sample, concentrations of the extraction solvent, and cleanup sorbents. Acceptable extraction recoveries accounting for matrix effect were obtained using the cleanup sorbent combination chitosan/aluminum oxide/C8 (200/200/200 mg) and 1% FA in ACN. Determinations were made by liquid chromatography-tandem mass spectrometry (LC-MS/MS). For most compounds, the recoveries range from 70 to 120%, with relative standard deviations < 20%. Linear correlation coefficients (r2) were higher than 0.99 at concentration levels of 0.001-0.100 mg kg-1. A positive matrix effect was observed for up to 95% of organophosphates and 43% of pyrethroids and a negative effect for 37% of neonicotinoids. This work showed that the presented method is convenient and reliable for quick monitoring of insecticides in honey samples.