A simple and effective method for the determination of chlorantraniliprole and spirodiclofen in tobacco by liquid chromatography after accelerated solvent extraction and silica gel clean-up

摘要

A new method for the determination of chlorantraniliprole (CAP) and spirodiclofen (SDF) residues in tobacco was developed by using liquid chromatography with diode-array detection (LC-DAD) after accelerated solvent extraction (ASE) and silica gel cleanup. The conditions of ASE, silica gel cleanup, and LC were investigated and optimized. A Waters C18 column (250 × 4.6 mm ID, 5 μm) was used for the LC using a mobile phase composed of methanol and water (90:10, v/v). Under optimal conditions, the linearity was satisfactory in the range of 0.03-1.5 μg/mL with a correlation coefficient of 0.9994 for CAP and 0.13-2.5 μg/mL with a correlation coefficient of 0.9991 for SDF. The method limit of quantification (LOQ) was 16.5 μg/kg for CAP and 64.3 μg/kg for SDF, which is lower than their maximum residue limits (MRLs). The recoveries were 88.5-102% with relative standard deviations (RSDs) of 2.7-6.9% for CAP, and 87.7-98.5% with RSDs of 1.8-5.9% for SDF. The proposed method is simple, rapid, effective, and provides the sensitivity and linearity necessary for analysis of the pesticides in tobacco.