•  
  •  
 

Abstract

A multiresidue method was developed and validated for the determination of four macrolide pesticides (spinosad, emamectin benzoate, abamectin and milbemectin) and their metabolites in six kinds of vegetables and fruits (Chinese kale, cabbage, eggplant, orange, papaya and strawberry). The pesticide residues were extracted from the samples with acetonitrile/10 mM aqueous ammonium acetate (NH4OAC), pH 4.0 (90:10, v/v) and the purification was carried out with an aminopropyl (NH2) solid-phase extraction cartridge. Reversed-phase high-performance liquid chromatograpy (RP-HPLC) using an ODS-AM column 5 μm, where a gradient elution with methanol/acetonitrile/10 mM aqueous NH4OAc, pH 4.0 mobile phase was employed for the separation and quantification of the pesticides. The method accuracy and precision were determined via recovery experiments and four replicates spiked with three fortification levels (0.15, 1.5, 7.5 μg/g) each. From the overall results of analytes, method LOD values were ranged from 0.01 to 0.03 μg/g, the mean recoveries were in the range of 75-117% and the relative standard deviations (RSD) were lower than 14%. The recovery data from six sample matrices met the acceptability criteria (European Union, SANCO/2007/3131) of recovery (70-120%) and RSD (<20%) at the three levels studied. The simple and efficient method with acceptable performance was thus established for the simultaneous determination of four macrolide pesticides and their metabolites in agricultural products.

Download

Share

COinS