Determination of multiresidue pesticides in vegetables and fruits by gel-permeation cleanup and gas chromatography/mass spectrometry

Objective:To establish a method for determination of organophosphorus,carbamate,pyrethroid,organochlorine pesticides in vegetables and fruits by gas chromatography/mass spectrometry(GC/MS) and selected ion monitoring(SIM).Methods: The pesticides were extracted with acetonitrile by ultrasonic wave.The extract was cleaned-up by Auto-Gel-Permeation Cleanup(GPC).The analysis was performed by gas chromatography/mass spectrometry(GC/MS) and selected ion monitoring(SIM).Retention time and specific ions were used to confirm the pesticides.Results: The calibration curves of 34 pesticides were linear(correlatiom coefficient r0.99) within the range of 0.003 μg/ml～10 μg/ml.The recoveries were ranged from 55.3%～128.1%,the relative standard deviations(RSD) of the method was 20% for each case,and the limit of determination(LOD),defined in terms of 3 times baseline noise was 0.006 mg/kg～0.05 mg/kg.Conclusion: The method is suitable for determining pesticides in fruits and vegetables.