Determination of twenty organophosphates pesticide multi-residues in vegetables and fruits by capillary gas chromatography

Objective:To set up a method for determination of 20 organophosphorus pesticide multi-residues in vegetables and fruits by capillary gas chromatography.Methods:The samples were stirred into homogenate,used acetonitrile to extract the residues,then directly concentrated and injected into gas chromatography with HP-5 Column and flame photometric detector(FPD) for qualification and quantification.Results:The pesticides in vegetables and fruits were separated from each other.The fortified recoveries gained of three spiked levels with 20 organophosphorus pesticide were found 75.6%～113% in cabbage,cucumber and yellow pear.The relative standard deviation(RSD) was 2.8%～17.4%.The minimum detection limit of the method was 0.005～0.087 mg/kg for HP-5 Column,and the retention time was 1.813～16.096 min.Conclusion:This method is simple,rapid,good accurate and of high precision and less cost.So it is suitable for the determination of pesticide multi-residues in vegetables and fruits.