QuEChERS提取-气相色谱法测定蔬菜中的10种有机磷类和氨基甲酸酯类农药残留量

Residues determination of 10 organophosphorus and carbamate pesticides in vegetables by QuEChERS-gas chromatography

目的建立气相色谱法测定蔬菜中的10种有机磷类和氨基甲酸酯类农药残留量的方法。方法样品经组织捣碎、乙腈提取、Qu ECh ERS净化、正己烷定容,配制成10.0μg/ml的混合标准工作液,采用GC检测10种有机磷类和氨基甲酸酯类农药。结果有机磷类农药的LOD为0.001 mg/kg^0.007 mg/kg,LOQ为0.003 mg/kg^0.021 mg/kg;氨基甲酸酯类农药的LOD为0.001 mg/kg^0.004 mg/kg,LOQ为0.003 mg/kg^0.012 mg/kg。平均加标回收率为79.3%~93.1%,相对标准偏差(RSD)为4.9%~15.3%。50份蔬菜样品中,涕灭威检出3份,涕灭威砜检出1份,甲胺磷检出8份,乙酰甲胺磷检出4份,氧乐果检出6份,3-羟基克百威检出1份,其余农药残留指标均未检出。结论该方法灵敏度高,回收率高,检出限低,符合分析要求,适合蔬菜中10种有机磷类和氨基甲酸酯类农药残留检测的要求。

Objective To establish the QuEChERS-gas chromatography（ GC） method for the residues determination of 10 organophosphorus and carbamate pesticides in vegetables. Methods The samples were mashed,extracted with acetonitrile,purified by QuEChERS,constanted volume with hexane,so as to prepare the mixed standard working fluid formulated as 10. 0 μg/ml.10 organophosphorus and carbamate pesticides were detected by GC. Results The LOD and LOQ of organophosphorus pesticides were within 0. 001 mg/kg-0. 007 mg/kg and 0. 003 mg/kg-0. 021 mg/kg. The LOD and LOQ of carbamate pesticides were within 0. 001 mg/kg-0. 004 mg/kg and 0. 003 mg/kg-0. 012 mg/kg,respectively. The average additive recoveries were within 79. 3%-93. 1%,and the relative standard deviation（ RSD） was within 4. 9%-15. 3%. Aldicarb in 3 samples,aldicarb sulfone in one sample,methamidophos in 8 samples,acephate in 4 samples,omethoate in 6 samples,and 3-hydroxycarbofuran in one sample among the 50 samples were detected,and the remaining pesticide residues were not detected. Conclusion The method has high sensitivity,high recovery rate,low detection limit,and could meet the requirement of the detection of 10 organophosphorus and carbamate pesticides in vegetables.