QuEChERS-气相色谱法测定果蔬中10种有机磷类农药残留

Determination of 10 Organophosphorus Pesticide Residues in Fruits and Vegetables by QuEChERS-Gas Chromatography

目的:建立QuEChERS-气相色谱法同时测定果蔬中10种有机磷类农药残留量的方法。方法:果蔬样品经清洗、组织捣碎、乙腈提取、QuEChERS净化和丙酮定容,经色谱柱分离后进入气相色谱FPD检测器进行定性、定量检测。结果:在DM-5色谱柱上甲胺磷和敌敌畏分离效果不好,倍硫磷和毒死蜱峰重叠,而10种有机磷农药在Rtx-1701色谱柱上均能达到很好的分离效果;10种有机磷农药在0.25~4.00 mg/mL线性良好,方法检出限在0.001~0.006 mg/kg,加标回收率为75.2%~96.5%,相对标准偏差在1.8%~5.1%。结论:该方法分离效果好,检测准确度高,重复性良好,达到了农药残留检测的要求,适用于果蔬中多种有机磷类农药残留的同时测定。

Objective:To establish a method for the determination of 10 organophosphorus pesticides in fruits and vegetables by QuEChERS and gas chromatography.Method:After cleaning,tissue mashing,acetonitrile extraction,QuEChERS purification and acetone constant volume,the fruit and vegetable samples are separated by chromatographic column and then enter gas chromatography FPD detector for qualitative and quantitative detection.Result:The separation effect of methamidophos and dichlorvos on DM-5 column is not good,and the peaks of fenthion and chlorpyrifos overlap,while 10 organophosphorus pesticides can achieve good separation effect on Rtx-1701 column.The linearity of 10 organophosphorus pesticides was good in the 0.25~4.00 mg/mL.The detection limit was 0.001~0.006 mg/kg,the recovery was 75.2%~96.5%,and the relative standard deviation was 1.8%~5.1%.Conclusion:The method has good separation effect,high detection accuracy and good repeatability,and meets the requirements of agricultural residue detection.It is suitable for the simultaneous determination of multiple organophosphorus pesticide residues in fruits and vegetables.