气相色谱法同时测定玉米和土壤中乙草胺和2,4-滴丁酯残留

Determination of Acetochlor and 2,4-D Butyl Ester Residues in Corn and Soil by Gas Chromatography

建立了用气相色谱法同时测定玉米植株、籽粒及土壤中乙草胺和2,4-滴丁酯的残留分析方法。玉米植株、籽粒中的乙草胺和2,4-滴丁酯经石油醚超声波提取,弗罗里硅土柱净化,土壤经二氯甲烷超声波提取,提取液浓缩至干后石油醚定容,气相色谱法电子捕获检测器测定。结果表明,乙草胺在玉米植株、籽粒、土壤中的添加回收率为85.0%～98.6%,相对标准偏差(RSD,n=3)为1.1%～3.4%;2,4-滴丁酯在玉米植株、籽粒、土壤中的添加回收率为83.0%～98.5%,相对标准偏差(RSD,n=3)为0.9%～2.4%。乙草胺和2,4-滴丁酯在样品中的最低检出浓度均为0.01 mg/kg。

An analytical method of acetochlor and 2,4-D butyl ester residues in corn and soil by gas chromatography equipped with an electron-capture detector（GC-ECD） was developed.Corn samples were extracted with petroleum ether and cleaned up with Florisil column,and soil samples were extracted with dichloromethane by ultrasonic method.The fortified recoveries of acetochlor and 2,4-D butyl ester in samples were 85.0%-98.6% and 83.0%-98.5%,respectively.Relative standard deviation was less than 3.4% for acetochlor and 2.4% for 2,4-D butyl ester,and the limit of detection of two pesticides in samples was 0.01 mg/kg,respectively.