气相色谱法同时测定禾谷类农作物中甲草胺、乙草胺和丁草胺

Simultaneous determination of alachlor,acetochlor and butachlor in cereal crop by gas chromatography

建立气相色谱法同时测定禾谷类农作物中甲草胺、乙草胺和丁草胺3种酰胺类除草剂的分析方法。谷物样品用乙腈、氯化钠超声提取,用弗罗里矽硅土固相萃取柱净化,提取液经0.22μm有机滤膜过滤,以气相色谱(ECD检测器)检测。结果表明,甲草胺、乙草胺和丁草胺的质量浓度在0.1~2.0 mg/L范围内与色谱峰面积呈良好的线性关系,相关系数分别为0.9998,0.9998和0.9996,检出限分别为0.0018,0.0017和0.0013 mg/kg,定量限分别为0.0055,0.0051和0.0040 mg/kg。在加标水平为0.4,2.0和3.6 mg/kg时,3种酰胺类除草剂的平均回收率为90.7%~104.8%,相对标准偏差为0.61%~3.97%(n=6)。该方法准确,灵敏,操作简单,适用于禾谷类农作物中甲草胺、乙草胺和丁草胺残留量的同时测定。

A method for simultaneous determination of alachlor,acetochlor and butachlor in cereal crops by gas chromatography was established.The cereal samples were extracted by ultrasonic with acetonitrile and sodium chloride,and purified with florisil solid phase extraction column.The extracts were filtered with 0.22μm organic membrane,and detected by gas chromatography(ECD detector).The results showed that the mass concentration of alachlor,acetochlor and butachlor had a good linear relationship with the chromatographic peak area in the range of 0.1–2.0 mg/L,and the correlation coefficients were 0.9998,0.9998,0.9996,respectively.The the detection limits of alachlor,acetochlor and butachlor were 0.0018,0.0017 and 0.0013 mg/kg,and the quantitation limits were 0.0055,0.0051 and 0.0040 mg/kg,respectively.When the spiked levels were 0.4,2.0 and 3.6 mg/kg,the average recoveries of the three amide herbicedes were 90.7%–104.8%,and the relative standard deviations were 0.61%–3.97%(n=6).The method is accurate,sensitive,simple which is suitable for the simultaneous determination of the alachlor,acetochlor and butachlor residues in cereal crops.