粮谷与油籽中9种二苯醚除草剂残留的气相色谱-质谱法测定

Simultaneous Determination of Nine Diphenyl Ether Herbicides Residues in Cereals and Oilseeds by GC-MS

利用气质联用（GC—MS）技术建立了粮谷与油籽中9种二苯醚除草剂多残留同时检测的方法。粮谷与油籽中二苯醚除草剂残留通过乙腈提取，浓缩后过弗罗里硅土柱净化，采用正己烷-丙酮（体积比6：4）溶液淋洗，淋洗液吹氮至于后以正己烷定容，GC—MS选择离子监测模式（SIM）测定。标准工作曲线线性范围在0．02～1．00mg／L之间，粮谷与油籽中0．01～0．10mg／kg水平二苯醚混标加标回收率在70％～105％之间，相对标准偏差在2．1％～13．6％之间。9种二苯醚除草剂定量下限（106）均小于0．025mg／kg。

A method for simultaneous determination of residues of 9 diphenyl ether herbicides in cereals and oilseeds by GC - MS was presented. The method was based on the extraction of the herbicides residues with acetonitrile and a cleanup with a Florisil column followed by elution with a mixture of nhexane and acetone （6 ： 4 by volume） and GC - MS/SIM detection. The linear ranges of the calibration curves for the nine herbicides residues were 0. 02 - 1.0 mg/L with detection limits varying between 0. 003 mg/L and 0. 009 mg/L. The recoveries of the spiked diphenyl ether herbicides （ ranging from 0.01 -0. 10 mg/kg） in cereals and oilseeds were in the range of 70%- 105%.