气相色谱法测定水稻中的丁草胺和草酮的残留量

Determination of Butachlor and Oxadiazon Residues in Rice by GC

【目的】建立稻米、谷壳、植株中同时测定丁草胺和嗯草酮残留量的气相色谱分析方法。【方法】稻米、谷壳样品均采用乙腈提取，植株样品采用乙腈一水（体积比2：1）提取，PsA和多壁纳米碳管净化，气相色谱-pEcD测定。【结果】对样品中的丁草胺、嗯草酮进行不同水平添加回收率试验，方法的平均回收率为70．7％-105．5％，相对标准偏差（RSD）小于20．1％，最低检测质量分数均为0．005mg＆g。【结论】稻米中丁草胺和日恶草酮的残留量均低于我国最大允许残留限量，方法的灵敏度、准确度和精密度均符合农药残留分析要求。

[Aims] A new method was developed for residual analysis of butachlor and oxadiazon in brown rice, husk, and straw by gas chromatography （GC）. [Methods] The samples of brown rice and husk were extracted by acetonitrile, the samples of straw were extracted by acetonitrile and water （2 ： 1, by vol）, cleaned up by MWCNTs and PSA （primary secondary amine）, and then determined by GC-tECD. [Results] The average recoveries of the method ranged from 70.7-105.5%, the relative standard deviations were less than 20.1%. The limit of determination of butachlor and oxadiazon in rice samples were both 0.005 mg/kg. [Conclusions] The residues of butachlor and oxadiazon in rice were below the MRL in China. The method had high sensitivity, accuracy and precision, and met with the requirements for pesticide residue analysis.