免疫亲合柱净化-气相色谱质谱法测定花生和大蒜中乙草胺残留量

Determination of Acetochlor Residue in Peanut and Garlic by Gas Chromatography-Mass Spectrometry After Purification by Immunoaffinity Chromatography

目的建立花生和大蒜中乙草胺的残留分析方法。方法试样中的乙草胺用甲醇提取,经乙草胺免疫亲合柱净化后,用气质联机方法在选择离子监测模式下分析检测。结果最低检测限为5ng/g。在10、20、40ng/g3个添加水平,花生试样的平均回收率为94.6%～106.3%,相对标准偏差为4.7%～8.9%,大蒜试样的平均回收率为97.2%～105.2%,相对标准偏差为3.8%～7.4%。结论方法检测结果准确可靠,符合定量要求,前处理方法重复性好,速度快,可以用于花生和大蒜实际样品的日常检测。

Objective To determine acetochlor residue in peanut and garlic by gas chromatography-mass spectrometry after purification by immunoaffinity chromatography.Method The acetochlor of samples were extracted with methanol and then purifyied with immunoaffinity chromatography,and determined by gas chromatography-mass spectrometry at the selected ion monitoring mode.Results The limit of determination was 5 ng/g.The average recoveries ranged from 94.6%～106.3% for peanut when fortified 10,20,40 ng/g and the relative standard deviations were from 4.7% to 8.9%.The average recoveries ranged from 97.2%～105.2% for garlic at the same level and the relative standard deviations were from 3.8% to 7.4%.Conclusion The method could be accurate,reliable,rapid and repetitive and could be applied to determine acetochlor in peanut and garlic.It could meet the requirements for quantitative determination.