气相色谱-负化学离子源质谱联用法测定植物性产品中多组分农药残留量

Multiresidue determination of pesticide residues in vegetable food by gas chromatography-negative chemical ionization mass spectrometry

通过气相色谱埙化学离子源质谱技术建立了同时检测18种农药残留的分析方法。样品经正己烷和丙酮混合溶剂及正己烷提取后，用活性炭-中性氧化铝混合小柱净化，再由气相色谱埙化学离子源质谱分时段选择离子监测技术进行测定。一次进样就能得到18种农药残留结果；各农药在0．005、0．01和0．02mg／kg 3个添加水平的平均回收率在70．2％～115．3％之间，RSD〈12％，检出限为0．01～6ug／kg，方法可应用于8种植物性产品中的农残检测。

A gas chromatography（GC）-negative chemical ionization mass spectrometry （NCI-MS） method was proposed for analyzing 18 kinds of pesticides in vegetable food. Pesticide residues were extracted from samples with acetone and n-hexane. A SPE column （ENVI-Carb 0.25 g, 3 mL） with 0.5 g neutral aluminum oxide on the top of the cartridge was used for purification. Analytical screening was determined by the technique of gas chromatography-negative chemi- cal ionization mass spectrometry-selected ion monitoring. The recoveries of all pesticides were in the range of 70.2% 115.3% at three spiked levels of 0. 005, 0.01 and 0.02 mg/kg, and the relative standard deviations were below 12%. The limits of detections of all pesticides were from 0.01 to 6ug/kg.