蔬菜水果中有机磷和氨基甲酸酯气相色谱-质谱选择离子测定

Determination of organophosphorus and carbamate pesticides in vegetables and fruits by gas chromatography-mass spectrometry and selected ion monitoring

目的：建立一种测定蔬菜水果中有机磷和氨基甲酸酯农药残留的气相色谱质谱方法。方法：采用乙腈超声提取蔬菜水果中有机磷和氨基甲酸酯农药，80℃水浴氮气吹至近干，以丙酮溶解，以自制弗罗里硅土、活性炭、氧化铝柱净化，以气相色谱-质谱选择离子监测方式分析检测12种有机磷和4种氨基甲酸酯农药残留。结果：所有16种农药均在14min内流出，分离良好，农药标准的线性范围在0．01-15μg／ml，相关系数r均在0．99以上，低、高二种浓度加标回收率均在65．3％-108．2％之间，相对标准偏差均小于20％，方法最低检出限在0．002-0．15μg/ml（S／N=3）。结论：方法适合于蔬菜和水果中有机磷和氨基甲酸酯农药的测定。

Objective：To establish a method for determination of organophosphorus and carbamate pesticides in vegetables and fruits by gas chromatography-mass spectrometry （GC-MS） and selected ion monitoring （ SIM ）. Methods： The pesticides were extracted with acetonitrile by ultrasonic wave. The extract was warmed with water at 80℃ and blowed with nitrogen gas until it was nearly dry. Then it was dissolved in acetone and cleaned-up by florisil -charcoal -alumina glass column. The analysis was per-formed by GC-MS and SIM. Retention time and specific ions were used to confirm the pesticides. Results：The calibration curves of 16 pesticides were linear （correlatiom coefficient r〉0.99） within the range of 0.01-15μg/ml. The recoveries were 65.3%-108. 2% ,the relative standard deviations （RSD） of the method was 〈 20% for each case, and the limit of determination （ LOD）, defined in termes of 3 times baseline noise was 0. 002-0.15 μg/ml. Conclusion：The method is suitable for determining pesticides in fruits and vegetables.