凝胶渗透色谱净化-气相色谱/串联质谱分析蘑菇中的36种农药残留

建立了用凝胶渗透色谱净化-气相色谱/串联质谱分析蘑菇中36种农药残留的方法。蘑菇中的待测农药组分在30 ℃条件下用乙酸乙酯提取,高速匀浆后通过凝胶渗透色谱净化;选用填料为中性多孔的聚苯乙烯二乙烯基苯微球体的S-X3玻璃柱(22 g,19 cm×2 cm)作为凝胶渗透色谱净化柱,流动相为乙酸乙酯-环己烷(体积比为1∶1)溶液,流速5 mL/min;收集第7~15 min流出的液体用气相色谱-三重四极杆串联质谱仪测定。在0.01~1.0 mg/L的质量浓度范围内,各种农药标准溶液的线性相关系数均大于0.99。在样品中添加36种农药(添加水平为0.01,0.05,0.10 mg/kg)的混合标准溶液,平均回收率为72.6%~117.1%,相对标准偏差为2.0%~10.8%(n=5),最低检出限为 0.1~0.7 μg/kg,最低定量限为 0.2~2 μg/kg。

Determination of 36 Pesticide Residues in Mushroom by Gel Permeation Chromatography and Gas Chromatography- Tandem Mass Spectrometry

A gel permeation chromatographic method was developed for the extraction of 36 pesticides from mushroom prior to gas chromatography with a triple quadrupole mass spectrometric determination. The extraction was based on homogenization with ethyl acetate using a high speed homogenizer. A gel permeation chromatographic clean-up process with ethyl acetate-cyclohexane (1:1, v/v) as mobile phase was applied to the extracts to separate the low-molecular mass pesticides from the high molecular mass compounds in the mushroom. The 7-15 min eluate fraction was collected for subsequent analysis. The target compounds were quantified in the final extract by gas chromatography using a triple quadrupole mass spectrometer with multiple reaction monitoring (MRM). In the linear range (0.01-1.0 mg/L) of each pesticide, the correlation coefficient was higher than 0. 99. The average recoveries (spiked at the levels of 0.01, 0.05, 0.10 mg/kg) were from 72.6% to 117.1% with the relative standard deviations from 2. 0% to 10. 8% (n=5). The limits of detection (LOD) for these pesticides were from 0. 1 to 0.7 microg/kg and the limits of quantification (LOQ) were from 0.2 to 2 Lg/kg.