气相色谱-质谱联用法测定植物性食品中硫丹

Determination of endosulfan in phytogenic foods by gas chromatography-mass spectrometry

目的 建立气相色谱-质谱联用法测定植物性食品中硫丹及其代谢物残留量。方法 取可食用部分样品,经粉碎后,乙腈超声提取,无水硫酸钠脱水,低温离心,上清液经氨基柱净化,60℃水浴氮吹浓缩至近干,正己烷定容,过0.22μm滤膜。1μl进样,DB-1701(60 m×0.25 mm,0.25μm)色谱柱分离,采用气相色谱-质谱选择性离子扫描方式检测。以保留时间和离子丰度比综合定性,外标法定量。结果 在优化的实验条件下,硫丹在0.02μg/ml~1.00μg/ml内线性关系良好,相关系数均≥0.999 6,检出限为0.4μg/kg~0.9μg/kg,定量限为1.2μg/kg~2.7μg/kg,回收率为85.4%~115.2%,相对标准偏差为2.9%~9.1%。测定30件蔬菜及水果样品,均未检出α-硫丹、β-硫丹、硫丹硫酸酯。结论 该方法具有较高的准确度和稳定性,灵敏度高,适用于植物性食品中硫丹及其代谢物残留量的检测。

Objective To establish a method for the determination of endosulfan and its metaboites residues in phytogenic foods by gas chromatography-mass spectrometry.Methods After the edible part of the sample was crushed,it was ultrasonically extracted with acetonitrile,then dehydrated with anhydrous Na_(2)SO_(4),and centrifuged at low temperature.The supernatant was purified by amino acid column.The eluent was nearly dried-up under nitrogen blowing in 60 ℃ water bath,then redissolved withn-hexane,and filtrated with 0.22 μm filter membrane.Finally 1 μl of the sample was injected for analysis.The target analytes were separated with DB-1701(60 m × 0.25 mm,0.25 μm) and detection was performed using gas chromatography-mass spectrometry selective ion scanning.The qualification was based on retention times and ion abundance ratio,and the external standard method was used for quantification.Results The linearity of the method was within 0.02 μg/ml-1.00 μg/ml,with the correlation coefficients ≥0.999 6.The detection limits of the method were within 0.4 μg/kg-0.9 μg/kg and their limits of quantification were within 1.2 μg/kg-2.7 μg/kg,and the recovery rates were within 85.4%-115.2%,with the relative standard deviations of 2.9%-9.1%.No α-endosulfan,β-endosulfan and Endosulfan sulfate were detected in 30vegetable and fruit samples.Conclusion This method is accurate,reliable,and sensitive,which is suitable for the determination of endosulfan and its metaboites residue in phytogenic foods.