气相色谱-串联质谱(GC-MS/MS)法测定茶叶中20种农药残留

Determination of 20 kinds of pesticide residues in tea by GC-MS/MS

本文建立了气相色谱-串联质谱(GC-MS/MS)同时测定茶叶中多种药物残留的方法。样品加入正己烷作为提取液,经石墨化炭固相萃取小柱净化,待测物在气相色谱-串联质谱(GC-MS/MS)上测定,以保留时间和特征离子对定性,外标法定量。分析物质在50-500μg/L线性关系良好,定量离子对的相关系数大于0.99。分析物在添加水平为0.01-0.10 mg/kg时,回收率范围在70.0%-110.0%,相对标准偏差为5.0%-11.0%,符合残留分析要求。分析物质的定量下限(S/N>10)为0.01 mg/kg。该方法快速、灵敏、准确,各项技术指标均满足国内外农药残留监测限量标准要求,能够很好的应用于茶叶中痕量农药的残留测定。

A method for the determination of multi-pesticide residues in tea was developed by GC-MS/MS. The samples added n-hexane as extractive liquid, purified with solid - phase extraction （ SPE）, and tested by tandem mass spectrometry （GC-MS/MS）. The results showed that the linearity relationship of paraquat was well in 50 -500 μg/ L, and the correlation coefficient of quantitative ion was more than 0.99. When the limit of quantification （ LOQ, S/ N 〉 10） of the samples was 0.01 -0.10 mg/kg, the average spiked recoveries ranged from 70.0% to 110.0% , and the relative standard deviations （ RSDs, n = 6） were in 5.0% - 11.0%. The method, with performance of quick, easy, effective, sensitive and accurate, could be used for the daily monitoring of paraquat in tea.