改进的石墨烯分散固相萃取-液相色谱-串联质谱法测定茶叶中15种氨基甲酸酯类农药的残留量

摘要

目的 以石墨烯为吸附剂,建立分散固相萃取-液相色谱-串联质谱法测定茶叶中多种氨基甲酸酯类农药残留量.方法 样品采用水浸泡、乙腈提取,石墨烯作为吸附剂祛除杂质后,液相色谱-串联质谱仪测定,外标法定量.结果 15种氨基甲酸酯类农药在0.001～0.02 μg/mL范围内线性良好,相关系数均大于0.990,且定量限均可达到0.01 mg/kg.空白样品在0.01、0.02和0.10 mg/kg 3个添加水平下,回收率范围为61％～106％,相对标准偏差为4.6％～13％.结论 本方法操作简便、快速、成本较低,适用于茶叶中氨基甲酸酯类农药的检测.%Objective To establish a method for determination of 15 kinds of carbamate pesticides in tea by liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with dispersive solid-phase extraction using graphene as adsorbent.Methods The samples were rehydrated,extracted with acetonitrile,and cleaned up by graphene.The determination was carried out by LC-MS/MS with external standard method for quantification.Results The calibration curves were linear in the range of 0.001～0.02 μtg/mL with the correlation coefficients above 0.990,and the limits of quantification for 15 kinds of carbamate pesticides were 0.01 mg/kg.The spiked recoveries for 15 kinds of carbamate pesticides were in the range of 61％～106％ at 3 spiked levels of 0.01,0.02 and 0.10 mg/kg,with the relative standard deviations of 4.6％～13％.Conclusion This method is simple,rapid and less expensive,which is suitable for the determination of carbamate pesticides in tea.