气相色谱-质谱法测定莲子中农药残留的一测多评研究

Study on the simultaneous measurement of residual level of three pesticides in nelumbinis semen using GC-MS/MS

目的建立气相色谱一质谱（gas chromatography-masss pectrometer,GC．MS／MS）测定莲子中联苯菊酯等3种拟除虫菊酯类农药残留的一测多评方法。方法采用乙腈提取样品，经CleanertTPH专用净化柱净化。采用GC．MS／MS测定样品，根据色谱相对保留时间和质荷比信息对样品进行定性分析，以联苯菊酯二级离子扫描峰（181．1／166．1）面积为参照峰，计算甲氰菊酯二级离子扫描峰（265．1／210．1）面积、溴氰菊酯二级离子扫描峰（252．9／93．0）面积与其面积之间的相对校正因子，建立以联苯菊酯为对照品，测定莲子中联苯菊酯、甲氰菊酯、溴氰菊酯3种农药残留量的GC．MS／MS方法。结果联苯菊酯、甲氰菊酯、溴氰菊酯进样量在0．01-0．1ng范围内与其色谱峰面积均有较好的线性关系，最低检出限（以进样量计）联苯菊酯为4．321×10^4ng，甲氰菊酯为3．435×10^4ng，溴氰菊酯为8．913×10^-3ng。平均回收率联苯菊酯为93．5％，甲氰菊酯为93．5％，溴氰菊酯为93．8％。结论该方法简便、准确、快速，适用于分析莲子中联苯菊酯、甲氰菊酯、溴氰菊酯3种农药残留情况。

Objective To establish a quantitative method for the simultaneous measurement of the residual level of three pesticides in Nelumbinis semen by GC-MS/MS. Methods The samples were extracted by acetonitrile and purify by Cleanert TPH column. The samples were then tested by GC-MS/MS. Information on relative retention time and mass charge ratio was used for qualitative analysis. The peak area obtained by secondary ion MS of bifenthrin （181.1/166.1）was used as the reference peak to calculate the relative correction factor for the peak area of fenpropathrin （265.1/210.1） and deltamethrin （252.9/93.0）, to establish a method using bifenthrin as the reference substance to determinate there sidual quantity of three pesticides in Nelumbinis semen by GC-MS/MS. Results When the injection quantity of the sample containing bifenthrin,fenpropathrin and deltamethrin in the range of 0.01-0.1 ng, there was a good linear relationship between the injection quantity and peak are a Limitation of quantification （LOQ） of bifenthrin, fenpropathrin and deltamethrin were 4.321×10^-4ng, 3.435×10^4 ng, 8.913×10^-3 ng, respectively. The average recovery rates of bifenthrin, fenpropathrin and deltamethrin were 93.5%, 93.5% and 93.8%, respectively. Conclusions The method of quantitative analysis of multi-components with a single-marker is simple, quick and accurate. It suitable for the detection of residual auantitv of bifenthrin, fenpropathrin and deltamethrin in Nelumbinis semen.