茄子中多种农药残留筛查能力验证

Verification of screening ability of multiple pesticide residues in eggplant

通过参加FAPAS(英国分析实验能力验证公司)茄子中多种农药残留筛查能力验证所做的准备工作、基本分析流程和关键操作方法技巧,为其它实验室参加诸如FAPAS农药残留能力验证工作提供经验参考。样品经酸化乙腈(含0.5%乙酸的乙腈,体积分数)提取,分取提取液,氮吹浓缩,乙腈-水(体积比为3∶7)复溶,直接过膜上机检测。HPLC-MS/MS方法以0.1%(体积分数)甲酸水-乙腈为流动相,流量为0.3 mL/min梯度洗脱,采用C_(18)色谱柱进行分离,电喷雾正离子电离(ESI+),多反应监测(MRM)检测,基质匹配外标法定量。重复3次测定结果较为接近,且每次的相对标准偏差(RSD)均小于5.2%,测定结果稳定可靠,Z值在0.3~0.6之间。本次能力验证结果为满意,方法准确度、精密度和灵敏度均符合农药残留检测的要求。

Through the preparations,analysis procedures,operating methods and skills of participating in the FAPAS(Food Analysis Performance Assessment Scheme)multiple pesticide residue screening proficiency test in eggplant,it provided experience reference for other laboratories to participate in the FAPAS pesticide residue proficiency test.The sample was extracted with acidic acetonitrile(containing 0.5%acetic acid,V/V),and then the extracting solution was centrifuged and filtrated before detection.The extract was separated in a short C_(18) reversed-phase column with gradient elution of acetonitrile and 0.1%formic acid as the mobile phase,at a flow rate of 0.3 mL/min and detected in multiple reaction monitoring(MRM),matrix matching external standard method were applied to samples analysis.The values obtained by repeating the measurement three times were relatively close,and the relative standard deviation(RSD)of each time was less than 5.2%,the value was stable and reliable,and the Z value was between 0.3 and 0.6.The result of this proficiency test is satisfactory,and the accuracy,precision and sensitivity of the method meet the requirements of pesticide residue detection.