液相色谱串联质谱法测定蔬菜中36种农药残留

Determination of 36 Pesticide Residues in Vegetables by Liquid Chromatography-Tandem Mass Spectrometry

为有效监测蔬菜中的农药残留,本文采用QuEChERS前处理结合液相色谱-三重四极杆串联质谱技术,以南瓜为实验样品建立一种同时检测蔬菜中多种农药残留的方法。采用电喷雾离子源正负离子多反应监测模式进行分析,空白基质液匹配混合标准曲线,外标法定量;以1μL的进样量,用2 mmol·L^(-1)甲酸铵(含0.01%甲酸水溶液)和2 mmol·L^(-1)甲酸铵(含0.01%甲酸甲醇)为流动相进行梯度洗脱。结果表明,36种农药在1~400 ng·mL^(-1)有良好的线性关系,相关系数r>0.998,检出限为0.1~1.8μg·kg^(-1),定量限为0.2~6.0μg·kg^(-1),加标回收率为78.3%~113.0%,相对标准偏差为0.7%~7.4%。该方法操作简单快速,灵敏度高,可为蔬菜中农药的安全监管提供技术支持。

To effectively monitor pesticide residues in vegetables,this article adopts the QuEChERS pretreatment method combined with liquid chromatography-triple quadrupole tandem mass spectrometry technology was used in the experiment to establish a method for simultaneous detection of multiple pesticide residues in vegetables with pumpkin as the test sample.The experiments were carried out in multiple reaction monitoring mode with electrospray ion source.The blank matrix solution was matched with mixed standard curve and quantized by external standard method.Gradient elution was performed with 2 mmol·L^(-1)ammonium formate(containing 0.01%formic acid aqueous solution)and 2 mmol·L^(-1)ammonium formate(containing 0.01%formic acid methanol)as mobile phase at the sample size of 1μL.The results showed that the 36 pesticides had a good linear relationship in the range of 1~400 ng·mL^(-1),the correlation coefficient r>0.998,the detection limits were 0.1~1.8μg·kg^(-1),the limits of quantitation were 0.2~6.0μg·kg^(-1),and the standard recoveries were 78.3%~113.0%.The relative standard deviation ranges from 0.7%to 7.4%.The method is simple,rapid and sensitive,it can provide technical support for the safety supervision of pesticides in vegetables.