分散固相萃取-液相色谱-串联质谱法测定水果中19种酸性农药

摘要

建立了同时检测葡萄、苹果和桔子等水果中2,4-滴等19种酸性农药的分散固相萃取-液相色谱-串联质谱(HPLC-MS/MS)方法.葡萄、苹果和桔子样品经乙酸-乙腈(1:99,V/V)提取后,C18分散固相萃取净化,采用反相C18色谱柱分离.以0.1％甲酸和0.1％甲酸-乙腈溶液作为流动相进行梯度洗脱,采用多反应监测离子模式进行定性分析,基质标准曲线外标法进行定量分析,线性范围在0.01 ～ 0.2 mg/kg之间.在0.02,0.05和0.1 mg/kg添加水平下,19种酸性农药的回收率为70.3％ ～ 105.3％；相对标准偏差为0.37％ ～ 10.9％.本方法的定量限为0.005～ 0.02 mg/kg.%A method was developed for the determination of 19 acidic pesticides in fruit by dispersive solid phase extraction and liquid chromatography-tandem mass spectrometry ( LC-MS/MS). The 19 analytes were extracted from the fruit samples by acetic acid-acetonitrile (1 :99, V/V) , and purified by dispersion solid phase extraction using C18 sorbent, and then analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The 19 analytes were then separated on a reversed phase column using a gradient elution program of aqueous solution containing 0.1% formic acid aqueous solution and 0. 1% formic acid acetonitrile solution. Qualitative analysis was performed using multiple-reaction monitoring ( MRM). Matrix-matched calibrations were respectively used to quantify the residue concentrations. The recoveries were in the range of 70.3% -105. 3%, and the relative standard deviation ( RSDs) were 0. 4-10. 9% at 0. 02 mg/kg, 0.05 mg/kg and 0. 1 mg/kg three spiked levels for all analytes. The limits of quantification (LOQ) for all analytes were between 0. 005 mg/kg and 0. 02 mg/kg.