直接进样杆大气压电离源-高分辨质谱法快速检测水果中的乙氧基喹啉残留

Rapid Quantification of Ethoxyquin Residue in Fruits by DIP-APCI-QTOF-MS

将直接进样杆大气压电离源(DIP-APCI)与串联四级杆飞行时间质谱(QTOFMS)联用,无需复杂样品前处理和色谱分离,建立了水果中乙氧基喹啉的快速检测方法。采用等体积进样和内标标准曲线法,提高了常压直接分析质谱的定量准确性,采用多反应监测(MRM)模式扫描,可有效降低基质干扰。该方法在0.1~10μg·mL^(-1)浓度范围内呈线性,相关系数R=0.9991,检测限为0.05mg·kg^(-1),在样品中分别添加0.05、2.0、5.0mg·kg^(-1)浓度水平的乙氧基喹啉,回收率为80%~106%,相对标准偏差为4.2%~8.7%。

We describe a method using direct inlet probe-atmospheric-pressure chemical ionization（DIP-APCI）coupled to high resolution QTOF-MS for the rapid quantitative analysis of ethoxyquin in fruits without cleanup and chromatographic separation.The accuracy of quantitative analysis was improved by using equal volume of injection and internal standard calibration curve,and the matrix interference was effectively reduced through the multiple reaction monitoring（MRM）mode.The detection limit for ethoxyquin was 0.052mg·kg^-1,and the linear range was 0.1-10μg·mL^-1 with a coefficient of 0.9991.The recoveries at three spkied levels were in the range of 80%-106% with relative standard deviations of 4.2%-8.7%.