饱和盐辅助-分散液液微萃取-气相色谱-串联质谱法快速筛查啤酒中氨基甲酸乙酯与9种挥发性亚硝胺

Rapid determination of ethyl carbamate and 9 kinds of volatile nitrosamines in beer by gas chromatography-tandem mass spectrometry with saturation salt assisted-dispersible liquid-liquid microextraction

目的建立饱和盐辅助-分散液液微萃取(saturation salt assisted-dispersible liquid-liquid microextraction,SSA-DLLME)快速样品前处理,气相色谱-串联质谱法(gas chromatography-tandem mass spectrometry,GC-MS/MS)检测啤酒中氨基甲酸乙酯和9种挥发性亚硝胺包括N-亚硝基二甲胺、N-亚硝基二正丙胺、N-亚硝基二乙胺、N-亚硝基哌啶、N-亚硝基吡咯烷、N-亚硝基吗啉、N-亚硝基甲乙胺、N-亚硝基二丁胺和N-亚硝基二苯胺的检测方法。方法样品经甲醇提取,加入稳定同位素标记的目标物定量,在饱和碳酸钠辅助萃取下,猛力注入二氯甲烷进行SSA-DLLME,离心,取下层有机相进样,多反应监测(multiple reaction monitoring,MRM)模式进行GC-MS/MS检测,内标法定量。结果该方法在考察的浓度范围内线性良好(r^(2)>0.9970),方法检出限(limits of detection,LODs)为0.10~0.34μg/L,定量限(limits of quantitation,LOQs)为0.34~1.15μg/L;3水平(1、5、10μg/L)加标回收率为81.98%~123.50%,相对标准偏差(relative standard deviations,RSDs)为0.57%~13.04%(n=8)。结论该方法极为简便、快捷,检出限低且准确度好,可满足啤酒中氨基甲酸乙酯和9种挥发性亚硝胺快速筛查检测的需要。

Objective To establish a fast sample pretreatment method of saturation salt assisted-dispersible liquid-liquid microextraction(SSA-DLLME),and determine of ethyl carbamate and 9 kinds of volatile nitrosamines in beer by gas chromatography-tandem mass spectrometry(GC-MS/MS),including N-nitrosodimethylamine,N-nitrosodinopropylamine,N-nitrosodiethylamine,N-nitrosopiperidine,N-nitrosopyrrolidine,N-nitrosomorpholin,N-nitrosodiethylamine,N-nitrosodibutylamine and N-nitrosodiamine.Methods The samples were extracted with methanol,and the target substances labeled with stable isotopes were added for quantification,under the assistance of extraction with saturated sodium carbonate,dichloromethane was forcibly injected for SSA-DLLME,which was centrifuged,and the upper organic phase was injected,and multiple reaction monitoring(MRM)mode was used for GC-MS/MS detection,and internal standard method was used for quantitative determination.Results The linearities were good(r 2>0.9970)within the concentration range investigated,the limits of detection(LODs)were 0.10‒0.34μg/L,and the limits of quantitation(LOQs)were 0.34‒1.15μg/L;the recoveries at the 3 levels(1,5,and 10μg/L)were 81.98%‒123.50%and the relative standard deviations(RSDs)were 0.57%‒13.04%(n=8).Conclusion This method is simple,rapid,with low detection limit and good accuracy,and can meet the needs of rapid screening and detection of ethyl carbamate and 9 kinds of volatile nitrosamines in beer.