[关键词]
[摘要]
比较了固相萃取(SPE)、固相微萃取(SPME)、双水相萃取(LLE)作为预处理方法萃取白酒中氨基甲酸乙酯的效率,并联合气相色谱-质谱(GC-MS)对白酒中氨基甲酸乙酯进行测定,通过方法学验证评价各方法的准确度和精密性。结果显示:对于三种香型的白酒来说,SPE-GC/MS法检测精密性最好(1.77%~2.96%)、准确度最高(回收率89.73%~103.51%),检测限最低(1.12 μg/L);SPME-GC/MS方法检测清香型白酒的效果优于LLE-GC/MS;LLE-GC/MS方法检测浓香型、酱香型白酒效果优于SPME-GC/MS方法。综合考虑各因素,LLE-GC/MS因其准确度较高、精密度较好、简便快速、成本低经济、有机溶剂用量少环保、易于掌握,满足一般性定量检测要求,适合用于我国白酒中氨基甲酸乙酯含量的常规分析检测。SPE-GC/MS准确度高、精密度良好,但由于操作过程繁琐、成本高、有机溶剂用量多不环保,适用于精密分析。
[Key word]
[Abstract]
The efficiency of solid phase extraction (SPE), solid phase microextraction (SPME), liquid/liquid extraction (LLE) were compared with regard to extraction of ethyl carbamate (EC) from liquor and the accuracy and precision of each method were validated. The ethyl carbamate content in liquor was estimated by gas chromatography-mass spectrometry (GC-MS). The results showed that for the three kinds of liquor with different flavors analyzed in this study, SPE-GC/MS exhibited the highest precision (1.77% to 2.96%), the highest accuracy (recovery=89.73% to 103.51%), and the lowest limit of detection (1.12 μg/L). SPME-GC/MS showed higher efficiency in determination of ethyl carbamate content in fen-flavor liquor compared with LLE-GC/MS, which on the other hand, showed higher efficiency in determination of ethyl carbamate content in luzhou-flavor liquor and maotai--flavor liquor compared with SPME-GC/MS. Based on these findings, the LLE-GC/MS method showed high precision, high accuracy, and low cost. LLE-GC/MS is also a simple and rapid test, is environmentally friendly (small amount of organic solvent required), meets the requirements for general quantitative analysis, and staff can be trained easily. SPE-GC/MS on the other hand, shows high recovery and reproducibility, but the method is complicated, not environmentally friendly (a large amount of organic solvent required), and expensive. Therefore, LLE-GC/MS was found suitable for routine, precise determination of ethyl carbamate in Chinese liquor.
[中图分类号]
[基金项目]
国家863科技计划项目(2013AA102108);天津市科技支撑计划项目(15ZCZDNC00110)