G/CMS同时检测人尿中N,N-二甲基乙酰胺及其代谢产物N-甲基乙酰胺

Determination of N,N-Dimethylacetamide and it′s metabolite N-Methylacetamide in human urine by GC/MS

目的:探讨利用气相色谱-质谱(GC/MS)建立一种准确可靠的尿样中的N,N-二甲基乙酰胺(DMAC)及其代谢产物N-甲基乙酰胺(NMAC)的测定方法。方法:尿样经乙酸乙酯萃取、浓缩后,用GC/MS全扫描模式(scan)进行定性分析,确定组分出峰时间和特征质量离子,DMAC选择15、44、87m/z,NMAC选择30、43、73m/z,进行选择离子扫描(SIM),作定量分析。结果:DMAC和NMAC的线性范围分别为0.1 mg/L^10.0 mg/L和0.5 mg/L^10.0 mg/L;相关系数分别为0.9993和0.9991;最低检出限分别为0.02 mg/L和0.10 mg/L;相对标准偏差分别为3.26%和7.22%;样品加标回收率分别为91%~99%和88%~102%。结论:方法准确性好、灵敏度高、干扰少,是检测尿样中DMAC和NMAC的较好方法。

Objective：To develop an accurate,reliable method to determine N,N-Dimethylacetamide（DMAC） and it′s metabolite N-Methylacetamide（NMAC） in human urine by GC/MS.Methods： The urine was extracted and concentrated with ethyl acetate firstly,and then qualitatively analyzed by GC/MS full scan mode to determine the retention time and characteristic mass ions,and quantitatively analyzed in selective ion monitor with ions at m/z 15,44,87 for DMAC and m/z 30,43,73 for NMAC.Results： The calibration curves of DMAC and NMAC were linearly in the range of 0.1 to 10.0 mg/L（correlation coefficient was 0.9993） and 0.5 to 10.0 mg/L（correlation coefficient was 0.9991）,respectively.The detection limits,relative standard deviations,recovery ranges for DMAC and NMAC were 0.02 mg/L and 0.10 mg/L,3.26% and 7.22%,91% to 99% and 88% to 102%,respectively.Conclusion： This method had high accuracy,high sensitivity and low interference.It could be applied to determine DMAC and NMAC in human urine.