基于两步衍生化-LC-MS法的体内游离脂肪酸定性分析研究

Qualitative study of free fatty acids based on two-step derivatization-LC-MS method

关键词:  游离脂肪酸 衍生化 高效液相色谱-质谱法

Key words:  free fatty acids derivatization? HPLC-MS

摘要:

目的:建立两步衍生化-高效液相色谱质谱联用方法,对生物样本中的游离脂肪酸进行定性分析,重点区分双键位置异构体。方法:采用间氯过氧苯甲酸和N,N-二乙基乙二胺对6种具有不同饱和度的代表性游离脂肪酸进行两步衍生化,高效液相色谱串联三重四极杆质谱检测。结果:经标准品验证,证明采用质谱裂解数据回溯游离脂肪酸结构的分析思路可行、可靠；从比格犬血浆中共鉴定出游离脂肪酸38种,其中单不饱和的13种,多不饱和的17种,饱和的8种；可区分双键位置异构体10种,并准确定位低丰度的二十二碳六稀酸双键位置。结论:建立的两步衍生化-高效液相色谱质谱联用方法为体内游离脂肪酸的定性分析,特别是区分双键位置异构方面提供了新的思路,也为相关代谢组学、脂质组学研究提供了方法学支撑。

Abstract:

ABSTRACT: OBJECTIVE: To establish a two-step derivatization and high performance liquid chromatography-mass spectrometry method , and to qualitatively study the free fatty acids in biological samples, with a focus on distinguishing double bond isomers. METHOD: Six representative free fatty acids with different saturation were subjected to two-step derivatization using m-chloroperoxybenzoic acid and N, N-diethylethylenediamine. Liquid chromatography-mass spectrometry was used for analysis and detection. RESULTS: Verified by 6 free fatty acid standards, the analysis approach of mass spectrometry fragmentation data backtracking structure is feasible and reliable. A total of 38 kinds of free fatty acids were identified from Beagle plasma, including 13 monounsaturated, 17 polyunsaturated and 8 saturated. It can distinguish 10 kinds of double bond isomers and accurately analyze the double bond positions of low abundance docosahexadilute acids. CONCLUSION: The established two-step derivatization and high performance liquid chromatography mass spectrometry method provides a new idea for the qualitative analysis of free fatty acids in vivo, especially for the differentiation of double bond isomerism, and also provides methodological support for related metabolomics and lipidomics studies.