Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
Analyst. 2012 Nov 7;137(21):5135-43. doi: 10.1039/c2an36178g. Epub 2012 Sep 12.
A rapid and practical microwave-assisted one-step extraction-derivatization (MAED) method was developed for gas chromatography-mass spectrometry analysis of fatty acids profile in herbal medicine. Several critical experimental parameters for MAED, including reaction temperature, microwave power and the amount of derivatization reagent (methanol), were optimized with response surface methodology. The results showed that the chromatographic peak areas of total fatty acids and total unsaturated fatty acids content obtained with MAED were markedly higher than those obtained by the conventional Soxhlet or microwave extraction and then derivatization method. The investigation of kinetics and thermodynamics of the derivatization reaction revealed that microwave assistance could reduce activation energy and increase the Arrhenius pre-exponential factor. The MAED method simplified the sample preparation procedure, shortened the reaction time, but improved the extraction and derivatization efficiency of lipids and reduced ingredient losses, especially for the oxidization and isomerization of unsaturated fatty acids. The simplicity, speed and practicality of this method indicates great potential for high throughput analysis of fatty acids in natural medicinal samples.
一种快速实用的微波辅助一步提取衍生化（MAED）方法被开发用于草药中脂肪酸谱的气相色谱-质谱分析。通过响应面法对 MAED 的几个关键实验参数，包括反应温度、微波功率和衍生化试剂（甲醇）的量进行了优化。结果表明，与传统索氏提取或微波提取然后衍生化方法相比，MAED 得到的总脂肪酸和总不饱和脂肪酸含量的色谱峰面积明显更高。衍生化反应动力学和热力学的研究表明，微波辅助可以降低活化能并增加阿仑尼乌斯指数前因子。MAED 方法简化了样品制备程序，缩短了反应时间，但提高了脂质的提取和衍生化效率，减少了成分损失，特别是对不饱和脂肪酸的氧化和异构化。该方法简单、快速且实用，表明其在天然药用样品中脂肪酸高通量分析方面具有巨大潜力。
