液相微萃取 - 高效液相色谱法测定制首乌中蒽醌类化合物

 目的 中空纤维液相微萃取结合高效液相色谱法同时对制首乌中蒽醌类化合物作定量分析。 方法 利用自制的液相微萃取装置，以聚偏氟乙烯纤维（ MOF503 ）为溶剂载体，正辛醇为萃取溶剂，供相中 HCl 浓度为 2 mmol·L^-1 ，供相中甲醇比例为 50% ，搅拌速度为 1 800 r·min^-1 ，萃取时间为 60 min 。萃取结束，萃取液经 80 ℃ 水浴蒸干后用 60 μL 甲醇溶解，在 434 nm 处进行 HPLC 分析 。 结果 在优化的液相微萃取条件下， 芦荟大黄素 、大黄酚、大黄酸、大黄素甲醚和大黄素检测限分别为： 0.30 ， 0.25 ， 0.25 ， 0.35 和 0.30 μg·L^-1 ，精密度在 8.1% ～ 14.1% 之间，在制首乌中的回收率在 75.4% ～ 111.5% 之间。 5 种化合物液相微萃取富集倍数分别为 21 ， 21 ， 36 ， 44 ， 47 倍。测定了制首乌中大黄素、大黄素甲醚和痕量大黄酸、大黄酚的含量 。 结论 液相微萃取是一种简单、快速、选择性高、富集倍数高、有机溶剂消耗少的样品前处理技术，可用于同时分析制首乌药材中蒽醌类化合物 。

Determination of Anthraquinones in Radix Polygoni Multiflori Praeparata by Liquid-phase Microextarction- High Performance Liquid Chromatography

OBJECTIVE To quantitatively analyze anthraquinones in Radix Polygoni Multiflori Praeparata by liquid-phase microextraction (LPME) coupled with high performance liquid chromatography. METHODS With a self-made LPME system, the optimal extraction conditions were as follows: polyvinylidene difluoride hollow fiber as solvent carrier, 1-octanol as extraction solvent, HCl concentration in the donor was 2 mmol·L-1, methanol content in the donor was 50%, the stirring rate was 1 800 r·min-1 and the extraction time was 60 min. After microextraction, the extract was dried in 80 ℃ water bath, dissolved with 60 μL methanol and then analyzed by HPLC at 434 nm. RESULTS Under the optimal conditions, detection limits of aloe-emodin, crysophanol rhein, physcion and emodin were 0.30, 0.25, 0.25, 0.30 and 0.35 μg·L-1, respectively. The average relative standard deviation (precision) ranged from 8.1% to 14.1%. The relative recoveries in Radix Polygoni Multiflori Praeparata ranged from 75.4% to 111.5%. The LPME enrichment factors of the five analytes were 21, 21, 36, 44 and 47 respectively. Emodin, physcion, trace rhein and crysophanol in Radix Polygoni Multiflori Praeparata were determined. CONCLUSION Liquid-phase microextraction is a pre-processing technique which is simple, quick, with high selectivity, high enrichment factor and little organic solvent consumption. It could be applied to simultaneous analysis of anthraquinones in Radix Polygoni Multiflori Praeparata.