超临界流体萃取-胶束电动毛细管色谱法测定银杏叶粗提物中槲皮素和山奈素的含量

Determination of quercetin and kaempferol in Ginkgo biloba extract by supercritical fluid extraction and micellar electrokinetic capillary chromato-graphy

目的 :以超临界流体萃取 ( SFE)银杏叶粗提物中槲皮素和山奈素 ,以胶束电动毛细管色谱法 ( MECC)测定这两种成分的含量。 方法 :采用正交设计法考察 SFE提取工艺 ,SFE条件 :压力 42 m Pa;温度 6 0℃ ;静态萃取时间 4m in;动态萃取体积 4m l;改性剂 0 .2 ml乙醇。 MECC条件 :空心熔融石英毛细管柱 ( 5 5 cm× 75μm ) ;缓冲液为磷酸二氢钠 -硼砂 =2 5 - 6 .2 5mm ol/L ( p H 8.5 ) ;SDS 35 mmol/L ;检测波长 2 5 4nm。结果 :SFE时改性剂对萃取效率的影响最大 ;MECC以肉桂酸为内标 ,在 2 1.2～ 10 6 .0μg/ml和 2 0 .0～ 10 0 .0μg/ml范围内 ,槲皮素和山奈素均呈良好的线性关系和重现性。 40 ,6 0和 80μl槲皮素的加样回收率分别为 93.87% ,94.0 2 %和 94.10 % ;40 ,6 0和 80μl山奈素的加样回收率分别为 94.5 0 % ,94.17%和 94.2 5 %。结论 :SFE与 MECC法联用 ,简便快速 ,可用于银杏叶粗提物中的黄酮类成分的分离分析。

Objective: To establish a method for the determination of quercetin and kaempferol in Ginkgo biloba extract. Methods: A simple, rapid and reproducible supercritical fluid extract (SFE) and capillary electrophoretic method were developed for it. SFE was selected by orthogonal design method. SFE conditions: temperature 60 ℃, pressure 42 mPa, static extraction 4 min, dynamic extraction volume 4 ml and 0.2 ml ethanol as modifier. MECC conditions were 55 cm×75 μm fused silica capillary column. The running buffer contained 25 mmol/L sodium dihydrophosphate, 6.25 mmol/L sodium borate (pH= 8.5) and 35 mmol/L sodium dodecyl sulfate(SDS). The detection wave length was at 254 nm. Results: The influence of modifier on extraction rate in SFE was the most. The linear range for quercetin and kaempferol was 21.2 106.0, 20.0 100.0 μg/ml, respectively, when cinnamic acid was in an internal standard. The recovery of quercetin for 40, 60 and 80 μl was 93.87%, 94.02% and 94.10%, respectively. The recovery of kaempferol for 40, 60 and 80 μl was 94.50%, 94.17% and 94.25%, respectively. Conclusion: SFE MECC is convenient and accurate method, and can be used as a measure of quality control for Ginkgo biloba extract. [