建立了一种离子液体(1-乙基-3-甲基咪唑四氟硼酸盐,1E-3MI-TFB)修饰毛细管胶束电动色谱法分离测定异槲皮甙、绿原酸和槲皮素的方法。研究了缓冲溶液的酸度和浓度、牛磺胆酸纳的浓度以及1E-3MI-TFB对分离的影响。分离的最佳条件为:25mmol/L硼砂.磷酸二氢钾(pH9.0)40mmol/L牛磺胆酸钠-1‰(V/V)1E,3MI-TFB,电压16kV。在优化条件下,3种分析物在11min内可以得到良好的分离。异槲皮甙、绿原酸和槲皮素的峰面积和浓度分别在0.02—0.40、0.02—0.20和0.08—0.60g/L浓度范围内呈良好的线性;线性相关系数分别为0.9998、0.9988和0.9991;3种物质基于峰面积的相对标准偏差分别为:2.48%,2.56%和3.03%;基于迁移时间的相对标准偏差分别为1.12%、1.46%和1.59%;检出限(S/N=3)分别为:异槲皮甙,0.0050g/L;绿原酸,0.0045g/L;槲皮素,0.0040g/L。将此方法应用于分离测定欧亚旋覆花中的异槲皮甙、绿原酸和槲皮素,取得良好结果。
An ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate, 1E-3MI-TFB ) modified micellar electrokinetic capillary chromatographic (MEKC) method was developed to separate and determine isoquercitrin, chlorogenic acid and quercetin. The effects of buffer pH and concentration, sodium taurocholate (STC) concentration and ionic liquid on separation were investigated. The optimum electrophoretic conditions were as follows : 25 mmol/L borax-KH2PO4 ( pH 9.0) - 40 mmol/L STC-1‰ 1E-3 MI-TFB (V/V) as the running buffer, applied voltage of 16 kV. Under the optimized conditions, the three analytes were well separated less than 11 rain. A good linearity between the peak area and the concentration was observed in the range of 0.02 - 0.40 g/L, 0.02 - 0.20 g/L and 0.08 - 0.60 g/L with correlation coefficients of 0. 9998, 0.9988 and 0. 9991 for isoquercitrin, chlorogenic acid and quercetin, respectively. The relative standard deviation in peak area and migration time was 2.5% and 1.1% for isoquercitrin, 2.6% and 1.5% for chlorogenic acid, 3.0% and 1.6% for quercetin. The detection limits (S/N = 3 ) were 0. 0050 g/L for isoquercitrin, 0. 0045 g/L for chlorogenic acid and 0. 0040 g/L for quercetin. The method was successfully applied to separate and determine isoquercitrin, chlorogenic acid and quercetin in Inula britamica L.