Determination of Chlorogenic Acid, Glycyrrhizin and Glycyrrhetinic Acid in Yinqiaojiedupian by High Performance Capillary Electrophoresis
高效毛细管电泳法测定银翘解毒片中的氯原酸、甘草酸和甘草次酸

A simple, rapid and reproducible capillary electrophoretic method was developed for the determination of chlorogenic acid, glycyrrhizin and glycyrrhetinic acid in Yinqiaojiedupian. The buffer solution used in this method was a mixture of 20 mmol/L NaH2PO4 and 5 mmol/L Na2B4O7(pH 7.0). The other conditions were as follows: applied voltage, 20 kV (positive to negative polarity); L = 60 cm; Leff = 55 cm; i.d. = 75 microns; lambda = 254 nm; temperature, 25 degrees C; injection time, 5 s hydrostatic. The linear calibration range was 1.568-100.4 mg/L for glycyrrhetinic acid, 8.000-128.0 mg/L for glycyrrhizin and 8.080-129.3 mg/L for chlorogenic acid, and recoveries were 98.0%-103% for glycyrrhetinic acid, 97.3%-102% for glycyrrhizin and 97.3%-100% for chlorogenic acid. The relative standard deviations (n = 3) were 0.2%-1.3% (intra-day) and 1.9%-3.0% (inter-day) for glycyrrhetinic acid, 0.5%-1.2%(intra-day) and 1.9%-2.1%(inter-day) for glycyrrhizin and 0.7%-1.3%(intra-day) and 1.6%-2.1%(inter-day) for chlorogenic acid. The contents of these three acids in Yinqiaojiedupian were successfully determined within 10 min.