高效毛细管电泳法测定板蓝根颗粒中的4种有机酸

Determination of four kinds of organic acids in Isatidis radix granules by capillary electrophoresis

目的采用高效毛细管电泳法测定板蓝根药材中水杨酸、丁香酸、苯甲酸和邻氨基苯甲酸的含量,并测定三家公司的两批板蓝根颗粒中的有机酸。方法采用重力进样,进样高度10 cm、时间30 s,正极进样,负极柱上202 nm检测;用含有15mmol·L-1β-环糊精的25 mmol·L-1硼砂缓冲盐溶液(pH9.1)-乙腈85∶15作为电泳缓冲液分离,操作电压11.5 kV;用甲醇溶解板蓝根颗粒,超声过滤,蒸干,用甲醇复溶定容后检测。结果在此条件下,4种有机酸在20 min内获得了理想的分离效果;不同厂家不同批号的板蓝根颗粒中有机酸的含量差异较大。结论所用方法简单、快速,可用于控制板蓝根颗粒中抗内毒素有机酸的质量。

OBJECTIVE To develop a high performance capillary electrophoresis method for the separation and determination of four kinds of organic acids in Isatidis radix granules, and measure organic acids in two batches of Isatidis radix granules from three companies. METHODS The sample was injected by gravity （30 s, 10 cm） from cathode and the detective wavelength was set at 202 nm. Sodium tetraborate（25 mmol·L^-1,pH9.1 ） and acetonitrile （85 ： 15） containing 15 mmol·L^-1 β - CD was used as running buffer with11.5 kV applied voltage. The granules were dissolved in methanol followed by ultrasound, filtration and drying, then were redissolved in 5 mL methanol for the detection. RESULTS Salicylic acid, syringic acid, benzoic acid and anthranilic acid were completely separa- ted and determined within 20 min. The granules made by different companies and Lots had different contents of organic acids. CONCLUSION The method is simple and rapid which could be used to determine four organic acids in Isatidis radix granules and monitor the quality of the granules.