Differentiation of Swertia Mussotii Franch from Artemisiae Capillaris Herba by capillary electrophoresis with electrochemical detection

A high-performance capillary electrophoresis (CE) with electrochemical detection (ED) method is developed for differentiation of Swertia Mussotii Franch from Artemisiae Capillaris Herba in this work. Swertia Mussotii Franch contains a great deal of swertiamarin and mangiferin that are not present in Artemisiae Capillaris Herba, whereas Artemisiae Capillaris Herba consists of abundant chlorogentic acid. Therefore, determining their swertiamarin, mangiferin and chlorogentic acid contents can differentiate these two crude herbs. Operated in a wall-jet configuration, a 300 μm diameter carbon-disk electrode was used as the working electrode, which exhibits good response at +1000 mV (versus SCE) for the three analytes. With a separation voltage of 14 kV, the three analytes were separated within 14 min in a 52 cm length capillary in 50 mmol/l borax buffer (pH 9.2). The system was demonstrated good stability and reproducibility with an R.S.D. of less than 5% for both migration time and peak current. This method was successfully used to analyze and identify the crude herbs with satisfactory assay results.