Determination of berberine in Rhizoma coptidis and its preparations by non-aqueous capillary electrophoresis

A non-aqueous capillary electrophoretic method was established for the dete rmination of berberine in Rhizoma coptidis and its preparations. The effect s of organic solvent and the concentrations of sodium acetate were studied, which showed that berberine in extracts of traditional Chinese medicine ca n be separated successfully in a buffer solution of 75 mmol/L of sodium ace tate in methanol containing 1 mol/L of acetic acid. The simple and rapid me thod was linear in the range 25-200 mu g/mL of berberine and had a good rep roducibility, with the relative standard deviation below 2%. Non-aqueous ca pillary electrophoresis is a satisfactory system for the analysis of alkalo ids in traditional Chinese medicine. Copyright (C) 1999 John Wiley & Sons, Ltd.