MICELLAR ELECTROKINETIC CAPILLARY CHROMATOGRAPHY SEPARATION AND DETERMINATION OF CHINESE TRADITIONAL MEDICINE──SEVERAL RHEUM SPECIES

A micellar electrokinetic capillary chromatographic(MECC) method for the separation and determination of emodin, aloe-emodin and rhein in several Rheum species was estab-lished. The buffer solution used in this method was a mixture of 0.025 mol·L^-1 3-cyclohexylamino-1-propane-sulfonic acid(containing 0.025 mol·L^-1 sodium dodecyl sulfate)-acetonitrile(100:10 ) at pH 10. 9 The linear calibration range was 2.5～17.5μg,ml^-1(r=0.9999) for aloe-emodin,0～50μg· ml^-1(r=0.9999) for emodin and 5.0～35μg·ml^-1(r=0.9996)for rhein. The recovery was 98.2%～101.8%for aloe-emodin, 99.9%～101.9%for emodin and 99.2%～101,2%for rhein. This method is simple, rapid and reproducible.