MEKC-DAD fingerprint of Radix et Rhizoma Rhei.

Objective:To establish the analytical method for the fingerprint of Radix et Rhizoma Rhei by MEKC-DAD and compare the fingerprints of Radix et Rhizoma Rhei and its processed products.Method:Based on the mode of micellar electrokinetic chromatography,25 mmol·L-1 borax-25 mmol·L-1 SDS-10% acetonitrile was selected for the running buffer(pH 9.2).The separation voltage was 12 kV and the detection wavelength was set at 254 nm.Rhein was used as a reference standard,the chromatographic fingerprint was determined via the data analyzed by fuzzy cluster and fingerprint similarity evaluation software to compare the similarity of samples.Result: MEKC-DAD fingerprints with 11 common peaks of 10 batches of Radix et Rhizoma Rhei from the place of the genuine were established preliminarily.It was discovered that a small number of samples differed from others.Regarding to the fingerprints of Radix et Rhizoma Rhei and its processed products,there were obvious differences in the relative areas of common peaks.Conclusion: The method is reliable,accurate and can be used for quality control of Radix et Rhizoma Rhei.