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 x L(-1) borax -25 mmol x 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.