Determination of hydroxyanthraquinoids in Rhubarb by cyclodextrin-modified micellar electrokinetic chromatography using a mixed micellar system of sodium dodecyl sulfate and sodium cholate

A cyclodextrin-modified micellar electrokinetic chromatographic (CD-MEKC) method was established to determine five hydroxyanthraquinoids in Rhubarb. The five components were successfully separated by using the mixed micellar system consisting of 20 mmol/l sodium dodecyl sulfate (SDS) and 20 mmol/l sodium cholate (SC) with 10 mmol/l beta-cyclodextrin in phosphate buffer (pH 10.4). The separation was optimized by adjusting buffer pH, concentrations of beta-cyclodextrin and SC and applied voltage. The proposed method was validated and applied to the determination of two commercial Rhubarb samples. The results obtained were satisfactory. (C) 2002 Published by Elsevier Science B.V.