DETERMINATION OF SIX EFFECTIVE COMPONENTS IN RHEUM BY CYCLODEXTRIN MODIFIED MICELLAR ELECTROKINETIC CHROMATOGRAPHY

AIMTo determine six effective components (aloe-emodin, rhein, emodin, rhaponticin, physcion and chrysophanol) in RHEUM. METHODSUsing buffer solution containing 20 mmol·L^-1 borax, 20 mmol·L^-1 sodium deoxycholate (SDC), 20 mmol·L^-1 sodium taurocholate (STC), 15 mmol·L^-1 β-cyclodextrin (β-CD) and O-phthalic acid as the internal standard, the six components were determined by cyclodextrin modified micellar electrokinetic chromatography. RESULTSIn less than 25 min, aloe-emodin, rhein, emodin, rhaponticin, physcion and chrysophanol were separated. The separation conditions were optimized by adjusting buffer pH, concentrations of SDC, STC and β-CD. The linearity ranges of aloe-emodin, rhein, emodin, rhaponticin, physcion and chrysophanol were 4～34, 5～40, 4～60, 5～80, 6～90 and 5～85 μg·mL^-1 respectively. Relative standard deviation (RSD) of the method was less than 2.2%. The recoveries of aloe-emodin, rhein, emodin, rhaponticin, physcion and chrysophanol were 100.0%, 98.3%, 100.4%, 94.6%. 95.2% and 93.8% respectively. Raw RHEUM, Mongolian RHEUM and Rheum tanguticum samples were analyzed. CONCLUSIONThis method can be an effective one for identification of Rhubarb.