ABSTRACT
OBJECTIVE:To establish a method for the simultaneous content determination 5 anthraquinones of rhei radix-copti-dis rhizoma,and optimize its best mass ratio. METHODS:HPLC was performed on the column of Zorbax SB-C18 (250 mm × 4.6 mm,5 μm)with mobile phase of acetonitrile-0.05 mol/L potassium dihydrogen phosphate(48:52, V/V,adding sodium dodecyl sulfate 0.4 g per 100 mL,pH value was adjusted to 4.0);detection wavelength was 254 nm;flow rate was 1 mL/min;column tem-perature was 25℃;and injection volume was 10μL. When mass ratio of rhei radix-coptidis rhizoma was 1:1,1:2,2:1,2:3,3:2,the contents of aloe emodin,rhein,emodin,chrysophanol and emodin ether were investigated. RESULTS:The aloe emodin, rhein, emodin, chrysophanol and emodin ether showed good linear relationship with peak area in the range of 0.652-3.081, 0.704-3.422,1.280-6.197,0.633-0.324,1.326-5.954 μg(r≥0.9997);RSDs of precision,stability,reproducibility tests were low-er than 2.0%(n=6);and average recovery was 98.92%-100.37%(RSD≤2.26%,n=6). When mass ratio was 2:1,the total contents of 5 ingredients were the highest. CONCLUSIONS:The method has good precision,stability,reproducibility,and can be used for the quality verification of rhei radix-coptidis rhizoma under different compatibilities. The best mass ratio of rhei radix-copti-dis rhizoma is 2:1.