Quality evaluation of Liuwei Dihuang Pill / 中成药

ABSTRACT

AIM: To compare the quality of Liuwei Dihuang Pill among the pharmaceutical companies by determining the content and the dissolution of paeonol of Liuwei Dihuang Pill. METHODS: A method of determining paeonol and the dissolution from Liuwei Dihuang Pill was establishod. HPLC was used with methanol-water (70 ∶30) as a mobile phase and detection wavelength was at 274 nm. The flow rate was 1.0 mLmin, injection volume was 20 ?L. The percentage of dissolution was determined in the 30% methanol- 0.1 mol1 HCL solution. RESULTS: A good linearity was over the weight range of 1.4 ?g-140 ?g, the average recovery was 97.38% , the RSD for reproducibility was 1.44% (n=6). The parameter of Tianjin’s production was T_ 50 = 156.77 , T_d= 256.55 ,M= 0.734 and the parameter of Beijing’s production was T_ 50 = 110.66 , T_d= 197.19 , M= 0.583 . CONCLUSION: The method is simple, and can be used to determine the content and the percentage of dissolution of paeonol in Liuwei Dihuang Pill. The experiment indicates that the percentage of dissolution has no obvious distinction in products from different manufactures; but has obvious distinction in the batches of same manufacture.