Objective:To compare the drug release of nifedipine sustained-release tablets from four manufacturers to evaluate the intrinsic quality. Methods:The drug release rate was determined by UV respectively with pH 1. 2 HCl solution, pH 4. 0 sodium ace-tate buffer, pH 6. 8 phosphate buffer and water as the dissolution medium. The dissolution curves were compared by f2 factor. Results:The drug release rate of nifedipine sustained-release tablets from the four manufacturers all met quality standard of our country, al-though the dissolution curves in the different dissolution medium was various. Conclusion:There are differences in intrinsic quality a-mong the nifedipine sustained-release tablets from the four manufacturers. The dissolution examination standard should be improved fur-ther.

OBJECTIVE:To establish a method for the content determination of cabozantinib in its raw material. METHODS:RP-HPLC method was adopted. The determination was performed on Inertsil ODS-SP C18 column with mobile phase consisted of acetonitrile-0.02 mol/L ammonium acetate buffer (pH 5.2,52:48,V/V) at the flow rate of 1.0 mL/min. Detection wavelength was set at 241 nm,the column temperature was 38 ℃,and sample size was 20 μL. RESULTS:The linear range of cabozantinib were 9.88-49.40 μg/mL(r=0.9999). The limit of quantitation was 11.46 ng,and the limit of detection was 3.36 ng. The RSDs of preci-sion,stability,repeatability tests were all lower than 2.0%;recoveries were 98.5%-101.7%(RSD=1.2%,n=9). CONCLU-SIONS:The method is simple,accurate and suitable for the content determination of cabozantinib in its raw material.