RESUMEN
Objective: To establish a dissolution determing method for the two primary ingredients atenolol and nifedipine in YakepingⅡcapsules. Methods:A small glass method was adopted with the rotation rate of 50 r·min-1 . According to the dissolution conditions in Japan “quality of medical drugs information set” with appropriate adjustments in accordance with the actual situation of the samples, different YakepingⅡ capsules were determined by HPLC respectively in pH 1. 2 artificial gastric solution ( containing 0. 5% sodium dodecyl sulfate), pH 4. 0 acetate buffer(containing 0. 5% sodium dodecyl sulfate), pH 6. 8 phosphate buffer(contai-ning 0. 25% sodium dodecyl sulfate) and water(containing 0. 25% sodium dodecyl sulfate). Results:The assay displayed a good lin-earity over the concentration range of 10-30 μg·ml-1 for atenolol and nifedipine(r=0. 999 6 and r=0. 999 8), and the recovery of the two components in the different medium was 99. 64%(RSD=0. 73%), 99. 55%(RSD=0. 65%), 99. 53%(RSD=0. 47%)and 99.54% (RSD=0.51%), 99.52%(RSD=0.67%), 99.52%(RSD=0.72%), 99.51%(RSD=0.63%)and 99.61%(RSD=0. 59%)(n=9). The dissolution of different batches of YakepingⅡcapsules in the four media showed the similar behavior. Conclu-sion:The method is simple, accurate and reproducible in the dissolution determination of atenolol and nifedipine in YakepingⅡ cap-sules.