Résumé
OBJECTIVE:To prepare domiphen bromide osmotic tablets,and to observe,analyze the mechanism of drug release.METHODS:Coating prescription was optimized by uniform design and the cumulative rates of drug release of different formulated preparations were measured,pharmaceutical features of domiphen bromide osmotic tablet and mechanism of drug release were studied.RESULTS:The dosage of PEG-400 and the coating membrane thickness all had an effect on drug release.The optimal coating technique was analyzed as 12%of PEG-400 and 10mg of coating.Spray speed,temperature and rotation speed did not affect releasing profiles.CONCLUSION:Improvement in formulation of coat of domiphen bromide osmotic tablet can result in drug release for 12h,whose mechanism includes diffusion and osmotic pump principle.
Résumé
OBJECTIVE:To prepare aspirin chitosan-sodium alginate microcapsules(ACSPM)and to investigate its optimal formula and releasing mechanism.METHODS:The formula of ACSPM was optimized by the orthogonal design with entrapment ratio as index,and then ACSPM was prepared,with its release rate determined as well.The releasing mechanism of aspirin from the microcapsules was established by equation fitting of releasing kinetic model.RESULTS:The prepared microcapsules were uniform in size and contents.The optimized formula was as follows:the concentration of sodium polymannuronate and chitosan were 3.0% and 1.0%,respectively,and the proportion of polymannuronate to aspirin was 1∶ 4.The in vitro drug release was in line with both Higuchi equation and Peppas equation.CONCLUSION:This preparation technology was simple and the drug releasing mechanism of the preparation was chiefly characterized by drug diffusion including bulk erosion non-Fickian process.