NIFEDIPINE AND FELODIPINE RELEASE FROM ETHYL CELLULOSE MICROSPHERES WITH UNIFORMSIZE AND SIZE DISTRIBUTION

摘要

The release profiles of nifedipine and felodipine, twowell-known drugs for hypertension, wereinvestigated using ethyl cellulose (EC) microspheresof different sizes as the delivery vehicles. The drugloadedmicrospheres with uniform size and sizedistribution were fabricated using the acousticexcitation method we previously reported. The drugswere homogeneously distributed in 25-μm-diametermicrospheres but more concentrated on the surfacein larger particles. The release profiles from 25-μmdiametermicrospheres exhibited zero-order releasewithout initial burst but low total percent release(7～10%) during the first 24 hours.