Abstract

Indomethacin microcapsules with a coat consisting of alginate and a mucoadhesive polymer such as sodium carboxymethylcellulose, methyl cellulose, carbopol and hydroxypropylmethylcellulose were prepared by an emulsification-ionic gelation process and were investigated with a view to develop mucoadhesive microcapsules. The resulting microcapsules were discrete, large, spherical and free flowing. Microencapsulation efficiency was 41-70% and relatively high with alginate-sodium carboxymethylcellulose. The microcapsules exhibited good mucoadhesive property in the in vitro wash-off test. lndomethacin release from these mucoadhesive microcapsules was slow and extended over longer periods of time and de pended on the composition of coat and size of the microcapsules. Drug release was diffusion controlled and followed first order kinetics. Alginate-methyl celiulose and alginate-sodium carboxymethylcellulose microcapsules were found suitable for oral controlled release. Release fromsome microcapsules fulfilled the official (USP 23) drug release test-2 requirement of indomethacin extended release capsules.