چکیده (انگلیسی):

In this study an attempt was made to prepare mucoadhesive microcapsules of gliclazide using
various mucoadhesive polymers designed for oral controlled release. Gliclazide microcapsules were
prepared using sodium alginate and mucoadhesive polymer such as sodium carboxymethyl cellulose
(sodium CMC), carbopol 934P or hydroxy propylmethyl cellulose (HPMC) by orifice-ionic gelation
method. The microcapsules were evaluated for surface morphology and particle shape by scanning electron
microscope. Microcapsules were also evaluated for their microencapsulation efficiency, in vitro wash-off
mucoadhesion test, in vitro drug release and in vivo study. The microcapsules were discrete, spherical and
free flowing. The microencapsulation efficiency was in the range of 65–80% and microcapsules exhibited
good mucoadhesive property in the in vitro wash off test. The percentage of microcapsules adhering to
tissue at pH 7.4 after 6 h varied from 12–32%, whereas the percentage of microcapsules adhering to
tissue at pH 1.2 after 6 h varied from 35–68%. The drug release was also found to be slow and extended
for more than 16 h. In vivo testing of the mucoadhesive microcapsules in diabetic albino rats
demonstrated significant antidiabetic effect of gliclazide. The hypoglycemic effect obtained by
mucoadhesive microcapsules was for more than 16 h whereas gliclazide produced an antidiabetic effect
for only 10 h suggesting that mucoadhesive microcapsules are a valuable system for the long term
delivery of gliclazide.