J. Filipovicgrcic et al., CHITOSAN MICROSPHERES OF NIFEDIPINE AND NIFEDIPINE-CYCLODEXTRIN INCLUSION COMPLEXES, International journal of pharmaceutics, 135(1-2), 1996, pp. 183-190
Chitosan microspheres of nifedipine and nifedipine-cyclodextrin comple
xes were prepared by the glutaraldehyde cross-linking of chitosan. Mic
rospheres having different degrees of swelling were made by varying th
e cross-linking density. Drug incorporation efficiencies exceeding 70%
could be achieved for this drug. In vitro release rates were influenc
ed by the cross-linking density, particle size and initial drug loadin
g in the microspheres. While the solubility of nifedipine was enhanced
by inclusion into a cyclodextrin complex, the drug release from the c
omplex was significantly reduced. In addition the drug release mechani
sms were discussed.