PREPARATION AND EVALUATION OF ISONIAZID MICROCAPSULES

Document Type : Original Article

Authors

1 Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut, Egypt

2 Department of Pharmaceutical Medicinal Chemistry, Faculty of Pharmacy, Assiut University, Assiut, Egypt

Abstract

Spherical microcapsules of isoniazid (INH) using ethylcellulose and ethylene vinyl acetate copolymer (EVA) were prepared by a coacervation-phase separation method. The dissolution characteristics of isoniazid from microcapsules with different concentrations of EVA were almost independent of the content of EVA in phosphate buffer PH 7.4 but dissolution properties of microcapsules in 0.lN HcL and water were found to be affected by the content of EVA and there was a negative correlation between the release rate and the content of EVA in the microcapsules. Kinetic data revealed that the release mechanism from microcapsules followed diffusion controlled and zero order Kinetic.
The bioavailability of INH microcapsules was studied in rabbits. The mean maximum serum levels (Cmax) and time to maximum serum levels (tmax) were significantly different for INH microcapsules prepared using ethylcellulose only and those prepared with ethylcellulose and EVA copolymer, compared with INH powder. With regard to the area under the curve (AUC) value, there was no significant difference between INH powder and INH microcapsules.