Formulation and In-vitro Evaluation of Zidovudine Loaded Ethyl Cellulose Microcapsules

Microencapsulation is a well-known method that is used to modify and retard drug release. In this study, the preparation of Zidovudine loaded microcapsule was accomplished in order to assess the suitability of them for production of oral/vaginal sustained release multiparticulate dosage form of Zidovudine. Microcapsules were prepared using the solvent evaporation method. The effect of formulation variable like polymer: drug ratio was investigated on shape and surface characteristics of microcapsules (by scanning electron microscopy), percentage yield and drug entrapment efficiency, mean particle size and drug release profiles (dissolution test). Microscopic examination of microcapsules revealed that microcapsules were well-shaped and nearly spherical. FTIR studies revealed that no interactions were found between the drug and the polymer. The particle size of all the formulations were found to be satisfactory and within the range of 60.06 to 85.28 μm The percentage yield of all the formulation was found to be satisfactory except MC5. The percentage yield varied from 60.16 to 92.52% suggesting that the processing parameters did not affect the yield from the solvent evaporation method. Dissolution studies were carried out and zero order, first order and higuchi kinetics were implemented to predict the release kinetics. To justify the result Korsmeyer and Peppas model was applied and data shows that all formulations released the drug by diffusion following Fickian (n<0.5) transport mechanism.