Abstract

Shreyas K. S.*, Priyanka K. M. and Manjula Talluri

ABSTRACT

The present study is planned to prepare microsphere for sustained release of lamivudine. Microspheres are prepared using polymers such as Eudragit (RS100 & RL100) and magnesium stearate as the droplet stabilizer in order to get drops of uniform size by employing solvent evaporation method using an acetone and paraffin systems. Fourier Transform Infrared Spectroscopy (FTIR), X-ray powder diffractiometry and electron microscopy characterized the Microspheres after their preparation for their particle size determination, percentage yield and percentage drug entrapment efficacy. The in vitro release studies were performed in acidic buffer (pH1.2) and phosphate buffer (pH6.8). The prepared microsphere were white, free flowing and spherical in shape. The drug-loaded microsphere showed 70-90% of entrapment and release was extended up to 8 h. The infrared spectra showed stable character of lamivudine in drug-loaded microsphere and revealed the absence of drug : polymer interactions. X-ray diffraction pattern showed that there was decrease in crystallinity of the drug. Scanning electron microscopy studies revealed that microsphere were spherical in nature. The best fit of release kinetics was achieved with zero order. From the result of various parameters like yield value, % drug entrapment efficiency, microscopic evaluation, in vitro drug release studies and various kinetic model study, FS2 was selected as the best formulation among all prepared formulations.