Preparation and characterization of lamivudine microcapsules using various cellulose polymers

Purpose: The objective of the present study was to prepare and evaluate microcapsules for the controlled release of lamivudine using various cellulose polymers Methods: The microcapsules were prepared by the solvent evaporation method. The prepared microcapsules were characterized for the percent drug content, entrapment efficiency, FTIR, DSC, scanning electron microscopy (SEM) and in vitro dissolution studies. Accelerated stability studies were also carried out. Results: The microcapsules were spherical and free flowing. The entrapment efficiency was 76-86%. The release of drug from the microcapsules extended up to 8 to 12 hours. FTIR and DSC thermograms showed the stable character of lamivudine in the microcapsules. SEM revealed that the microcapsules were porous in nature. The release kinetics study revealed that the prepared microcapsules were best fitted to the zero order for F-2, F-4 and F-5 formulations and Higuchi model, for F-1 and F-3 microcepsules Conclusion: The release kinetics data and characteristion studies indicate that drug release from microcapsules was diffusion – controlled and that the micrapsules were stable. Keywords: Lamivudine, cellulose polymers, microcapsules, controlled release, stability. Tropical Journal of Pharmaceutical Research Vol. 6 (4) 2007: pp. 841-84