Abstract

FORMULATION AND CHARACTERIZATION OF RITONAVIR LOADED ETHYL CELLULOSE MICROSPHERES FOR ORAL DELIVERY

Abstract

The objective of the present study was to prepare and evaluate micro particles for the controlled release of Ritonavir using cellulose polymer. The micro particles were prepared by the solvent evaporation method (O/O) using ethyl cellulose as wall materials. In order to increase the encapsulation efficiency, a mixed solvent system comprising 1:1 proportions of ethanol and dichloromethane were used as a dispersed phase. The prepared micro particles were characterized for the percent drug content, entrapment efficiency, FTIR, DSC, scanning electron microscopy (SEM) and in vitro dissolution studies. The prepared micro particles were white, freeflowing, and almost spherical in shape. The drug-loaded micro particles showed 86-111% drug entrapment, mean particle size was in the range of 36-40μm. In vitro drug release studies were carried out up to 10h in two different pH media, i.e., acidic buffer (pH 1.2) and SLS solution (0.7%). FTIR and DSC thermo grams showed the stable character of Ritonavir in the micro particles. SEM showed that the micro particles were porous in nature. The release kinetics study revealed that the prepared micro particles were best fitted to the zero order. The release kinetics data and characterization studies indicated that drug release from microcapsules was diffusion – controlled and that the micro particles were stable.

Keywords: Microspheres, solvent evaporation method, ethyl cellulose, release Kinetics.