Abstract

FORMULATION AND EVALUATION OF GASTRO-RETENTIVE FLOATING MICROSPHERE

*Prof. Jyoti Bhushan Khedekar, Komal Wakode, Prof. Swati Laxman Khedekar, Prof. Pooja Radhakrushna Gawandar and Prof. Ganesh Kashinath Bahekar

.

Abstract

The aim of present study is to decrease low oral bioavailability limitations of conventional dosage forms and provide a therapeutic amount of drug to the desired site in the body and maintain the desired plasma concentration of the drug for a particular period of time. Rilpivirine hydrochloride an anti-viral drug, choice in the treatment of HIV has been chosen as a model drug in the formulation of controlled drug delivery systems. Various studies reported the absolute oral bioavailability of Rilpivirine hydrochloride (46%) with a half-life of 3- 5 hrs. A microparticulate floating drug delivery system was planned for Rilpivirine hydrochloride as such a system maintain desired concentration to the desired site and improve bioavailability of the drug. Microsphere formulations were prepared using solvent evaporation technique using Xanthan gum and Guar gum. The prepared floating microspheres were characterized for their percentage yield, particle size, morphology, drug entrapment, in-vitro release, and drug release studies. Almost all the formulations showed fairly acceptable values for all the parameters evaluated. Further, the analysis of the release mechanism was carried out by fitting the drug diffusion data to various kinetic equations. The overall curve fitting into various mathematical models was found to be average and best fitted into the zero-order kinetic model. A stability study was conducted for the prepared microspheres of selected formulations for 60 days. There was no significant change in the drug entrapment and in-vitro release study of the microspheres.

Keywords: Microparticulate, drug entrapment, percentage yield, microspheres, drug diffusion.