Abstract

FORMULATION AND IN-VITRO EVALUATION OF GASTRO RETENTIVE NEVIRAPINE CUBOSOME DISPERSIONS AND GELS

M. Sunitha Reddy* and R. Swathi

ABSTRACT

Nevirapine is a BCS class-II antiretroviral drug used in treatment of HIV-1 Infection and AIDS having a Biological half life 45 hours. The aim of the present work is to formulate and evaluate a sustained release formulation of Nevirapine in form of cubosomes and Gastro-retentive gels of cubosomes. The drug, excipients and formulation are characterized by FTIR. Cubosomes are prepared by Top down approach employing Glyceryl monooleate (GMO) as lipid phase vehicle, Pluronic F127 as stabilizer and distilled water as aqueous phase, Nevirapine as active pharmaceutical ingredient. The resultant cubosome dispersion is evaluated for drug release by diffusion studies and visualized by optical microscopy. Floating gels are prepared in a manner similar to cubosome dispersion employing gelling agents like Sodium alginate, Guar gum, Xanthan gum, Carbopol 934 B.P. The formulated gels are evaluated for viscosity, gelation property, pH and drug release by diffusion studies. The compatibility studies by infrared spectroscopy showed no interaction between the drug and excipients. Cubosome formulation RF5 containing 25% GMO showed a maximum drug release of 93% within 5 hours. The concentration of GMO from above optimized cubosome formulation is used in formulation of gels. Sustained release up to 8 hours was observed in gels formulated with carbopol 934, guar gum and Sodium alginate (RFCNG). In vitro release kinetics exhibited sustained release and followed non Fickian diffusion and secondary case 2 by the optimized formulations. Cubosomes formulated with GMO serves as potential gastro retentive sustained drug delivery vehicle. Further sustained release will be achieved when they are formulated as gels.

Keywords: Cubosome, GMO, Gastro retentive, in-situ gel, Lyotropic liquid crystal, oral drug delivery.