EXPLOITATION OF SECOND GENERATION SUPERPOROUS HYDROGEL COMPOSITES AS MATRIX RETARDANTS, IN GEL COATING OF PREGABALIN FORMULATION AND IN-VIVO CHARACTERIZATION

The hydro dynamically balanced gastro retentive systems of Pregabalin has been formulated and evaluated which can retard the release of drug based on Super Porous Hydrogel Composites (SPHC) thereby prolong the release rate specifically in the upper part of the GIT. Fast swelling highly porous SPHCs are synthesized by gas blowing technique. The swelling property, mechanical strength and release profile of SPHCs containing drug was investigated by changing the amount of cross-linking agents such as N,N¹-methylene-bis acrylamide (BIS) and Ac-Di-Sol. SPHCs to powder form was prepared, the obtained powder material used as matrix agent for the preparation of tablets. Floating tablets were prepared by wet granulation, novel melt granulation and direct compression methods using various grades of ethyl cellulose, HPMCK 100, eudragit ESPO, geleol, compritol 888 ATO and SPHC powder in different concentrations. The prepared gastro retentive floating tablets were evaluated in-vitro buoyancy studies, in–vitro and in-vivo release studies. Formulations consisting powdered SPH Ac-Di-Sol composite as matrix agent was optimized. The floating time observed >12 h at pH 1.2. The in–vitro release studies revealed that the drug release was in controlled fashion up to 12 hrs. Pregabalin non effervescent buoyant tablet formulations (F14, F15 and F16) employing powdered SPH Ac-Di-Sol composite itself as matrix agent were selected for the novel dry gel coating by SPH Ac-Di-Sol composite. GF14 formulation optimized for in-vivo studies due to its effective retarding capability up to 12 h. Using Higuchi’s model and the Korsmeyer equation, the drug release mechanism from the floating controlled release tablets was found to be anomalous (non-Fickian) diffusion.