DESIGN AND DEVELOPMENT OF SUPERPOROUS HYDROGEL OF AN ANTIHYPER-TENSIVE DRUG FOR GASTRORETENTIVE DRUG DELIVERY

Superporous hydrogels (SPHs) is originally developed as a novel drug delivery system to retain drugs in the gastric medium by instant swelling on water absorption through open porous structure and maintain their integrity in that harsh environment. Atenolol, an antihypertensive drug with a short half-life, limited bioavailability, unstable nature at basic pH potentiated the need for developing a gastro-retentive system, hence super porous hydrogel of Atenolol had been developed with cellulosic polymers, and adequate strength was imparted by the addition of Ac- Di- Sol. The structural morphology of hydrogel was investigated by SEM, and it was found that plenty of pores of different size ranges, like 1 mu m, 2 mu m, 10 mu m were formed. Compatibility studies proved the integrity of the super porous hydrogel. Gelation time was found to vary with respect to the formulation. The setting time of super porous hydrogel was found to be increased with an increase in the concentration of HPMC K100M. The drug release from super porous hydrogels was sustained for 10 h. In-vitro drug release data obtained were fitted into various kinetic equations. The formulations obeyed Higuchi and Korsmever- Peppas kinetics of drug release. For further confirmation, the data were fitted to the Kopcha model to get the evidence of drug release by the combination of diffusion-controlled and chain relaxation-swelling mechanism. However, the diffusion mechanism predominated the process leading to quasi diffusion and anomalous diffusion mechanism.