Different Methods of Formulation and Evaluation of Mucoadhesive Microspheres by using Various Polymers for H2 Receptor Antagonist Drug

Abstract

Ranitidine HCl is a H2 receptor antagonist administered in dose 150 300mg in the treatment of gastric ulcer. The effect of the drug lasts up to 5 h and is poorly bioavailable from the conventional dosage form. A gastroretentive mucoadhesive drug delivery system of Ranitidine HCl was attempted as an alternative to conventional drug delivery system for extended release characteristics. Mucoadhesive microspheres of Ranitidine HCl was developed using Chitosan and Eudragit RS 100 as polymers at different drug to polymer ratios. The mucoadhesive microspheres were developed by different methods such as solvent evaporation, double emulsion, coacervation phase separation. The developed microspheres were screened for physiochemical and in vitro release characteristics. The performance of the microspheres in physiochemical characteristics and in vitro release behaviour were compared. The formulations were coded RCS1 RCS6 (solvent evaporation), RCD1 RCD6 (double emulsion), RCP1 RCP6 (coacervation phase separation) for Chitosan microsphere and RES1 RES6 (solvent evaporation), RED1 RED6 (double emulsion), REP1 REP6 (coacervation phase separation) for Eudragit RS 100 microsphere. Based on the performance of the microspheres in various characteristics as mentioned above were analyzed and the best fit formulations from among Chitosan microspheres and from among Eudragit RS 100 microspheres were RCP3 and RES3 respectively. Formulations RCP3 and RES3 were validated for reproducible results on percentage yield, particle size and entrapment efficiency. The results of the study suggest that the outcome of the mucoadhesive microspheres for sustained delivery of Ranitidine HCl for effective control of ulcer seems influences in the type of polymer and the method of preparation selected. A judicious selection of the appropriate polymer and the processing method can ensure microspheres with the desired release characteristics. Further study in humans may bring out the scope of the microspheres for better management of ulcer in clinical practice.