CELLULOSE ACETATE FLOATING MICROSPHERES OF METFORMIN HYDROCHLORIDE: FORMULATION AND CHARACTERIZATION

In this study, floating microspheres of metformin hydrochloride were prepared by using cellulose acetate polymer by solvent evaporation method. Four formulations were prepared by varying the ratio of drug and polymer. The prepared microspheres were then subjected to various evaluation parameters such as drug content, micromeritic evaluations, FTIR, SEM, floatability and in vitro dissolution study. Formulation F1 (1:1 ratio of polymer and drug) showed the highest drug release and drug content with good flow properties. The cumulative percentage of drug release significantly decreased with decreasing drug concentration with a constant polymer ratio. Scanning Electron Microscopy images of all formulations showed that the prepared floating microspheres were irregular in shape, and the surface was found to be non- uniform and rough. In vitro release studies indicated the mechanism of the drug release to follow the Korsemeyer-Peppas model, and “n” value was found to be between 0.54-1.89, indicating anomalous transport mechanism.