The purpose of this research was to formulate and characterize solid dispersion (SD) of metformin hydrochloride using methocel K100M as the carrier by the solvent evaporation and cogrinding method. The influence of drug polymer ratio on drug release was studied by dissolution tests. Characterization was performed by fourier transform spectroscopy (FTIR), ultraviolet, differential scanning calorimetry and X-ray powder diffractometry. The optimized formulation was subjected to accelerated stability testing as per ICH guidelines. Release data were examined kinetically. SD with 1:4 and 1:5 ratio of drug to polymer obtained by solvent evaporation and cogrinding were selected as the best candidates suitable for prolonged-release oral dosage form of metformin.
Key words: Cogrinding, metformin, methocel, solid dispersion, solvent evaporation.