Effect of Drug Loading and Process Temperature on Physicochemical Properties of Manidipine Hydrochloride Solid Dispersion
Binary solid dispersions of manidipine hydrochloride (MDP) and polyethylene glycol (PEG) 4000 are prepared by melting method. Drug loading and process temperature are varied in the range of 5-30% and 150-210°C, respectively. After melting, only the formulation using 5% MDP and process temperature of 210°C showed yellow clear solution and halo pattern of powder X-ray diffractograms with the absence of peaks. These results indicated that the higher process temperature (210°C) can melt all MDP powders and provide the amorphous product. Moreover, only the higher carrier content can change the crystalline form of MDP to the amorphous form. A clear, solid solution could not be prepared when the drug loading was higher than 5%. In this study, the melting technique avoiding the use of organic solvent was successfully applied to prepared binary solid dispersion.