Abstract
The objective of this project was to improve the solubility of poorly water soluble drug namely Carvedilol phosphate by formulating solid dispersions with skimmed milk powder as a carrier. Twelve different formulations were prepared with varying drug: carrier ratios of solid dispersions and the corresponding physical mixtures were also prepared. Various techniques were used to characterize the solid dispersions immediately after they were made which includes Differential Scanning Calorimetry (DSC), X-ray diffraction (XRD), FTIR and in-vitro dissolution studies. The DSC thermogram of pure drug indicated of its anhydrous crystalline nature. In the thermogram of solid dispersion, the characteristic peak was absent suggesting the change from crystalline nature to amorphous form. XRD confirmed the results. XRD results for the Pure drug showed highly intense peaks characteristic of its crystalline nature. The XRD pattern of solid dispersion showed less intense, more diffused peaks indicating an obvious change in the crystalline form. FTRI studies indicated that there was no interaction between the drug and the carrier. All the formulations showed marked improvement in the solubility behavior and improved drug release. Formulation containing drug: polymer ratio of 1:6 showed the best release with a cumulative release of 76.4% as compared to 34.51% for the pure drug. It was concluded that skimmed milk powder as a carrier can be very well utilized to improve the solubility of poorly soluble drugs.
