Carvedilol being a BCS class II drug has low solubility and it has short half-life of 2-6 hrs. The objective of the study is to design, develop and optimize carvedilol microspheres using factorial design. Solubility was enhanced by formulating into solid dispersion using solvent evaporation technique and solid dispersion with enhanced solubility was incorporated into sodium alginate microspheres prepared by ionic gelation method and were optimized by 3-level, 2-factor full factorial design. Solid dispersion formulation SD3 showed 15.3 folds enhanced solubility compared to the pure drug. Powder X-ray Diffractogram patterns revealed that the crystalline drug was transformed into an amorphous form. SD3 formulation was incorporated into sodium alginate microspheres and the microspheres were optimized. The optimized microsphere formulation had an entrapment efficiency of 79.41% and showed 80% drug release at 6 hrs. Scanning electron microscopic images proved, that optimized microspheres were spherical in shape and had rough surface.
