Abstract

Sustained release dosage form of diclofenac sodium containing immediate and controlled release components was designed. Solid dispersion of immediate release component was prepared using polyvinyl pyrrolidone and mannitol carriers by common solvent method. Controlled release component was prepared in form of spherical beads by ionotropic gelation technique. The beads were prepared based on dispersing drug in solutions of ionic polysaccharides such as chitosan and sodium alginate. These dispersions were dropped into solutions of counter ions such as tetrasodium pyrophosphate and calcium chloride, respectively. The beads were also prepared using agar by dropping agar-drug hot solution into a mixture of chilled liquid paraffin and water. Then, diclofenac sodium controlled release drug delivery systems were prepared by combining the immediate release and controlled release components in different ratios. The formulations were found to be effective in providing controlled release of drug for a longer period of time. The beads were characterized by scanning electron microscopy and X-ray diffraction studies.