Preparation of Microspheres of Diclofenac Sodium by Ionotropic Gelation Technique

Diclofenac sodium is a non-steroidal anti-inflammatory drug used in the treatment of arthritis. Treatment with NSAIDs is observed to have gastro intestinal side effects and the formulation of Diclofenac sodium using biodegradable and biocompatible polymer in the form of microspheres is expected to decrease GI side effects. In the present study, different microsphere formulations of Diclofenac Sodium were formulated by Ionotropic Gelation Technique using sodium alginate as carrier and Eudragit S100 as release modifying agent. Microspheres of Diclofenac Sodium prepared in this study were evaluated for flow properties, drug entrapment efficiency and drug release from tablets. Of the various formulations prepared, formulation F4 was found to show satisfactory results. Drug release data was fitted into various kinetic models and was found to be following Michaelis Menten release. Sustained release microspheres of diclofenac sodium were successfully prepared using Ionotropic Gelation Technique and the Tablets containing drug polymer ratio of 1:2 were found to sustain the release of the active substance for 12 hours when examined in pH 7.5 phosphate buffer. These results demonstrate the suitability of the prepared microspheres of Diclofenac sodium as sustained release dosage form.