Abstract

FORMULATION AND EVALUATION OF SUSTAINED RELEASE DICLOFENAC SODIUM MICROSPHERES USING EUDRAGIT RS100.

T. Mangilal*, K.S.K. Rao Patnaik, E. Nagabhushan, P. Shashikala, D. Jayaprakash

Abstract

The objective of the current investigation is to formulate Eudragit RS100 based sustained release microspheres, containing Diclofenac sodium as a model drug. Diclofenac sodium is a type II antiinflammatory agent. When administered together shows synergistic effect in their action. Microspheres were prepared by O/O emulsion solvent evaporation method with different stabilizer concentration and at different speeds of emulsification while maintaining constant amounts of Diclofenac sodium. Drug excipient compatibility study was performed prior to formulation development and only compatible excipients were used in the fabrication of microspheres. Prepared microsphere formulations were characterized by percentage yield, particle size analysis, entrapment efficiency, in vitro release behavior, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). SEM studies showed that the microspheres were spherical with rough surface morphology. The drug loaded microspheres showed 50-80% entrapment efficiency. The in vitro release profile showed a slow and steady release pattern for Diclofenac sodium. A 100% Diclofenac sodium was released within a period of 12 hrs during this time. The drug release was found to be diffusion controlled mechanism. The n value of Korsmeyer Peppas equation indicated non Fickian type of diffusion. DSC results indicated that the physical state of the drug was changed upon fabrication. As a result of these experiments, it was concluded that, novel sustained release oral microspheres comprising a combination of diclofenac sodium was successfully prepared using eudragit RS100 as the polymer and using emulsion solvent evaluation methods.

Keywords: Microspheres, Diclofenac sodium, Eudragit RS100, O/O Emulsion solvent evaporation method, FTIR, SEM and DSC.