In-vitro release study of Diclofenac sodium from topical gel formulations using diffusion cell

Abstract

The present research study was to explore the in-vitro drug release and kinetics of different brands of diclofenac sodium gel formulations (Brand A, B, C) available in the local pharmaceutical market of Tamilnadu with a lab made reference gel by using vertical diffusion cell through synthetic membrane. For this study, three widely prescribed brands of topical gel formulations (Brand A, B, C) were chosen. All of these brands were containing 1% of diclofenac sodium as active drug. The drug release study was carried out using vertical diffusion cell apparatus and the analysis was performed with UV spectroscopy. To find out the release kinetics, it was interpreted with various mathematical models like zero order, first order, Higuchi model and Korsmeyer-peppas model. The R2 value for each kinetic model was also determined which indicated the linearity of release kinetics for each brand. It was found that all the brands tend to follow zero order kinetics that fits into Higuchi model. From the results obtained, Brand B of commercial gel formulation was found to be similar to that of the reference gel formulation. Difference in vehicle components was found to contribute to the difference in drug release of the other brands. And the study assumes that the available brands of Diclofenac sodium gel topical formulations in Tamilnadu generally follow zero order release kinetics that fits into Higuchi model.