Abstract

Microsponges are tiny, true sponge-like spherical polymeric particles that consist of myriad of interconnecting voids within a non-collapsible structure with large porous surface. This results in a large reservoir within each microsponge, which can be loaded upto its own weight of active agents. The objective of the present work is to formulate a microsponge drug delivery system entrapped with bifonazole (BFZ) having controlled drug release with maximum antifungal activity. Microsponges were prepared using aqueous emulsion diffusion evaporation method. The gel phase was prepared by dispersing carbopol 940 in purified water and allowed to soak. Microsponges containing BFZ equivalent to 1%w/w were dispersed in propylene glycol. Preservatives were dissolved in the purified water. Aqueous solution was then mixed thoroughly into the microsponge containing solution. Finally, gel phase was incorporated into microsponge containing solution with stirring and the pH was adjusted to 6-6.5. Optimized microsponge based gel formulation showed slower flux of drug as compared to marketed formulation indicating controlled release of drug. No significant change in physical appearance as well as % drug content of optimum formulation was observed over the time period of stability studies. The BFZ loaded microsponge based gel was found to have good appearance, other micromeritic properties and entrapment efficiency along with controlled in vitro release profile of drug. Since BFZ, ethyl cellulose as well as carbopol has been reported as nonirritant for skin. The final formulation will not be irritating to skin. On the other ground of efficacy, avoidance of periods of over and under medication and improved patient compliance, microsponge based gel of BFZ will have better role in treating fungal infection of skin.