Formulation and evaluation of microsponge gel for topical delivery of fluconazole for fungal therapy

The aim of the present research was to develop Fluconazole loaded microsponge-based topical delivery system for controlled release and enhanced drug deposition in the skin. Microsponges containing fluconazole were prepared by an emulsion solvent diffusion method. The effect of formulation variables (drug: polymer ratio, internal phase volume and amount of emulsifier) and process variables (stirring time and stirring speed) on the physical characteristics of microsponges like Production yield, Mean particle size, Entrapment efficiency were investigated. The effect of internal phase volume and amount of emulsifier on the physical characteristics of microsponges were examined on optimized drug/polymer ratio, stirring speed and stirring time by 32factorial design. The optimized microsponges were dispersed into a hydrogel and evaluated. In vitro drug release, Ex vivo drug deposition, primary skin irritancy study and In vivo antibacterial activity of fluconazole-loaded formulations were studied. Spherical and porous FLU microsponge particles were obtained. From 32factorial design, it was concluded that optimized microsponge possess particle size, production yield and entrapment efficiency of 2.45 μm, 77.38 and 92.33 %, respectively. Microsponge-loaded gels demonstrated controlled release, no irritancy to rat skin and antifungal activity. An In vivo skin deposition study demonstrated four fold higher retention in the stratum corneum layer as compared with marketed cream. Microsponges-based gel formulations showed prolonged efficacy in mouse surgical wound model infected with Candida spp. Fluconazole was stable in topical formulations and showed enhanced retention in the skin indicating better potential of the delivery system for treatment of primary and secondary skin infections. © 2016, The Korean Society of Pharmaceutical Sciences and Technology.