Design, Development & Characterizaton of Microemulsion Based Gel for the Treatment of Acne

Abstract

The purpose of this study was to develop microemulsion based hydrogel formulation for topical delivery of Dapsone (MBG) with an objective to increase the drug solubility and its skin permeation. Triacetin was screened as the oil phase for microemulsion (ME), because of its good solubilizing capacity. The pseudo-ternary phase diagrams for microemulsion region was constructed using Triacetin (oil), Tween 80 (surfactant) and Labrasol (cosurfactant). D-Optimal mixture experimental design was adopted to optimize the amount of oil (X1), amount of Smix (mixture of surfactant and cosurfactant) (X2) and amount of water (X3) in the ME. The design batches were assessed for globule size (nm) (Y1) and solubility of Dapsone in microemulsion (ME) (mg/ml) (Y2). The microemulsion consisting of 5% oil, 64.17% Smix and 30.83% water was selected as the optimized batch of Dalsone loaded ME. The globule size and solubility of Dapsone for optimized DME were 13.20 nm and 173.10 mg/ml respectively. Transmission electron microscopy analysis of optimized batch confirmed the size and sphericity of ME globules. Further, Carbomer 934 was used to convert ME into gel form, without affecting its characteristics, for improving the viscosity of ME to improve its topical applicability. In-vitro permeation study of Dapsone from Dapsone loaded ME, MBG of Dapsone and control gel had shown 88.78%, 81.78% and 58.12% respectively after 8 h. The skin irritation study on rabbit model revealed that MBG of dapsone was safer as compared to Dapsone loaded ME because of its least/no erythema or edema and slight skin irritation in comparison to DME. Thus, it was concluded that developed MBG of Dapsone could be a promising formulation for effective treatment of acne compared to conventional formulations.