Abstract

FORMULATION, DESIGN AND CHARACTERIZATION OF MICROEMULSION BASED SYSTEM FOR TOPICAL DELIVERY OF ANTIPSORIATIC DRUG

Nirmal Shah*, Avinash Seth, Sachin Chauhan, Chintan Aundhia, Ankur Javia, Girish Sailor

ABSTRACT

The purpose of this study was to develop a stable methotrexate (MTX) loaded microemulsion gel (MMG) for topical use in psoriasis to improve cutaneous deposition and local effect. The pseudo-ternary phase diagrams were developed for various microemulsion formulations composed of Capmul MCM - C8 as oil phase, Tween 20 as surfactant and polyethylene glycol 400 (PEG 400 as cosurfactant. Composition of microemulsion system was optimized using concentration of oil, surfactant/cosurfactant (1:1) and water as independent variables. The MTX- loaded microemulsion was characterized by droplet size and zeta potential. Microemulsion gel was prepared by adding 1% Carbopol 934 as a gelling agent. The transdermal ability of MTX from microemulsion gel was evaluated by in vitro permeation study. The results shows that optimized microemulsion formulation was composed Capmul MCM - C8 (7.5% w/w), Tween 20 (37.5% w/w), PEG 400 (12.5% w/w) and water (42.5% w/w). The optimized microemulsion was found to be relatively uniform in size of optimized (11.52 ± 0.6 nm). The MMG showed enhanced in vitro permeation ability with better drug deposition capacity compared MTX solution, gel and microemulsion. The results suggest that the MMG is promising formulation for topical delivery of MTX for psoriasis treatment.

Keywords: Methotrexate; Microemulsion; Microemulsion gel; Topical delivery; Antipsoriatic.