Optimization of Methotrexate Transdermal Patches: Effect of Variables on In-Vitro, Ex Vivo Permeation and Flux

Background: The aim of the investigation was to develop, optimize and evaluate matrix type transdermal drug delivery systems (TDDS) of Methotrexate (MTX). Methods: The purpose of this study was to develop suitable matrix transdermal therapeutic system of Methotrexate (MTX) with different proportions of hydrophobic [Ethyl cellulose (EC)] and hydrophilic polymers [Hydroxy propyl methy cellulose E15 (HPMC)] by using a D-optimal mixture design. Five formulations run1 to run7 in the ratio of EC:HPMC (8:2,6.5:3.5,6:4,5:5,4:6,3.5:6:5,2:8) were prepared by solvent evaporation technique. The prepared patches were evaluated for physicochemical chemical characteristics, in-vitro release and Ex-vivo permeation studies. The surface of the patches before and after diffusion was examined by Scanning electron microscopy (SEM). The criterion of desirability was employed to optimize the formulation. Results: The in vitro release studies revealed that the drug release from the patches follows Higuchi kinetics (Correlation coefficient between 0.973 ? 0.9949, p