Formulation and Characterization of Drug in Adhesive Transdermal Patches of Diclofenac Acid

The purpose of this research was to develop a matrix-type transdermal therapeutic system containing drug Diclofenac acid, Pressure Sensitive Adhesive (PSA) like acrylic adhesive by the solvent evaporation technique. Different concentrations of Labrasol, oleic acid and triacetin were used to enhance the transdermal permeation of diclofenac acid. Polyethylene monolayer film as a backing membrane and Silicone coated polyester film as a release liner preferred in preparation of transdermal patches. Formulated transdermal patches were physically evaluated with regard to percentage moisture absorption, thickness, weight variation, drug content, tensile strength, % elongation, folding endurance. All prepared formulations indicated good physical stability. In vitro skin permeation studies of formulations were performed by using Franz diffusion cells. Formulation containing 5% drug, 85% adhesive solution and 10% triacetin as permeation enhancer showed best in vitro skin permeation through human cadaver skin as compared to all other formulations. The results rate was found to follow zero order kinetics. These results indicate that the formulation F3 has shown optimum release in concentration independent manner. Stability study indicates that drug remains stable for six months and primary irritation study indicated that the transdermal patches are non-irritant.