Effect of permeation enhancers on the release of ketoprofen through transdermal drug delivery systems.

Feasibility studies were performed to prepare membrane controlled transdermal drug delivery system of ketoprofen containing Carbopol 934p gels. The ability of permeation enhancers such as oleic acid, polyethylene glycol 400 and propylene glycol to provide improved performance has been investigated. The variables studied were drug loading, type of the permeation enhancers, and their concentration. Diffusion studies across Spectra/por 1 membranes were performed using Franz diffusion cells. The medium employed was pH 7.4 phosphate buffer. The permeation parameters such as flux, enhancement ratio, permeation and diffusion coefficients have been evaluated. The results indicated a zero or near zero-order release kinetics. The studies indicated that oleic acid in a concentration of 35% w/w provided the maximum permeation when the ketoprofen concentration in the patches was 5%. Corresponding values of flux,enhancement ratio, permeability and diffusion coefficients were 6.22 micrograms/cm2/h, 8.57, 1.09 x 10(-3) cm/h, and 3.13 x 10(-6) cm3/h respectively. Further, an increase in ketoprofen loading from 5 to 10% increased the permeation.