Hung-Hong Lin, Po-Chun Wang, Li-Tung Hung and Li-Ren Hsu Evaluation of in Vitro Release Profiles of Developed Membrane- moderated Transdermal Delivery Systems Containing

Membrane permeation-controlled transdermal delivery devices for the controlled delivery of methylephedrine HCl were developed using calcium alginate membrane as rate-controlling membrane. To increase the solubility of methylephedrine HCl in the systems, HPMC and agar binary gel was used as drug reservoir. In vitro drug release studies were carried out using modified Franz diffusion cells. The result shows that the step of drug penetrating through the calcium alginate membrane is rate-limiting, then the rate of drug release from the patch is considered to be membrane controlled. The release kinetics of ointment and patch may be square root time dependent and the highest regression coefficient was obtained with the Higuchi model. The surface permeability of ointment was reduced by crosslinking of the membranes and enable drug continuous release over prolonged periods. Above results will be helpful to possible development of rate-controlling membrane transdermal delivery systems for the other drugs