DEVELOPMENT OF A SKIN PERMEATION CELL TO SIMULATE CLINICAL-STUDY OF IONTOPHORETIC TRANSDERMAL DELIVERY

A new single-compartment iontophoretic skin permeation cell was developed to simulate the clinical application of iontophoretic devices. The stability and permeation kinetics of LHRH, the model peptide, were investigated in this new permeation cell (cell design A) using two analytical methods and compared with a commonly used skin permeation cell (cell design B). A polyacrylamide-based hydrogel device was fabricated as the drug reservoir for the iontophoretic transdermal delivery of LHRH. The skin permeation profiles of LHRH were found identical for both permeation cells when assayed by radioactivity measurement. However, cell design A gave a skin permeation profile that was substantially higher than that obtained in cell design B when assayed by HPLC. This is because the electrochemical degradation of LHRH occurred in the receptor compartment of the Valia-Chien permeation cell (cell design B). This degradation could be overcome by using the new single-compartment iontophoretic permeation cell.