COMPARISON OF IN-VITRO RELEASE RATES OF NITROGLYCERIN BY DIFFUSION THROUGH A TEFLON MEMBRANE TO THE USP METHOD

The in vitro release profile of nitroglycerin (GTN) from different tra nsdermal patches through synthetic membranes has been determined and c ompared to the USP adapted release rate method. Five different nitrogl ycerin transdermal test formulations were compared to commercially ava ilable Nitro-Dur(R). All formulations display similar release rate pro files when tested by the USP adapted release rate method. In contrast, significant differences among the tested formulations were observed b y using a synthetic Teflon membrane. In these studied an attempt was m ade to develop a simple, reliable, and reproducible method for testing the release of GTN from different transdermal patches in vitro.