Physical evaluation of a new patch made of a progestomimetic in a siliconematrix

The adhesion of a new Transdermal Therapeutic System (TTS) made of silicone and loaded with a progestomimetic drug was characterised. The goal of this study was to use well-known methods or to adapt them to collect representa tive data. individually, methods such as surface tension, peel test and rhe ology are already widely used. Results show that the choice of a substrate for peel tests can be made in the light of surface tension data and that po lymers like poly(tetrafluoroethylene) (PTFE) are good alternatives to skin. Peeling characterisations an made a function of thickness of films, drug c ontent in active, conditions of preparation and conditions of use such as p ressure. Dynamic rheology is more difficult to link to other methods as it mainly reflects internal phenomena and properties that arise in the bulk, a s opposed on its surface. Master curves enable results to be used more easi ly, but the theories to interpret the data are still not powerful enough to replace peel testing. (C) 2000 Elsevier Science B.V. All rights reserved.