Stabilisation of amorphous drugs under high humidity using pharmaceutical thin films.

In this study, the stabilization effects of three polymers on four model drugs (felodipine, fenofibrate, carbamazepine, and celecoxib) under saturated humidity were investigated. Three different types of thin films (solid dispersions, drug films with a polymer film coating and drug films laid on top of polymer coated surfaces) were prepared and compared with films containing the drug alone. ATR-FTIR spectroscopy, polarised light microscopy (PLM), scanning electron microscopy (SEM) and nano-thermal analysis (nano-TA) were performed on the model systems after storage under saturated humidity.