ATR-FTIR spectroscopic imaging to study the drying and dissolution of pharmaceutical polymer-based films

Pharmaceutical film dosage forms have recently become of interest to pharmaceutical formulation development, particularly for patients who experience difficulty in swallowing tablets or capsules. Furthermore, formulation scientists require a reliable analytical approach to reveal vital insight and investigate the drying process of these films to consolidate suitable quality control. Since most of the polymer-based films containing a drug are produced via solution or dispersion states, an estimation of the physicochemical properties of drugs during drying and dissolution is critical to design novel formulations with the consideration to control drug release, i.e. safety and efficacy to patients. This work presents the novel application of attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopic imaging to study the drying process and dissolution behaviour of polymer-based films. Two types of the ibuprofen containing films, hydroxypropyl methylcellusose (HPMC) based films for immediate release and polyvinylpyrrolidone (PVP) based films for extended release, were studied in modified pH environments and changing hydrophobicity. ATR-FTIR imaging has revealed important information on water ingress into the films and the presence, distribution, and physicochemical state of the drug. ATR-FTIR imaging is a powerful technique to investigate and to deeply understand physicochemical processes for pharmaceutical polymer-based films.