title: Spectroscopy of polymer/drug formulations processed with supercritical fluids: in situ ATR-IR and Raman study of impregnation of ibuprofen into PVP.
abstract: In situ ATR (attenuated total reflectance)-IR spectroscopy has been used to study poly(vinylpyrrolidone) (PVP) films subjected to a solution of ibuprofen in supercritical CO2. The process of impregnation of ibuprofen into PVP has been monitored in situ. It has been shown that the supercritical fluid impregnation process results in ibuprofen being molecularly dispersed in a polymer matrix with ibuprofen molecules interacting with the C=O group of PVP. Raman spectra of ibuprofen impregnated into PVP from supercritical fluid solution have also been measured and compared with the Raman spectra of crystalline ibuprofen. ATR-IR spectroscopy has also revealed specific interactions between the C=O groups of PVP and CO2. Impregnation of ibuprofen into PVP makes the C=O groups of PVP less available for interactions with CO2. It has also been demonstrated that the presence of ibuprofen in PVP also affects sorption of water into PVP.
authors.affiliation: Department of Chemical Engineering and Chemical Technology, Imperial College of Science, Technology and Medicine, Prince Consort Road, SW7 2BY, London, UK. s.kazarian@ic.ac.uk
authors.forename: S G
authors.initials: SG
authors.lastname: Kazarian
authors.forename: G G
authors.initials: GG
authors.lastname: Martirosyan
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical; D007052:Ibuprofen / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011205:Povidone / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013059:Spectrum Analysis, Raman
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D011108:Polymers; D011205:Povidone; D007052:Ibuprofen