Narong SarisutaMont KumpugdeePojawon LawanprasertMahidol University2018-09-072018-09-072000-06-06Drug Development and Industrial Pharmacy. Vol.26, No.6 (2000), 687-691036390452-s2.0-0034024780https://repository.li.mahidol.ac.th/handle/20.500.14594/25867The physical structure and drug-polymer interactions of theophylline in Eudragit Ll00, shellac, polyvinyl acetate phthalate (PVAP), cellulose acetate phthalate (CAP), hydroxypropylmethylcellulose acetate phthalate (HPMCP), and hydroxypropylmethylcellulose (HPMC) were studied. The drug-polymer films were prepared by casting and were characterized using powder X-ray diffractometry (PXRD), nuclear magnetic resonance (NMR) spectroscopy, and thin-layer chromatography (TLC). Theophylline was found to recrystallize in the modification II form in all kinds of polymers, which was the same as that recrystallized solely from the solvent system and the original powder. The PXRD and NMR results indicated a superficial drug-polymer interaction between theophylline and Eudragit L100, while there was no evidence of interaction for the others. No drug decomposition was observed by TLC for all drug- polymer mixtures.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyChemistryPharmacology, Toxicology and PharmaceuticsArticleSCOPUS10.1081/DDC-100101285