title: Polymer mobilization and drug release during tablet swelling. A 1H NMR and NMR microimaging study.
abstract: The objective of this study was to investigate the swelling characteristics of a hydroxypropyl methylcellulose (HPMC) matrix incorporating the hydrophilic drug antipyrine. We have used this matrix to introduce a novel analytical method, which allows us to obtain within one experimental setup information about the molecular processes of the polymer carrier and its impact on drug release. Nuclear magnetic resonance (NMR) imaging revealed in situ the swelling behavior of tablets when exposed to water. By using deuterated water, the spatial distribution and molecular dynamics of HPMC and their kinetics during swelling could be observed selectively. In parallel, NMR spectroscopy provided the concentration of the drug released into the aqueous phase. We find that both swelling and release are diffusion controlled. The ability of monitoring those two processes using the same experimental setup enables mapping their interconnection, which points on the importance and potential of this analytical technique for further application in other drug delivery forms.
authors: YKI, Institute for Surface Chemistry, Stockholm, Sweden.
authors: Carina
authors: C
authors: Dahlberg
authors: Anna
authors: A
authors: Fureby
authors: Michael
authors: M
authors: Schuleit
authors: Sergey V
authors: SV
authors: Dvinskikh
authors: István
authors: I
authors: Furó
mesh_terms: D000983:Antipyrine / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D017666:Deuterium Oxide; D004058:Diffusion; D004337:Drug Carriers; D004339:Drug Compounding; D065347:Hypromellose Derivatives; D007700:Kinetics; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008747:Methylcellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D008956:Models, Chemical; D015203:Reproducibility of Results; D012995:Solubility; D013607:Tablets; D013678:Technology, Pharmaceutical / Q000379:methods*; D014867:Water / Q000737:chemistry*
chemical_list: D003692:Delayed-Action Preparations; D004337:Drug Carriers; D013607:Tablets; D014867:Water; D065347:Hypromellose Derivatives; D008747:Methylcellulose; D017666:Deuterium Oxide; D000983:Antipyrine