Anna Mlynarczyk1, Krzysztof Jasinski1, Piotr Kulinowski1, Marco L. H. Gruwel2, Przemysaw Dorozynski3, Boguslaw Tomanek1,2, Wladyslaw P. Weglarz1
1Department of Magnetic Resonance Imaging, Institute of Nuclear Physics PAN, Krakow, Poland; 2Institute for Biodiagnostics, National Research Council of Canada, Winnipeg, Manitoba, Canada; 3Department of Pharmaceutical Technology & Biopharmaceutics, Jagiellonian University, Krakow, Poland
MRI time-resolved approach was used to measure spatial distribution of T2 and PD of HPMC-based tablets during hydration. Biexponential T2 data analysis approach was used to distinguish regions with different water organization and molecular mobility. Influence of two active substances, that are freely (L-dopa) and poorly (Ketoprofen) soluble on matrix structure during hydration was tested. In all cases hydrated area consists of several separated sub-areas (layers) with well-defined properties: dry-glassy-polymer, infiltration-layer, solid-swollen-layer, gel-layer. Subpixel-level heterogeneity during hydration was clearly visible. In case of Ketoprofen formulation, gel layer area is not present which has great influece on drug dissolution during hydration.