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PubMed · 9803942

Self-diffusion and molecular mobility in PVA-based dissolution-controlled systems for drug delivery.

J E Snaar·R Bowtell·C D Melia·S Morgan·B Narasimhan·N A Peppas
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Abstract

Nuclear magnetic resonance (NMR) microscopy has been used to monitor the hydration of poly(vinyl alcohol) (PVA) samples of varying molecular weight. One-dimensional profiles weighted to predominantly show the variation of water concentration were acquired every 3 min during the first 30 min of hydration and subsequently at 1 and 2 h. Diffusion-weighted profiles obtained after 30 min and 1 and 2 h were used to calculate the spatial variation of the water self-diffusion coefficient. The resulting data provide supporting evidence for the hypothesis that phenomena such as reptation are important near the glassy/rubbery interface of polymers during dissolution, while the diffusion gradually changes to Zimm type near the rubbery/solvent interface.

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DiffusionDrug Delivery SystemsHumansMagnetic Resonance SpectroscopyMicroscopyMolecular WeightPolyvinyl AlcoholTabletsWaterJournal ArticleResearch Support, Non-U.S. Gov't

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J E Snaar, R Bowtell, C D Melia, S Morgan, B Narasimhan, N A Peppas. Self-diffusion and molecular mobility in PVA-based dissolution-controlled systems for drug delivery.. https://doi.org/10.1016/s0730-725x(98)00021-6

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