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Nanostructure of Materials Determined by Relayed Paramagnetic Relaxation Enhancement.

ABSTRACT: Particle and domain sizes strongly influence the properties of materials. Here we present an NMR approach based on paramagnetic relaxation enhancement (PRE) relayed by spin diffusion (SD), which allows us to determine lengths in the nm-?m range. We demonstrate the method on multicomponent organic polymer mixtures by selectively doping one component with a paramagnetic center in order to measure the domain size in a second component. Using this approach we determine domain sizes in ethyl cellulose/hydroxypropyl cellulose film coatings in pharmaceutical controlled release formulations. Here we measure particle sizes ranging from around 50 to 200 nm.

SUBMITTER: Schlagnitweit J

PROVIDER: S-EPMC4598824 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Nanostructure of Materials Determined by Relayed Paramagnetic Relaxation Enhancement.

Schlagnitweit Judith J Tang Mingxue M Baias Maria M Richardson Sara S Schantz Staffan S Emsley Lyndon L

Journal of the American Chemical Society 20150928 39

Particle and domain sizes strongly influence the properties of materials. Here we present an NMR approach based on paramagnetic relaxation enhancement (PRE) relayed by spin diffusion (SD), which allows us to determine lengths in the nm-μm range. We demonstrate the method on multicomponent organic polymer mixtures by selectively doping one component with a paramagnetic center in order to measure the domain size in a second component. Using this approach we determine domain sizes in ethyl cellulos ...[more]

PMID: 26397956

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