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Nanometer size silicon particles for hyperpolarized MRI.

ABSTRACT: Hyperpolarized silicon particles have been shown to exhibit long spin-lattice relaxation times at room temperature, making them interesting as novel MRI probes. Demonstrations of hyperpolarized silicon particle imaging have focused on large micron size particles (average particle size (APS)?=?2.2 ?m) as they have, to date, demonstrated much larger polarizations than nanoparticles. We show that also much smaller silicon-29 particles (APS?=?55?±?12?nm) can be hyperpolarized with superior properties. A maximum polarization of 12.6% in the solid state is reported with a spin-lattice relaxation time of 42?min at room temperature thereby opening a new window for MRI applications.

SUBMITTER: Kwiatkowski G

PROVIDER: S-EPMC5554256 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Nanometer size silicon particles for hyperpolarized MRI.

Kwiatkowski Grzegorz G Jähnig Fabian F Steinhauser Jonas J Wespi Patrick P Ernst Matthias M Kozerke Sebastian S

Scientific reports 20170811 1

Hyperpolarized silicon particles have been shown to exhibit long spin-lattice relaxation times at room temperature, making them interesting as novel MRI probes. Demonstrations of hyperpolarized silicon particle imaging have focused on large micron size particles (average particle size (APS) = 2.2 μm) as they have, to date, demonstrated much larger polarizations than nanoparticles. We show that also much smaller silicon-29 particles (APS = 55 ± 12 nm) can be hyperpolarized with superior propertie ...[more]

PMID: 28801662

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