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Room temperature hyperpolarization of nuclear spins in bulk.

ABSTRACT: Dynamic nuclear polarization (DNP), a means of transferring spin polarization from electrons to nuclei, can enhance the nuclear spin polarization (hence the NMR sensitivity) in bulk materials at most 660 times for (1)H spins, using electron spins in thermal equilibrium as polarizing agents. By using electron spins in photo-excited triplet states instead, DNP can overcome the above limit. We demonstrate a (1)H spin polarization of 34%, which gives an enhancement factor of 250,000 in 0.40 T, while maintaining a bulk sample (? 0.6 mg, ? 0.7 × 0.7 × 1 mm(3)) containing >10(19) (1)H spins at room temperature. Room temperature hyperpolarization achieved with DNP using photo-excited triplet electrons has potentials to be applied to a wide range of fields, including NMR spectroscopy and MRI as well as fundamental physics.

SUBMITTER: Tateishi K

PROVIDER: S-EPMC4040576 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Room temperature hyperpolarization of nuclear spins in bulk.

Tateishi Kenichiro K Negoro Makoto M Nishida Shinsuke S Kagawa Akinori A Morita Yasushi Y Kitagawa Masahiro M

Proceedings of the National Academy of Sciences of the United States of America 20140512 21

Dynamic nuclear polarization (DNP), a means of transferring spin polarization from electrons to nuclei, can enhance the nuclear spin polarization (hence the NMR sensitivity) in bulk materials at most 660 times for (1)H spins, using electron spins in thermal equilibrium as polarizing agents. By using electron spins in photo-excited triplet states instead, DNP can overcome the above limit. We demonstrate a (1)H spin polarization of 34%, which gives an enhancement factor of 250,000 in 0.40 T, while ...[more]

PMID: 24821773

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