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Design of a ¹⁵N Molecular Unit to Achieve Long Retention of Hyperpolarized Spin State.

ABSTRACT: Nuclear hyperpolarization is a phenomenon that can be used to improve the sensitivity of magnetic resonance molecular sensors. However, such sensors typically suffer from short hyperpolarization lifetime. Herein we report that [¹⁵N, D₁₄]trimethylphenylammonium (TMPA) has a remarkably long spin-lattice relaxation time (1128?s, 14.1?T, 30?°C, D₂O) on its ¹⁵N nuclei and achieves a long retention of the hyperpolarized state. [¹⁵N, D₁₄]TMPA-based hyperpolarized sensor for carboxylesterase allowed the highly sensitive analysis of enzymatic reaction by ¹⁵N NMR for over 40?min in phophate-buffered saline (H₂O, pH 7.4, 37?°C).

SUBMITTER: Nonaka H

PROVIDER: S-EPMC5220364 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Design of a 15N Molecular Unit to Achieve Long Retention of Hyperpolarized Spin State.

Nonaka Hiroshi H Hirano Masashi M Imakura Yuki Y Takakusagi Yoichi Y Ichikawa Kazuhiro K Sando Shinsuke S

Scientific reports 20170109

Nuclear hyperpolarization is a phenomenon that can be used to improve the sensitivity of magnetic resonance molecular sensors. However, such sensors typically suffer from short hyperpolarization lifetime. Herein we report that [15N, D14]trimethylphenylammonium (TMPA) has a remarkably long spin-lattice relaxation time (1128 s, 14.1 T, 30 °C, D2O) on its 15N nuclei and achieves a long retention of the hyperpolarized state. [15N, D14 ...[more]

PMID: 28067292

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