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15N-Azides as practical and effective tags for developing long-lived hyperpolarized agents† † Electronic supplementary information (ESI) available: Synthesis of (15N)3-azide-tagged molecules, and (15N)-azide-tagged molecules, hyperpolarization experiments, 1H, 13C and 15N-NMR spectra as well as data analysis. See DOI: 10.1039/d1sc04647k

ABSTRACT: Azide moieties, unique linear species containing three nitrogen atoms, represent an attractive class of molecular tag for hyperpolarized magnetic resonance imaging (HP-MRI). Here we demonstrate (15N)3-azide-containing molecules exhibit long-lasting hyperpolarization lifetimes up to 9.8 min at 1 T with remarkably high polarization levels up to 11.6% in water, thus establishing (15N)3-azide as a powerful spin storage for hyperpolarization. A single (15N)-labeled azide has also been examined as an effective alternative tag with long-lived hyperpolarization. A variety of biologically important molecules are studied in this work, including choline, glucose, amino acid, and drug derivatives, demonstrating great potential of 15N-labeled azides as universal hyperpolarized tags for nuclear magnetic resonance imaging applications. This work demonstrates that 15N-labeled azides are practical and effective tags for developing long-lived hyperpolarized MRI agents and can offer hyperpolarization lifetimes up to 9.8 min at 1 T and high polarization levels up to 11.6% in water.

SUBMITTER: Bae J

PROVIDER: S-EPMC8565375 | biostudies-literature |

REPOSITORIES: biostudies-literature

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