2023 journal article

Parahydrogen‐Induced Carbon‐13 Radiofrequency Amplification by Stimulated Emission of Radiation

Angewandte Chemie International Edition.

By: C. Nelson n, A. Schmidt*, I. Adelabu*, S. Nantogma*, V. Kiselev*, A. Abdurraheem*, H. Maissin*, S. Lehmkuhl* ...

author keywords: Carbon-13; Hyperpolarization; NMR Spectroscopy; Parahydrogen; RASER
Source: ORCID
Added: December 20, 2022

The feasibility of Carbon-13 Radiofrequency (RF) Amplification by Stimulated Emission of Radiation (C-13 RASER) is demonstrated on a bolus of liquid hyperpolarized ethyl [1-13 C]acetate. Hyperpolarized ethyl [1-13 C]acetate was prepared via pairwise addition of parahydrogen to vinyl [1-13 C]acetate and polarization transfer from nascent parahydrogen-derived protons to the carbon-13 nucleus via magnetic field cycling yielding C-13 nuclear spin polarization of approximately 6 %. RASER signals were detected from samples with concentration ranging from 0.12 to 1 M concentration using a non-cryogenic 1.4T NMR spectrometer equipped with a radio-frequency detection coil with a quality factor (Q) of 32 without any modifications. C-13 RASER signals were observed for several minutes on a single bolus of hyperpolarized substrate to achieve 21 mHz NMR linewidths. The feasibility of creating long-lasting C-13 RASER on biomolecular carriers opens a wide range of new opportunities for the rapidly expanding field of C-13 magnetic resonance hyperpolarization.