Hyperpolarization of [13C]formate using parahydrogen

• Published in: Journal of Magnetic Resonance Open 2024-12, Vol.21, p.100176, Article 100176
• Main Authors: Burueva, Dudari B., Sviyazov, Sergey V., Chukanov, Nikita V., Mustafin, Nazim R., Salnikov, Oleg G., Chekmenev, Eduard Y., Kovtunov, Kirill V., Koptyug, Igor V.
• Format: Article
• Language: English
• Subjects: hyperpolarization · parahydrogen · PHIP-SAH · formate
• ISSN: 2666-4410; 2666-4410
• DOI: 10.1016/j.jmro.2024.100176

•The feasibility of hyperpolarization of formate using parahydrogen is demonstrated.•The polarization of 16.6 ± 0.6 % for 1H is obtained for allyl [13C]formate.•The corresponding polarization of 13C nuclei in allyl formate is 1.7 ± 0.2 %.•Sodium [13C]formate was hyperpolarized with P13C of 0.4 ± 0.1 %. Sodium [13C]formate was successfully hyperpolarized using parahydrogen-induced polarization by means of side-arm hydrogenation (PHIP-SAH). Allyl [13C]formate was hyperpolarized using homogeneous hydrogenation of the corresponding unsaturated precursor (propargyl [13C]formate) in acetone-d6 with parahydrogen. The observed proton polarization was estimated as 16.6 ± 0.6 % while achieving 80 % chemical conversion. The 1H-to-13C polarization transfer was performed using magnetic field cycling. The highest observed polarization for 13C nuclei was estimated as 1.7 ± 0.2 % and was obtained at 250 nT polarization transfer magnetic field. We demonstrate that the 13C hyperpolarization is retained during the hydrolysis of allyl [13C]formate and hyperpolarized sodium [13C]formate was produced with P13C of 0.4 ± 0.1 %. [Display omitted]