During the HypFlow project, we are working on the three following objectives:
1. design and build a pulsed-DNP freeze&flow polarizer apparatus in which pure solutions will be recirculated and repolarized.
We have so far been developing the first version of the HypFlow polarizer operating at 1T and 77K with continuous wave microwave irradiation (30 GHz) and heteronuclear pulsed NMR up to 45 MHz, including CP, and published our work here.
Bocquelet, C.; Rougier, N.; Le, H.-N.; Veyre, L.; Thieuleux, C.; Melzi, R.; Purea, A.; Banks, D.; Kempf, J. G.; Stern, Q.; Vaneeckhaute, E.; Jannin, S. Boosting 1H and 13C NMR Signals by Orders of Magnitude on a Bench. Science Advances 2024, 10 (49), eadq3780.
https://doi.org/10.1126/sciadv.adq3780(s’ouvre dans une nouvelle fenêtre).
Vaneeckhaute, E.; Bocquelet, C.; Rougier, N.; Jegadeesan, S. A.; Vinod-Kumar, S.; Mathies, G.; Melzi, R.; Kempf, J.; Stern, Q.; Jannin, S. Dynamic Nuclear Polarization Mechanisms Using TEMPOL and Trityl OX063 Radicals at 1 T and 77 K. arXiv December 13, 2024.
https://doi.org/10.48550/arXiv.2412.10325(s’ouvre dans une nouvelle fenêtre).
2. Integrate the use of electron-polarized hyperpolarizing matrices.
We have implemented the use of porous polymer polarizing matrices (HYPOPs) with our new polarizer, and we have published our work here.
Vaneeckhaute, E.; Bocquelet, C.; Bellier, L.; Le, H.-N.; Rougier, N.; Jegadeesan, S. A.; Vinod-Kumar, S.; Mathies, G.; Veyre, L.; Thieuleux, C.; Melzi, R.; Banks, D.; Kempf, J.; Stern, Q.; Jannin, S. Full Optimization of Dynamic Nuclear Polarization on a 1 Tesla Benchtop Polarizer with Hyperpolarizing Solids. Phys. Chem. Chem. Phys. 2024, 26 (33), 22049–22061.
https://doi.org/10.1039/D4CP02022G(s’ouvre dans une nouvelle fenêtre).
We have also investigated how hyperpolarization could be transferred during sample flow to the NMR spectrometer.
Stern, Q.; Reynard-Feytis, Q.; Elliott, S. J.; Ceillier, M.; Cala, O.; Ivanov, K.; Jannin, S. Rapid and Simple 13 C-Hyperpolarization by 1 H Dissolution Dynamic Nuclear Polarization Followed by an Inline Magnetic Field Inversion. J. Am. Chem. Soc. 2023, 145 (50), 27576–27586.
https://doi.org/10.1021/jacs.3c09209(s’ouvre dans une nouvelle fenêtre).
In parallel, we have been investigating how these matrices could be filtered out, and we have tested new matrices in which electrons could potentially be polarized.
Pokochueva, E. V.; Le, N. H.; Guibert, S.; Gioiosa, C.; Stern, Q.; Tolchard, J.; Bocquelet, C.; Cala, O.; Cavaillès, M.; Veyre, L.; Mankinen, O.; Telkki, V.-V.; Thieuleux, C.; Jannin, S. Hybrid Polarizing Solids with Extended Pore Diameters for Dissolution Dynamic Nuclear Polarization. Chemistry October 10, 2024.
https://doi.org/10.26434/chemrxiv-2024-6nmt0(s’ouvre dans une nouvelle fenêtre).
Stern, Q.; Verhaeghe, G.; El Daraï, T.; Montarnal, D.; Le, N. H.; Veyre, L.; Thieuleux, C.; Bocquelet, C.; Cala, O.; Jannin, S. Dynamic Nuclear Polarization with Conductive Polymers. Angew Chem Int Ed 2024, e202409510.
https://doi.org/10.1002/anie.202409510(s’ouvre dans une nouvelle fenêtre).