Boosting <sup>1</sup>H and <sup>13</sup>C NMR signals by orders of magnitude on a bench.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39630888.
- Also identified by DOI 10.1126/sciadv.adq3780 and PMC identifier 11616688.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Sensitivity is often the Achilles' heel of liquid-state nuclear magnetic resonance (NMR) experiments. This problem is perhaps most pressing at the lowest fields (e.g., 80-MHz <sup>1</sup>H frequency), with rapidly increasing access to NMR through benchtop systems, but also sometimes for higher-field NMR systems from 300 MHz to 1.2 GHz. Hyperpolarization by dissolution dynamic nuclear polarization (dDNP) can address this sensitivity limitation. However, dDNP implies massive and complex cryogenic and high-field instrumentation, which cannot be installed on the bench. We introduce here a compact helium-free 1-T tabletop polarizer as a simple and low-cost alternative. After freezing and polarizing the frozen analyte solutions at 77 K, we demonstrate <sup>1</sup>H signal enhancement factors of 100, with rapid 1-s buildup times. The high polarization is subsequently transferred by <sup>1</sup>H→<sup>13</sup>C cross polarization (CP) to <sup>13</sup>C spins. Such a simple benchtop polarizer, in combination with hyperpolarizing solid matrices (HYPSOs), may open the way to replenishable hyperpolarization throughout multiple liquid-state NMR experiments.