Strong NMR enhancement: PHIP-X

NMR signals are often too weak for many chemical and biomedical applications such as reaction monitoring or the real time investigation of metabolism in-vivo. A new method has been developed to enhance NMR signals: parahydrogen-induced polarization relayed via proton exchange (PHIP-X). The novel methodology achieves boosts of more than 50,000.

PHIP-X combines strong polarizations obtained from PHIP with the broad applicability of polarization transfer via proton exchange as demonstrated in SABRE-Relay (Signal Amplification by Reversible Exchange). PHIP-X can enhance both ¹H as well as ¹³C signals. The technique was demonstrated to strongly boost the NMR signals of different alcohols, water, lactic acid, pyruvic acid, and glucose.

With such strong and versatile NMR enhancements, PHIP-X provides a new foundation for many potential applications of NMR in chemistry and biomedicine.

K. Them et al., Parahydrogen-Induced Polarization Relayed via Proton Exchange, J. Am. Chem. Soc. 143, 13694 (2021)