Simulating Non‐linear Chemical and Physical (CAP) Dynamics of Signal Amplification By Reversible Exchange (SABRE)

Abstract

What is the most significant result of this study?Signal amplification by reversible exchange (SABRE) with parahydrogen is au nique method to boost the NMR signal by several orders of magnitude. Many effects that govern SABRE were described before, or at least mentioned in the literature. Ac omprehensive model bringing together the separate pieces, however, was missing so far.T his is what we did here.Invited for the cover of this issue are Andrey N. Pravdivtsev and Jan-Bernd Hçvener from Kiel University.T he image depicts the essential steps that were used to model NMR signal amplification by reversible exchange (SABRE), much more thoroughly than before. Read the full text of the article at

Continuous Radio Amplification by Stimulated Emission of Radiation using Parahydrogen Induced Polarization (PHIP‐RASER) at 14 Tesla

“…Depending on the simulated experiment, different source operators can be used. Simulations were performed using the MOIN spin library; the source code is available online …”

A role for low concentration reaction intermediates in the signal amplification by reversible exchange process revealed by theory and experiment

“…Hence the results portrayed here detail a route to probe for reaction intermediates in catalysis based on how they affect the evolution of polarisation under SABRE as a function of temperature. While a range of theoretical studies have been reported that detail how the propagation of spin polarisation during SABRE occurs, it is clear that if theoretical predictions 20,30,31,38,39 are to accurately map onto experimental data, 40 they will need to take into account contributions from a range of species in solution. We expect that these results will be of interest to those seeking to model SABRE and those involved more generally in the study of catalysis.…”

“…4,9,10 Consequently, the efficiency of SABRE is highly dependent on the lifetime of the complex which must match the propagating resonance condition leading to transfer. [11][12][13] It also relies on setting the magnetic field the sample experiences during the transfer step to a value of around 60 G when 1 H nuclei are targeted, but much lower mG fields are needed for 15 N and 13 C nuclei. [14][15][16] Given these constraints, the level of NMR signal enhancement can be improved through catalyst design and by sharing the hyperpolarisation source p-H 2 with fewer receptor spins in conjunction with deuterium labelling which also reduces relaxation effects.…”

Hyperpolarization of Pyridyl Fentalogues by Signal Amplification By Reversible Exchange (SABRE)

“…The role of level‐anti‐crossings in the transfer of polarization has also been explored, and has been shown to be the most efficient at low magnetic fields . Recently, a more simplified approach has been investigated, that takes in to account non‐linear and chemical and physical dynamics to produce a master equation to provide insight in to the SABRE mechanism …”