Research output: Contribution to journal › Article › peer-review
Efficient conversion of anti-phase spin order of protons into 15N magnetisation using SLIC-SABRE. / Knecht, Stephan; Kiryutin, Alexey S.; Yurkovskaya, Alexandra V. et al.
In: Molecular Physics, Vol. 117, No. 19, 02.10.2019, p. 2762-2771.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Efficient conversion of anti-phase spin order of protons into 15N magnetisation using SLIC-SABRE
AU - Knecht, Stephan
AU - Kiryutin, Alexey S.
AU - Yurkovskaya, Alexandra V.
AU - Ivanov, Konstantin L.
PY - 2019/10/2
Y1 - 2019/10/2
N2 - SABRE (Signal Amplification By Reversible Exchange) is a technique for enhancement of NMR (Nuclear Magnetic Resonance) signals, which utilises parahydrogen (pH 2, the H 2 molecule in its nuclear singlet spin state) as a source of non-thermal spin order. In SABRE experiments, pH 2 binds transiently to an organometallic complex with a to-be-polarised substrate; subsequently, spin order transfer takes place and the substrate acquires non-thermal spin polarisation resulting in strong NMR signal enhancement. In this work, we argue that the spin order of H 2 in SABRE experiments performed at high magnetic fields is not necessarily the singlet order but rather anti-phase polarisation, S1zS2z. Although SABRE exploits pH 2, i.e. the starting spin order of H 2 is supposed to be the singlet order, in solution, S−T 0 conversion becomes efficient once pH 2 binds to a complex. Such a variation of the spin order, which becomes S1zS2z, has an important consequence: NMR methods used for transferring SABRE polarisation need to be modified. Here we demonstrate that methods proposed for the initial singlet order may not work for the S1zS2z order; however, a simple modification makes them efficient again.
AB - SABRE (Signal Amplification By Reversible Exchange) is a technique for enhancement of NMR (Nuclear Magnetic Resonance) signals, which utilises parahydrogen (pH 2, the H 2 molecule in its nuclear singlet spin state) as a source of non-thermal spin order. In SABRE experiments, pH 2 binds transiently to an organometallic complex with a to-be-polarised substrate; subsequently, spin order transfer takes place and the substrate acquires non-thermal spin polarisation resulting in strong NMR signal enhancement. In this work, we argue that the spin order of H 2 in SABRE experiments performed at high magnetic fields is not necessarily the singlet order but rather anti-phase polarisation, S1zS2z. Although SABRE exploits pH 2, i.e. the starting spin order of H 2 is supposed to be the singlet order, in solution, S−T 0 conversion becomes efficient once pH 2 binds to a complex. Such a variation of the spin order, which becomes S1zS2z, has an important consequence: NMR methods used for transferring SABRE polarisation need to be modified. Here we demonstrate that methods proposed for the initial singlet order may not work for the S1zS2z order; however, a simple modification makes them efficient again.
KW - parahydrogen
KW - polarisation transfer
KW - SABRE method
KW - Spin hyperpolarisation
KW - spin order
KW - PARA-HYDROGEN
KW - NMR
KW - KINETICS
KW - HYPERPOLARIZATION
KW - MECHANISMS
KW - PARAHYDROGEN
KW - POLARIZATION TRANSFER
UR - http://www.scopus.com/inward/record.url?scp=85053260706&partnerID=8YFLogxK
U2 - 10.1080/00268976.2018.1515999
DO - 10.1080/00268976.2018.1515999
M3 - Article
AN - SCOPUS:85053260706
VL - 117
SP - 2762
EP - 2771
JO - Molecular Physics
JF - Molecular Physics
SN - 0026-8976
IS - 19
ER -
ID: 16568055