Research output: Contribution to journal › Article › peer-review
Re-polarization of nuclear spins using selective SABRE-INEPT. / Knecht, Stephan; Kiryutin, Alexey S.; Yurkovskaya, Alexandra V. et al.
In: Journal of Magnetic Resonance, Vol. 287, 01.02.2018, p. 10-14.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Re-polarization of nuclear spins using selective SABRE-INEPT
AU - Knecht, Stephan
AU - Kiryutin, Alexey S.
AU - Yurkovskaya, Alexandra V.
AU - Ivanov, Konstantin L.
N1 - Publisher Copyright: © 2017
PY - 2018/2/1
Y1 - 2018/2/1
N2 - A method is proposed for significant improvement of NMR pulse sequences used in high-field SABRE (Signal Amplification By Reversible Exchange) experiments. SABRE makes use of spin order transfer from parahydrogen (pH2, the H2 molecule in its singlet spin state) to a substrate in a transient organometallic Ir-based complex. The technique proposed here utilizes “re-polarization”, i.e., multiple application of an NMR pulse sequence used for spin order transfer. During re-polarization only the form of the substrate, which is bound to the complex, is excited by selective NMR pulses and the resulting polarization is transferred to the free substrate via chemical exchange. Owing to the fact that (i) only a small fraction of the substrate molecules is in the bound form and (ii) spin relaxation of the free substrate is slow, the re-polarization scheme provides greatly improved NMR signal enhancement, ε. For instance, when pyridine is used as a substrate, single use of the SABRE-INEPT sequence provides ε≈260 for 15N nuclei, whereas SABRE-INEPT with re-polarization yields ε>2000. We anticipate that the proposed method is useful for achieving maximal NMR enhancement with spin hyperpolarization techniques.
AB - A method is proposed for significant improvement of NMR pulse sequences used in high-field SABRE (Signal Amplification By Reversible Exchange) experiments. SABRE makes use of spin order transfer from parahydrogen (pH2, the H2 molecule in its singlet spin state) to a substrate in a transient organometallic Ir-based complex. The technique proposed here utilizes “re-polarization”, i.e., multiple application of an NMR pulse sequence used for spin order transfer. During re-polarization only the form of the substrate, which is bound to the complex, is excited by selective NMR pulses and the resulting polarization is transferred to the free substrate via chemical exchange. Owing to the fact that (i) only a small fraction of the substrate molecules is in the bound form and (ii) spin relaxation of the free substrate is slow, the re-polarization scheme provides greatly improved NMR signal enhancement, ε. For instance, when pyridine is used as a substrate, single use of the SABRE-INEPT sequence provides ε≈260 for 15N nuclei, whereas SABRE-INEPT with re-polarization yields ε>2000. We anticipate that the proposed method is useful for achieving maximal NMR enhancement with spin hyperpolarization techniques.
KW - Parahydrogen
KW - Polarization transfer
KW - SABRE
KW - Spin hyperpolarization
KW - PARA-HYDROGEN
KW - NMR-SPECTROSCOPY
KW - MAGNETIZATION
KW - HETERONUCLEI
KW - HIGH-FIELD
KW - REVERSIBLE EXCHANGE
KW - ENHANCEMENT
KW - PARAHYDROGEN-INDUCED POLARIZATION
KW - CROSS-POLARIZATION
KW - HYPERPOLARIZATION
UR - http://www.scopus.com/inward/record.url?scp=85038836082&partnerID=8YFLogxK
U2 - 10.1016/j.jmr.2017.12.010
DO - 10.1016/j.jmr.2017.12.010
M3 - Article
C2 - 29274936
AN - SCOPUS:85038836082
VL - 287
SP - 10
EP - 14
JO - Journal of Magnetic Resonance
JF - Journal of Magnetic Resonance
SN - 1090-7807
ER -
ID: 9164371