Symmetry constraints on spin dynamics: Application to hyperpolarized NMR

Levitt, Malcolm H.

doi:10.1016/j.jmr.2015.08.021

Cited by 55 publications

(51 citation statements)

References 46 publications

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“…Different behavior is observed for V, where its high‐field T LLS is just 23 s, but its low‐field value is 255 s. Related SABRE‐LLS spectra are shown in Figure 3 c–e. In general, we achieve magnetization to singlet conversion of about 66 % in agreement with theoretical estimates 28. Figure 4 shows the decay of the SABRE‐LLS states as a function of low‐field storage time ( T S ) for substrates II – VI .…”

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confidence: 86%

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A Hyperpolarizable ¹H Magnetic Resonance Probe for Signal Detection 15 Minutes after Spin Polarization Storage

et al. 2016

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Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) are two extremely important techniques with applications ranging from molecular structure determination to human imaging. However, in many cases the applicability of NMR and MRI are limited by inherently poor sensitivity and insufficient nuclear spin lifetime. Here we demonstrate a cost‐efficient and fast technique that tackles both issues simultaneously. We use the signal amplification by reversible exchange (SABRE) technique to hyperpolarize the target 1H nuclei and store this polarization in long‐lived singlet (LLS) form after suitable radiofrequency (rf) pulses. Compared to the normal scenario, we achieve three orders of signal enhancement and one order of lifetime extension, leading to 1H NMR signal detection 15 minutes after the creation of the detected states. The creation of such hyperpolarized long‐lived polarization reflects an important step forward in the pipeline to see such agents used as clinical probes of disease.

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confidence: 86%

“…The choice of spin system is critical in developing a very long lifetime28 and providing access to hyperpolarization by SABRE. Here, we use the pyridazine derivatives of Figure 1.…”

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confidence: 99%

A Hyperpolarizable ¹H Magnetic Resonance Probe for Signal Detection 15 Minutes after Spin Polarization Storage

et al. 2016

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“…34 %) obtained for metronidazole with an atural abundance of 15 N( < 0.3 %) under similar conditions (Figure 3a). [34,35,45,46] The second contributingf actor is access to fresh pH 2 ,w hich can be 15 Ns itesata pprox. It has been shown previously that polarization transfer in such three-spin systemsm ay be more efficient than that in four-spin systems.…”

Section: Spin-relayed Polarization Transfermentioning

confidence: 99%

Hyperpolarizing Concentrated Metronidazole ¹⁵NO₂ Group over Six Chemical Bonds with More than 15 % Polarization and a 20 Minute Lifetime

Shchepin

Birchall

Чуканов

et al. 2019

Chemistry A European J

118

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The NMR hyperpolarization of uniformly 15 N-labeled [ 15 N 3 ]metronidazole is demonstrated by using SABRE-SHEATH. In this antibiotic, the 15 NO 2 group is hyperpolarized throughs pin relays createdb y 15 Ns pins in [ 15 N 3 ]metronidazole, and the polarization is transferred from parahydrogen-derivedh ydrides over six chemical bonds. In less than am inute of parahydrogen bubbling at approximately 0.4 mT, ah igh level of nuclear spin polarization( P 15N ) of around 16 %i sa chieved on all three 15 Ns ites. This prod-uct of 15 Np olarization andc oncentration of 15 Ns pins is arounds ix-fold bettert han any previous value determined for 15 NS ABRE-derived hyperpolarization. At 1.4 T, the hyperpolarized state persists fort ens of minutes (relaxation time, T 1 %10 min). An ovel synthesis of uniformly 15 N-enriched metronidazole is reported with ay ield of 15 %. This approachc an potentially be used for synthesis of aw ide variety of in vivom etabolic probesw ith potentialu ses ranging from hypoxiasensing to theranostic imaging.[a] Prof.

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“…The maximum amplitude of the singlet-filtered 1 H NMR signal, relative to that induced by a single 90 • pulse, was found to be 0.28. The loss relative to the theoretical maximum of 2/3 [37] is not yet fully understood but is attributed to radiofrequency field imperfections and relaxation.…”

Section: Methodsmentioning

confidence: 99%

Long-lived nuclear spin states in rapidly rotating CH 2 D groups

Elliott

Brown

Dumez

et al. 2016

Journal of Magnetic Resonance

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Although monodeuterated methyl groups support proton long-lived states, hindering of the methyl rotation limits the singlet relaxation time. We demonstrate an experimental case in which the rapid rotation of the CH 2 D group extends the singlet lifetime but does not quench the chemical shift difference between the CH 2 D protons, induced by the chiral environment. Proton singlet order is accessed using Spin-Lock Induced Crossing (SLIC) experiments, showing that the singlet relaxation time T S is over 2 minutes, exceeding the longitudinal relaxation time T 1 by a factor of more than 10. This result shows that proton singlet states may be accessible and long-lived in rapidly rotating CH 2 D groups.

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Symmetry constraints on spin dynamics: Application to hyperpolarized NMR

Cited by 55 publications

References 46 publications

A Hyperpolarizable ¹H Magnetic Resonance Probe for Signal Detection 15 Minutes after Spin Polarization Storage

A Hyperpolarizable ¹H Magnetic Resonance Probe for Signal Detection 15 Minutes after Spin Polarization Storage

Hyperpolarizing Concentrated Metronidazole ¹⁵NO₂ Group over Six Chemical Bonds with More than 15 % Polarization and a 20 Minute Lifetime

Long-lived nuclear spin states in rapidly rotating CH 2 D groups

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Symmetry constraints on spin dynamics: Application to hyperpolarized NMR

Cited by 55 publications

References 46 publications

A Hyperpolarizable 1H Magnetic Resonance Probe for Signal Detection 15 Minutes after Spin Polarization Storage

A Hyperpolarizable 1H Magnetic Resonance Probe for Signal Detection 15 Minutes after Spin Polarization Storage

Hyperpolarizing Concentrated Metronidazole 15NO2 Group over Six Chemical Bonds with More than 15 % Polarization and a 20 Minute Lifetime

Long-lived nuclear spin states in rapidly rotating CH 2 D groups

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A Hyperpolarizable ¹H Magnetic Resonance Probe for Signal Detection 15 Minutes after Spin Polarization Storage

A Hyperpolarizable ¹H Magnetic Resonance Probe for Signal Detection 15 Minutes after Spin Polarization Storage

Hyperpolarizing Concentrated Metronidazole ¹⁵NO₂ Group over Six Chemical Bonds with More than 15 % Polarization and a 20 Minute Lifetime