Pith. sign in

REVIEW 3 major objections 4 minor 50 references

SABRE Hyperpolarization of Unmodified Amino Acids in Partially Aqueous Media: L-[1-13C]-Valine as a Model System

T0 review · 3 major / 4 minor · reviewed 2026-08-14 · deepseek-v4-flash

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗ Review JSON

Pith's one-line read SABRE hyperpolarizes unmodified valine in partially aqueous media

desk verdict A credible but under-evidenced proof-of-concept for SABRE of unmodified 13C-valine in wet solvent; the structural identity of the hyperpolarized species needs to be nailed down before the headline claim is fully earned. read the letter →

arxiv 2608.10044 v1 pith:XQL6RAUZ submitted 2026-08-10 physics.chem-ph

Oksana A. Bondar , Thomas B. R. Robertson This is my paper · ORCID
classification physics.chem-ph
keywords SABREparahydrogenhyperpolarization13CNMRspectroscopyaminoacidsvalinebenchtopaqueoussolventsystems
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

This paper aims to establish that Signal Amplification by Reversible Exchange (SABRE) can hyperpolarize unmodified amino acids in solvent systems that contain water, opening a route to label-free, cryogen-free metabolic NMR. Using L-[1-13C]-valine as the model, the authors bubble 92% parahydrogen through an acetone-d6/D2O solution of the amino acid and an iridium–IMes precatalyst at room temperature and observe two hyperpolarized 13C resonances near 190 and 186 ppm, downfield of the free-valine carboxyl signal at about 175 ppm, with apparent enhancements exceeding 60-fold on a 1.1 T benchtop spectrometer. They also report preliminary evidence that L-[1-13C]-glycine behaves similarly. The importance, if the claim holds, is that biologically relevant zwitterionic amino acids can be polarized directly by reversible exchange, without chemical derivatization or a dissolution step.

What carries the argument

The central mechanism is reversible exchange on an iridium–NHC catalyst. The precatalyst [Ir(IMes)(COD)Cl], where IMes is 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene, is activated by parahydrogen, and both parahydrogen and the amino acid bind transiently to the metal; scalar J-couplings in the transient complex transfer the singlet spin order of parahydrogen into 13C magnetization of the carboxyl carbon. The two hyperpolarized resonances at approximately 190 and 186 ppm are the observable signature of the catalyst-associated valine environments carrying this polarization, while the acetone-d6/D2O solvent composition, bubbling time, and substrate-to-catalyst ratio are the dials that tune polarization build-up against relaxation and catalyst deactivation.

What would settle it

Whether the 190/186 ppm signals are SABRE or PHIP can be settled by running the same experiment with a control sample containing no iridium catalyst, and by extracting the organic material after parahydrogen bubbling and checking with high-resolution 13C NMR and mass spectrometry whether intact valine is recovered; if a hydrogenated or decomposed valine species appears, the claim that unmodified valine was hyperpolarized by reversible exchange is falsified.

Watch

Extended reading notes

Core claim

The central claim is that SABRE-mediated 13C hyperpolarization works for an unmodified amino acid in a partially aqueous solvent at room temperature. In the authors' interpretation, the two hyperpolarized resonances at approximately 190 and 186 ppm belong to catalyst-associated valine species whose carboxyl 13C has been polarized during transient coordination to the iridium center, while the free-valine resonance at approximately 175 ppm is not detectably enhanced in the valine case; for glycine, by contrast, both a catalyst-associated resonance near 185 ppm and the free-glycine resonance near 171 ppm appear hyperpolarized. Signal enhancement grows with parahydrogen bubbling time up to a maximum at roughly 20–40 s, depending on the substrate-to-catalyst ratio, and then decreases; more aqueous solvent mixtures yield lower enhancement, and the substrate-to-catalyst ratio systematically changes the apparent enhancement. The paper presents the result as a proof-of-concept that SABRE can be extended to zwitterionic amino acids without derivatization.

Load-bearing premise

The load-bearing premise is that the two hyperpolarized 13C resonances at roughly 190 and 186 ppm arise from intact L-[1-13C]-valine reversibly bound to the iridium catalyst, and not from a hydrogenated, decomposed, or derivatized species that also carries the label; the paper itself states in Section 2.1 that the data do not yet permit definitive structural assignment of these catalyst-associated species.

Editorial extensions

If this is right

  • Unmodified amino acids can be hyperpolarized by SABRE, so amino-acid metabolic NMR no longer requires chemical derivatization or a dissolution step.
  • SABRE functions in partially aqueous media, moving the technique closer to biologically compatible sample conditions.
  • Enhancement is maximized at an intermediate bubbling time (about 20 s at [Val]/[Cat] = 9:1 and about 40 s at 6:1) and declines with longer bubbling, consistent with relaxation and catalyst deactivation.
  • Increasing water content reduces but does not eliminate SABRE enhancement, with detectable polarization still obtained at acetone:D2O = 2:1.
  • Preliminary glycine data suggest the approach extends to other amino acids, with different substrates showing different coordination and exchange behavior.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • Inference: If the catalyst-bound species are intact valine, the same protocol should extend to other 13C-carboxyl-labeled amino acids and small metabolites; the practical bottleneck will be designing water-tolerant ligands that bind zwitterionic substrates without deactivating.
  • Inference: The reported enhancements are referenced to the thermal signal of free valine rather than to the hyperpolarized bound species, so the true polarization gain of the bound complex may be substantially larger than the reported 60-fold value.
  • Inference: The identity of the 190/186 ppm species is the key open question; 2D NMR, 15N labeling, or comparison with independently synthesized iridium–valine complexes would directly distinguish SABRE of valine from parahydrogen-induced hydrogenation or catalyst fragmentation.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 4 minor

Summary. The manuscript reports an experimental study of SABRE hyperpolarization of unmodified L-[1-13C]-valine in partially aqueous acetone-d6/D2O solvent, detected on a 1.1 T benchtop NMR spectrometer. The authors observe two hyperpolarized 13C resonances at approximately 190 and 186 ppm in addition to the thermal free-valine resonance at approximately 175 ppm, and they report apparent signal enhancements of up to about 60-fold. The dependence of the enhancement on parahydrogen bubbling time, solvent composition, and substrate-to-catalyst ratio is investigated, and preliminary data for L-[1-13C]glycine are presented. The authors explicitly acknowledge that the hyperpolarized resonances have no observable thermal counterparts, that the enhancement metric is referenced to the free amino acid resonance, and that the data do not permit definitive structural assignment of the catalyst-associated species.

Significance. If the central claim is correct, this work would be a significant methodological advance: it would show that SABRE can deliver 13C hyperpolarization to underivatized zwitterionic amino acids, opening a route to label-free metabolic NMR studies without chemical derivatization. The paper has notable strengths: the parameter dependence study is systematic, replicate measurements with error bars are reported, the authors are transparent about the approximate nature of the enhancement metric, and the glycine extension gives preliminary evidence of generality. However, the headline claim depends on two load-bearing points that are not yet established: the chemical identity of the hyperpolarized species and the meaning of the reported enhancement factors. Both are explicitly acknowledged as limitations in the manuscript, but they directly affect the interpretation of every quantitative result.

major comments (3)
  1. [Section 2.1, Figs. 2 and 14 (main text and ESI)] The central claim that unmodified L-[1-13C]valine undergoes reversible SABRE rests on the assignment of the hyperpolarized resonances at ~190 and ~186 ppm to catalyst-associated valine species. The authors state that 'the present data do not permit definitive structural assignment of these catalyst-associated species,' and the ESI caption to Fig. 14 disclaims any definitive structural assignment. Because the 13C label is the only enriched site, any species containing that carbon—including condensation products with acetone-d6, hydrogenated COD-derived ligands, or catalyst-decomposition adducts—would produce the same observation. Without mass spectrometry, 2D NMR, isotope-editing, or a post-experiment recovery and identity check on the substrate, the observation does not establish that the hyperpolarized species is intact valine, and hence does not yet support the headline claim of SABRE of unmodified amino acids. This is a load-bearing gap, not a cosmetic caveat.
  2. [Section 2.2 and ESI, Eq. (1)] The reported enhancement factors are apparent values, not polarization gains. SE is defined as Shyp/Stherm, with Stherm taken from the thermal resonance of free valine at ~175 ppm because no thermal counterparts of the ~190 and ~186 ppm resonances are observable. The 'up to approximately 60-fold' statement in the Abstract and Conclusions and the values in Table 1 therefore compare different chemical species; they cannot be read as the polarization level of the hyperpolarized species. The authors do acknowledge this in Section 2.2 and the ESI, but the Abstract and Conclusions restate the unqualified number. The manuscript should rephrase the headline as an apparent enhancement, or report a defensible lower bound based on the thermal detection limit at 190/186 ppm, and the Abstract and Conclusions should carry the same qualification.
  3. [ESI Tables 2 and 3] The individual replicate data do not agree with the summary means in Table 1, and the two tables appear to be interchanged. For example, the seven values in Table 3 at 20 s (46, 61, 56, 52, 58, 112, 45) average 61.4, which is the value Table 1 reports for the ~190 ppm resonance, while the seven values in Table 2 at 20 s average 27.6, matching the ~186 ppm column. Since Table 1 is the basis for the bubbling-time dependence claim, the ESI tables need to be corrected and re-checked before the quantitative conclusions can be relied on.
minor comments (4)
  1. [Fig. 1] The figure labeled 'Graphical picture of L-[1-13C]-Valine' is not an informative structural figure; replace it with a clear chemical structure with the 13C position indicated.
  2. [Fig. 2 caption] The caption reports SE≈128 for the primary resonance and SE≈56 for the secondary resonance, which is inconsistent with the 'up to approximately 60-fold' statement in the Abstract and with the maximum values in Table 1; please reconcile the values or state the different conditions under which they were obtained.
  3. [Section 4 (Materials and Methods)] The sample preparation is described as performed under ambient conditions, but SABRE experiments typically require deoxygenation; please state whether degassing was performed and how oxygen was excluded from the sealed NMR tubes.
  4. [References] Reference 15 is cited as evidence that unmodified α-amino acids can participate in parahydrogen-based hyperpolarization; the text should clarify what was demonstrated there and how it relates to the present claim.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the paper's measured enhancement ratios are direct experimental readouts, not outputs of a fitted model or self-referential derivation.

full rationale

This is an experimental measurement paper. The reported signal enhancements are ratios of integrated NMR intensities (SE = S_hyp/S_therm, Eq. 1 in the ESI), with no parameter fitted to data and no model whose conclusion is built into its inputs. The central claim, that L-[1-13C]valine shows SABRE-type 13C enhancement in partially aqueous solvent, rests on observed spectra rather than on a derivation. The authors explicitly concede that the hyperpolarized resonances at ~190 and ~186 ppm do not have observable thermal counterparts, that the enhancements are therefore 'approximate estimates,' and that 'the present data do not permit definitive structural assignment of these catalyst-associated species.' These are validity or interpretation caveats, not circular reasoning: an unassigned species could undermine the interpretation, but the enhancement measurement itself is not made true by definition. The few self-citations (refs 17, 21, 23) are used for context ('consistent with previous reports' and 'agrees with our previous observations') and are not load-bearing for the experimental result. No step was found where a prediction reduces by construction to an input, where a fitted parameter is renamed as a prediction, or where a uniqueness claim is imported from the authors' own prior work. Accordingly, the appropriate circularity score is 0.

Assumptions & free parameters 0 free parameters · 3 assumptions · 0 invented entities

The paper fits no free parameters; it reports measured NMR integrals. The central assumptions are that the Ir precatalyst activates in situ, that the hyperpolarized resonances are intact labeled valine on the catalyst, and that the free-valine thermal signal is a valid reference for apparent enhancement. None of these is independently verified in the paper, but the first two are standard domain assumptions in SABRE experiments and the third is explicitly disclosed as approximate.

assumptions (3)
  • domain assumption The precatalyst [Ir(IMes)(COD)Cl] forms the active SABRE catalyst in acetone:D2O under parahydrogen bubbling without separate activation or characterization.
    Section 4 describes direct use of the precatalyst synthesized per literature; SABRE activity is inferred from observed hyperpolarization, not from catalyst characterization.
  • domain assumption The hyperpolarized resonances at approximately 190 and 186 ppm correspond to 13C-labeled valine species interacting with the catalyst, not to hydrogenation or decomposition products.
    Section 2.1 assigns these resonances based on the exclusive C1 label and downfield shift, but states 'the present data do not permit definitive structural assignment'.
  • ad hoc to paper The thermal resonance of free valine at approximately 175 ppm is an acceptable reference for computing apparent enhancement of hyperpolarized resonances at other chemical shifts.
    ESI methods use the free amino acid thermal signal when the hyperpolarized species has no observable thermal counterpart; this is a convenience for comparing conditions, not a measurement of that species' polarization gain.

how reviews work

0 comments
Cite this review

Pith. "Pith review of SABRE Hyperpolarization of Unmodified Amino Acids in Partially Aqueous Media: L-[1-13C]-Valine as a Model System." pith.science (2026). https://pith.science/paper/XQL6RAUZ

@misc{pith2026260810044,
  author       = {Pith},
  title        = {Pith review of: SABRE Hyperpolarization of Unmodified Amino Acids in Partially Aqueous Media: L-[1-13C]-Valine as a Model System},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/XQL6RAUZ}},
  note         = {Machine review of arXiv:2608.10044}
}
read the original abstract

Hyperpolarization techniques enhance the sensitivity of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI), enabling detection of low concentration metabolites and dynamic processes. Signal Amplification by Reversible Exchange (SABRE) transfers spin polarization from parahydrogen without permanent chemical modification of the substrate. Here, we demonstrate SABRE-mediated 13C hyperpolarization of unmodified amino acids using L-[1- 13C]-valine as the primary model system and provide preliminary evidence of applicability to glycine. Signal enhancements exceeding 60-fold were observed on a 1.1 T benchtop NMR spectrometer. The dependence of polarization on parahydrogen bubbling time, solvent composition, and substrate-to-catalyst ratio was investigated.

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

50 extracted references · 45 canonical work pages

  1. [1]

    Abernethy and Gareth M

    Colin D. Abernethy and Gareth M. Codd and Mark D. Spicer and Michelle K. Taylor , title =. 2003 , volume =

    2003

  2. [2]

    The Journal of Physical Chemistry B , volume=

    Challenges and advances in the application of dynamic nuclear polarization to liquid-state NMR spectroscopy , author=. The Journal of Physical Chemistry B , volume=. 2021 , publisher=

    work page 2021

  3. [3]

    Nature communications , volume=

    Scalable dissolution-dynamic nuclear polarization with rapid transfer of a polarized solid , author=. Nature communications , volume=. 2019 , publisher=

    work page 2019

  4. [4]

    Angewandte Chemie International Edition , volume=

    Facing and overcoming sensitivity challenges in biomolecular NMR spectroscopy , author=. Angewandte Chemie International Edition , volume=. 2015 , publisher=

    work page 2015

  5. [5]

    Review of Scientific Instruments , volume =

    Tayler, Michael CD and Theis, Thomas and Sjolander, Tobias F and Blanchard, John W and Kentner, Arne and Pustelny, Szymon and Pines, Alexander and Budker, Dmitry , title =. Review of Scientific Instruments , volume =. 2017 , publisher=

    work page 2017

  6. [6]

    European Journal of Inorganic Chemistry , volume=

    Computational (DFT) and Experimental (NMR) Study of the Chelation of an Iridium Hyperpolarization Transfer Catalyst by Amino Acids , author=. European Journal of Inorganic Chemistry , volume=. 2023 , publisher=

    work page 2023

  7. [7]

    Physical Chemistry Chemical Physics , volume=

    Para-hydrogen induced polarization of amino acids, peptides and deuterium--hydrogen gas , author=. Physical Chemistry Chemical Physics , volume=. 2011 , publisher=

    work page 2011

  8. [8]

    Chemical Communications , volume=

    Late-stage deuteration of 13 C-enriched substrates for T 1 prolongation in hyperpolarized 13 C MRI , author=. Chemical Communications , volume=. 2018 , publisher=

    work page 2018

Show all 50 references
  1. [9]

    The Journal of Physical Chemistry C , volume=

    Aqueous NMR signal enhancement by reversible exchange in a single step using water-soluble catalysts , author=. The Journal of Physical Chemistry C , volume=. 2016 , publisher=

    2016

  2. [10]

    Dalton transactions , volume=

    Utilisation of water soluble iridium catalysts for signal amplification by reversible exchange , author=. Dalton transactions , volume=. 2015 , publisher=

    2015

  3. [11]

    Arduengo, III, Anthony J. and H. V. Rasika Dias and Richard L. Harlow and Michael Kline , title =. 1992 , volume =

    1992

  4. [12]

    and Siegfried F

    Arduengo, III, Anthony J. and Siegfried F. Gamper and Joseph C. Calabrese and Fredric Davidson , title =. 1994 , volume =

    1994

  5. [13]

    and Zuccaccia, Daniele and Kovacevic, Anes and Chianese, Anthony R

    Appelhans, Leah N. and Zuccaccia, Daniele and Kovacevic, Anes and Chianese, Anthony R. and Miecznikowski, John R. and Macchioni, Aleco and Clot, Eric and Eisenstein, Odile and Crabtree, Robert H. , title =. 2005 , volume =

    2005

  6. [14]

    Angel Abarca and Pilar G\'omez-Sal and Avelino Mart\'in and Miguel Mena and Josep Mar\'ia Poblet and Carlos Y\'elamos , title =. Inorg. Chem. , year =

  7. [15]

    Proceedings of the National Academy of Sciences , volume=

    Increase in signal-to-noise ratio of> 10,000 times in liquid-state NMR , author=. Proceedings of the National Academy of Sciences , volume=. 2003 , publisher=

    2003

  8. [16]

    Metabolic imaging of patients with prostate cancer using hyperpolarized [1-13C] pyruvate , author=

    Larson; Harzstark, Andrea L.; Marcus, Ferrone; Mark van, Criekinge, et al. Metabolic imaging of patients with prostate cancer using hyperpolarized [1-13C] pyruvate , author=. Science translational medicine , volume=

  9. [17]

    Frontiers in neuroenergetics , volume=

    13C NMR spectroscopy applications to brain energy metabolism , author=. Frontiers in neuroenergetics , volume=. 2013 , publisher=

    2013

  10. [18]

    Neoplasia , volume=

    Hyperpolarized 13C MRI: path to clinical translation in oncology , author=. Neoplasia , volume=. 2019 , publisher=

    2019

  11. [19]

    Frontiers in Bioscience-Landmark , volume=

    The warburg effect: Is it always an enemy? , author=. Frontiers in Bioscience-Landmark , volume=. 2024 , publisher=

    2024

  12. [20]

    Science , volume=

    Reversible interactions with para-hydrogen enhance NMR sensitivity by polarization transfer , author=. Science , volume=. 2009 , publisher=

    2009

  13. [21]

    Accounts of chemical research , volume=

    Application of para hydrogen induced polarization techniques in NMR spectroscopy and imaging , author=. Accounts of chemical research , volume=. 2012 , publisher=

    2012

  14. [22]

    Nature communications , volume=

    Zero-field nuclear magnetic resonance of chemically exchanging systems , author=. Nature communications , volume=. 2019 , publisher=

    2019

  15. [23]

    book Physical Principles of Chirality in NMR, Chapter 10 , volume=

    Hyperpolarization Methods and Their Applications for the Investigation and Discrimination of Enantiomers in NMR , author=. book Physical Principles of Chirality in NMR, Chapter 10 , volume=. 2024 , publisher=

    2024

  16. [24]

    Analytical Chemistry , volume=

    Enzymatic reactions observed with zero-and low-field nuclear magnetic resonance , author=. Analytical Chemistry , volume=. 2023 , publisher=

    2023

  17. [25]

    Journal of the American Chemical Society , volume=

    Microtesla SABRE enables 10\ author=. Journal of the American Chemical Society , volume=. 2015 , publisher=

    2015

  18. [26]

    Analytical Chemistry , volume=

    Zero-to ultralow-field NMR spectroscopy of small biomolecules , author=. Analytical Chemistry , volume=. 2021 , publisher=

    2021

  19. [27]

    Chemical science , volume=

    Hyperpolarization of amino acid derivatives in water for biological applications , author=. Chemical science , volume=. 2015 , publisher=

    2015

  20. [28]

    Chemistry--A European Journal , volume=

    Hyperpolarization of amino acids in water utilizing parahydrogen on a rhodium nanocatalyst , author=. Chemistry--A European Journal , volume=. 2019 , publisher=

    2019

  21. [29]

    Angewandte Chemie , volume=

    Parahydrogen hyperpolarization allows direct NMR detection of -amino acids in complex (bio) mixtures , author=. Angewandte Chemie , volume=. 2021 , publisher=

    2021

  22. [30]

    Angewandte Chemie International Edition , volume=

    Parahydrogen-Induced Polarization of Amino Acids , author=. Angewandte Chemie International Edition , volume=. 2021 , publisher=

    2021

  23. [31]

    Chemical communications , volume=

    Hyperpolarization of amino acid precursors to neurotransmitters with parahydrogen induced polarization , author=. Chemical communications , volume=. 2013 , publisher=

    2013

  24. [32]

    Bengs, Christian and Dagys, Laurynas and Moustafa, Gamal A. I. and Whipham, James W. and Sabba, Mohamed and Kiryutin, Alexey S. and Ivanov, Konstantin L. and Levitt, Malcolm H. , title =. The Journal of Chemical Physics , year =

  25. [33]

    Analyst , volume=

    Hyperpolarised [2-13 C]-pyruvate by 13 C SABRE in an acetone/water mixture , author=. Analyst , volume=. 2024 , publisher=

    2024

  26. [34]

    Molecular Imaging and Biology , volume=

    New horizons in hyperpolarized 13C MRI , author=. Molecular Imaging and Biology , volume=. 2024 , publisher=

    2024

  27. [35]

    Catalysis Today , volume=

    Effect of the hydrogenation solvent in the PHIP-SAH hyperpolarization of [1-13C] pyruvate , author=. Catalysis Today , volume=. 2022 , publisher=

    2022

  28. [36]

    Scientific reports , volume=

    In vivo detection of -glutamyl-transferase up-regulation in glioma using hyperpolarized -glutamyl-[1-13C] glycine , author=. Scientific reports , volume=. 2020 , publisher=

    2020

  29. [37]

    ChemMedChem , volume=

    Improving the Catalyst Efficiency for Hyperpolarization of Pyruvate Derivatives by Means of Hydrogenative PHIP , author=. ChemMedChem , volume=. 2025 , publisher=

    2025

  30. [38]

    Frontiers in oncology , volume=

    In-vitro NMR studies of prostate tumor cell metabolism by means of hyperpolarized [1-13C] pyruvate obtained using the PHIP-sah method , author=. Frontiers in oncology , volume=. 2020 , publisher=

    2020

  31. [39]

    Biol Sex Differ 11 (1): 17 , author=

    Sex differences in cancer mechanisms. Biol Sex Differ 11 (1): 17 , author=

  32. [40]

    The journal of physical chemistry letters , volume=

    Zero-field NMR of Urea: Spin-topology engineering by chemical exchange , author=. The journal of physical chemistry letters , volume=. 2021 , publisher=

    2021

  33. [41]

    Physics of the Dark Universe , volume=

    Characterization of the global network of optical magnetometers to search for exotic physics (GNOME) , author=. Physics of the Dark Universe , volume=. 2018 , publisher=

    2018

  34. [42]

    Communications Chemistry , volume=

    Detection of pyridine derivatives by SABRE hyperpolarization at zero field , author=. Communications Chemistry , volume=. 2023 , publisher=

    2023

  35. [43]

    Chemical Science , volume=

    Using coligands to gain mechanistic insight into iridium complexes hyperpolarized with para-hydrogen , author=. Chemical Science , volume=. 2019 , publisher=

    2019

  36. [44]

    Chemical Communications , volume=

    Rational ligand choice extends the SABRE substrate scope , author=. Chemical Communications , volume=. 2020 , publisher=

    2020

  37. [45]

    Magnetic Resonance in Chemistry , volume=

    Probing signal amplification by reversible exchange using an NMR flow system , author=. Magnetic Resonance in Chemistry , volume=. 2014 , publisher=

    2014

  38. [46]

    Progress in Nuclear Magnetic Resonance Spectroscopy , volume=

    SABRE: Chemical kinetics and spin dynamics of the formation of hyperpolarization , author=. Progress in Nuclear Magnetic Resonance Spectroscopy , volume=. 2019 , publisher=

    2019

  39. [47]

    Angewandte Chemie International Edition , pages=

    Scalable Hyperpolarized MRI Enabled by Ace-SABRE of [1-13C] Pyruvate , author=. Angewandte Chemie International Edition , pages=. 2025 , publisher=

    2025

  40. [48]

    and Mayne, Orry J

    Gater, Callum A. and Mayne, Orry J. and Collins, Benjamin G. and Evans, Kieren J. and Storr, Eleanor M. E. and Whitwood, Adrian C. and Watts, Daniel P. and Tickner, Ben J. and Duckett, Simon B. , title =. The Journal of Physical Chemistry Letters , volume =. 2025 , doi =

    2025

  41. [49]

    JACS Au , volume =

    Min, Sein and Baek, Juhee and Kim, Jisu and Jeong, Hye Jin and Chung, Jean and Jeong, Keunhong , title =. JACS Au , volume =. 2023 , doi =

    2023

  42. [50]

    and Gibard, C

    Fekete, M. and Gibard, C. and Dear, G. J. and Green, G. G. R. and Hooper, A. J. J. and Roberts, A. D. and Cisnetti, F. and Duckett, S. B. Utilisation of water soluble iridium catalysts for signal amplification by reversible exchange. Dalton Trans. 2015. doi:10.1039/C5DT00311C

    2015 doi

Pith tools

Reviewed August 14, 2026 · model on record in the stance chip above.