Using
            <i>para</i>
            hydrogen to hyperpolarize amines, amides, carboxylic acids, alcohols, phosphates, and carbonates

Iali, Wissam; Rayner, Peter J.; Duckett, Simon B.

doi:10.1126/sciadv.aao6250

Cited by 127 publications

(189 citation statements)

References 41 publications

Supporting

Mentioning

173

Contrasting

Unclassified

Order By: Relevance

“…The results are consistent with weak acetate binding to the IrIMes catalyst (fast on the 13 C NMR time scale). 13 C enhancements of up to 108‐fold were observed, which may be compared to recent results of ≈48‐fold and ≈140‐fold achieved in acetate via SABRE‐RELAY and spin‐relay within a cleavable agent, respectively (both at 9.4 T). We anticipate much larger enhancements should be possible by optimizing the experimental conditions of the present approach, particularly with respect to improving the magnetic shield and carefully avoiding relaxation sinks.…”

Section: Resultssupporting

confidence: 61%

“…In summary, it is shown that “direct” hyperpolarization of 13 C spins of 1‐ 13 C‐acetate can be rapidly achieved using SABRE‐SHEATH, without the need for polarization to be relayed via either an exchangeable proton or a spin network within a cleavable substrate . The results are consistent with weak acetate binding to the IrIMes catalyst (fast on the 13 C NMR time scale).…”

Section: Resultsmentioning

confidence: 53%

See 1 more Smart Citation

“Direct” ¹³C Hyperpolarization of ¹³C‐Acetate by MicroTesla NMR Signal Amplification by Reversible Exchange (SABRE)

et al. 2019

View full text Add to dashboard Cite

Herein, we demonstrate “direct” 13C hyperpolarization of 13C‐acetate via signal amplification by reversible exchange (SABRE). The standard SABRE homogeneous catalyst [Ir‐IMes; [IrCl(COD)(IMes)], (IMes=1,3‐bis(2,4,6‐trimethylphenyl), imidazole‐2‐ylidene; COD=cyclooctadiene)] was first activated in the presence of an auxiliary substrate (pyridine) in alcohol. Following addition of sodium 1‐13C‐acetate, parahydrogen bubbling within a microtesla magnetic field (i.e. under conditions of SABRE in shield enables alignment transfer to heteronuclei, SABRE‐SHEATH) resulted in positive enhancements of up to ≈100‐fold in the 13C NMR signal compared to thermal equilibrium at 9.4 T. The present results are consistent with a mechanism of “direct” transfer of spin order from parahydrogen to 13C spins of acetate weakly bound to the catalyst, under conditions of fast exchange with respect to the 13C acetate resonance, but we find that relaxation dynamics at microtesla fields alter the optimal matching from the traditional SABRE‐SHEATH picture. Further development of this approach could lead to new ways to rapidly, cheaply, and simply hyperpolarize a broad range of substrates (e.g. metabolites with carboxyl groups) for various applications, including biomedical NMR and MRI of cellular and in vivo metabolism.

show abstract

Section: Resultssupporting

confidence: 61%

Section: Resultsmentioning

confidence: 53%

“Direct” ¹³C Hyperpolarization of ¹³C‐Acetate by MicroTesla NMR Signal Amplification by Reversible Exchange (SABRE)

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The corresponding decay curve (Figure g) gives a T 1 value of ≈14±9 s at 0.3 T for the combined 13 C signal. This 13 C enhancement may be compared to that reported very recently by Iali et al., (≈48‐fold at 9.4 T), who demonstrated an alternate strategy for hyperpolarizing carboxylic acids by hyperpolarizing the exchangeable 1 H of NH 3 that hydrogen‐exchanges with the substrate in CD 2 Cl 2 . The value calculated here for imidazole 15 N enhancement includes the fact that magnetization achieved on one substrate 15 N spin becomes effectively “diluted” by a factor of two (because the two 15 N spins are magnetically equivalent).…”

Section: Methodssupporting

confidence: 58%

Toward Cleavable Metabolic/pH Sensing “Double Agents” Hyperpolarized by NMR Signal Amplification by Reversible Exchange

Kidd

Mashni

Limbach

et al. 2018

Chemistry A European J

View full text Add to dashboard Cite

We show the simultaneous generation of hyperpolarized C-labeled acetate and N-labeled imidazole following spin-relay of hyperpolarization and hydrolysis of the acetyl moiety on 1- C- N -acetylimidazole. Using SABRE-SHEATH (Signal Amplification by Reversible Exchange in SHield Enables Alignment Transfer to Heteronuclei), transfer of spin order occurs from parahydrogen to acetylimidazole N atoms and the acetyl C site (≈263-fold enhancement), giving rise to relatively long hyperpolarization lifetimes at 0.3 T (T ≈52 s and ≈149 s for C and N, respectively). Immediately following polarization transfer, the C-labeled acetyl group is hydrolytically cleaved to produce hyperpolarized C-acetate/acetic acid (≈140-fold enhancement) and N-imidazole (≈180-fold enhancement), the former with a C T of ≈14 s at 0.3 T. Straightforward synthetic routes, efficient spin-relay of SABRE hyperpolarization, and facile bond cleavage open a door to the cheap and rapid generation of long-lived hyperpolarized states within a wide range of molecular targets, including biologically relevant carboxylic acid derivatives, for metabolic and pH imaging.

show abstract

“…[75] This method begins by using SABRE to hyperpolarize an amine or ammonia, and proton exchanges allow the relay of polarization into the target substrate (Scheme 2). [75] This method begins by using SABRE to hyperpolarize an amine or ammonia, and proton exchanges allow the relay of polarization into the target substrate (Scheme 2).…”

Section: Discussionmentioning

confidence: 99%

Signal Amplification by Reversible Exchange (SABRE): From Discovery to Diagnosis

2018

Self Cite

View full text Add to dashboard Cite

Signal amplification by reversible exchange (SABRE) turns typically weak magnetic resonance responses into strong signals making previously impractical measurements possible. This technique has gained significant popularity because of its speed and simplicity. This Minireview tracks the development of SABRE from the initial hyperpolarization of pyridine in 2009 to the point in which 50 % H polarization levels have been achieved in a di-deuterio-nicotinate, a key step in the pathway to potential clinical use. Simple routes to highly efficient N hyperpolarization and the creation of hyperpolarized long-lived magnetic states are illustrated. To conclude, we describe how the recently reported SABRE-RELAY approach offers a route for parahydrogen to hyperpolarize a much wider array of molecular scaffolds, such as amides, alcohols, carboxylic acids, and phosphates, than was previously thought possible. We predict that collectively these developments ensure that SABRE will significantly impact on both chemical analysis and the diagnosis of disease in the future.

show abstract

Using para hydrogen to hyperpolarize amines, amides, carboxylic acids, alcohols, phosphates, and carbonates

Abstract: Parahydrogen is used to give efficient NMR detection of array of amines, amides, alcohols, carboxylates, carbonates, and phosphates.

Cited by 127 publications

References 41 publications

“Direct” ¹³C Hyperpolarization of ¹³C‐Acetate by MicroTesla NMR Signal Amplification by Reversible Exchange (SABRE)

“Direct” ¹³C Hyperpolarization of ¹³C‐Acetate by MicroTesla NMR Signal Amplification by Reversible Exchange (SABRE)

Toward Cleavable Metabolic/pH Sensing “Double Agents” Hyperpolarized by NMR Signal Amplification by Reversible Exchange

Signal Amplification by Reversible Exchange (SABRE): From Discovery to Diagnosis

Contact Info

Product

Resources

About

Using para hydrogen to hyperpolarize amines, amides, carboxylic acids, alcohols, phosphates, and carbonates

Abstract: Parahydrogen is used to give efficient NMR detection of array of amines, amides, alcohols, carboxylates, carbonates, and phosphates.

Cited by 127 publications

References 41 publications

“Direct” 13C Hyperpolarization of 13C‐Acetate by MicroTesla NMR Signal Amplification by Reversible Exchange (SABRE)

“Direct” 13C Hyperpolarization of 13C‐Acetate by MicroTesla NMR Signal Amplification by Reversible Exchange (SABRE)

Toward Cleavable Metabolic/pH Sensing “Double Agents” Hyperpolarized by NMR Signal Amplification by Reversible Exchange

Signal Amplification by Reversible Exchange (SABRE): From Discovery to Diagnosis

Contact Info

Product

Resources

About

“Direct” ¹³C Hyperpolarization of ¹³C‐Acetate by MicroTesla NMR Signal Amplification by Reversible Exchange (SABRE)

“Direct” ¹³C Hyperpolarization of ¹³C‐Acetate by MicroTesla NMR Signal Amplification by Reversible Exchange (SABRE)