Friday, July 28, 2017

Thermal annihilation of photo-induced radicals following dynamic nuclear polarization to produce transportable frozen hyperpolarized 13C-substrates


Capozzi, A., et al., Thermal annihilation of photo-induced radicals following dynamic nuclear polarization to produce transportable frozen hyperpolarized 13C-substrates. 2017. 8: p. 15757.


Hyperpolarization via dynamic nuclear polarization (DNP) is pivotal for boosting magnetic resonance imaging (MRI) sensitivity and dissolution DNP can be used to perform in vivo real-time 13C MRI. The type of applications is however limited by the relatively fast decay time of the hyperpolarized spin state together with the constraint of having to polarize the 13C spins in a dedicated apparatus nearby but separated from the MRI magnet. We herein demonstrate that by polarizing 13C with photo-induced radicals, which can be subsequently annihilated using a thermalization process that maintains the sample temperature below its melting point, hyperpolarized 13C-substrates can be extracted from the DNP apparatus in the solid form, while maintaining the enhanced 13C polarization. The melting procedure necessary to transform the frozen solid into an injectable solution containing the hyperpolarized 13C-substrates can therefore be performed ex situ, up to several hours after extraction and storage of the polarized solid.

Wednesday, July 26, 2017

Dynamic nuclear polarization-magnetic resonance imaging at low ESR irradiation frequency for ascorbyl free radicals



Ito, S. and F. Hyodo, Dynamic nuclear polarization-magnetic resonance imaging at low ESR irradiation frequency for ascorbyl free radicals. Scientific Reports, 2016. 6: p. 21407.


Highly water-soluble ubiquinone-0 (CoQ0) reacts with ascorbate monoanion (Asc) to mediate the production of ascorbyl ree radicals (AFR). Using aqueous reaction mixture of CoQ0 and Asc, we obtained positively enhanced dynamic nuclear polarization (DNP)-magnetic resonance (MR) images of the AFR at low frequency (ranging from 515 to 530 MHz) of electron spin resonance (ESR) irradiation. The shape of the determined DNP spectrum was similar to ESR absorption spectra with doublet spectral peaks. The relative locational relationship of spectral peaks in the DNP spectra between the AFR (520 and 525 MHz), 14N-labeled carbamoyl-PROXYL (14N-CmP) (526.5 MHz), and Oxo63 (522 MHz) was different from that in the X-band ESR spectra, but were similar to that in the 300-MHz ESR spectra. The ratio of DNP enhancement to radical concentration for the AFR was higher than those for 14N-CmP, Oxo63, and flavin semiquinone radicals. The spectroscopic DNP properties observed for the AFR were essentially the same as those for AFR mediated by pyrroloquinoline quinone. Moreover, we made a success of in vivo DNP-MR imaging of the CoQ0-mediated AFR which was administered by the subcutaneous and oral injections as an imaging probe.

[NMR] PhD position at the University of Warwick (September 2017 start)



Exploiting Very-Fast Magic-Angle Spinning NMR: Enabling New Applications to Pharmaceutical Chemistry and Life Sciences


A PhD position in The Molecular Analytical Science Centre for Doctoral Training at the University of Warwick is open for start in September 2017. After successfully completing 6 months of MSc modules, you will carry out a research project (further 3.5 years funding) in the Magnetic Resonance Laboratory under the supervision of Steven P. Brown (Physics) and Józef R. Lewandowski (Chemistry). Working together with Bruker, you will use state-of-the-art very-fast magic-angle spinning technologies in projects that develop and apply advanced solid-state NMR pulse sequences to pharmaceuticals and proteins. You should be from the UK or another European Union country. You need to have a first degree in a relevant scientific discipline (e.g., Physics, Chemistry) and be enthusiastic to work on a project that combines experiment with computer simulation and show a keenness to understand the underlying quantum phenomena that enables NMR to be applied to these important application areas.

For further details, please contact Steven Brown (S.P.Brown@warwick.ac.uk) or Jozef Lewandowski (J.R.Lewandowski@warwick.ac.uk)


Steven Brown
Department of Physics
University of Warwick
Coventry CV4 7AL

United Kingdom, EUROPE
Tel: 00 44 24 76574359
Fax: 00 44 24 76150897



Warwick group webpage: http://go.warwick.ac.uk/nmr/
The UK 850 MHz solid-state NMR facility: http://go.warwick.ac.uk/850mhz/

Getting to Millburn House: http://go.warwick.ac.uk/nmr/getting_here

Molecular Analytical Sciences Centre for Doctoral Training: http://www2.warwick.ac.uk/fac/sci/mas

Researcher ID: http://www.researcherid.com/rid/F-8765-2014 ORCID ID: 0000-0003-2069-8496


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Monday, July 24, 2017

Meet Bridge12 at ISMAR 2017 #ISMAR2017 #DNPNMR

Meet Bridge12 at this year's ISMAR conference in Quebec. We are sharing the booth with PhoenixNMR and will showcase our instruments for Overhauser DNP spectroscopy at 9 GHz.

Stop by and learn more about our solutions for high and low-field microwave instrumentation for EPR and DNP spectroscopy.

Friday, July 21, 2017

Dynamic nuclear polarization-magnetic resonance imaging at low ESR irradiation frequency for ascorbyl free radicals

Ito, S. and F. Hyodo, Dynamic nuclear polarization-magnetic resonance imaging at low ESR irradiation frequency for ascorbyl free radicals. Scientific Reports, 2016. 6: p. 21407.


Highly water-soluble ubiquinone-0 (CoQ0) reacts with ascorbate monoanion (Asc) to mediate the production of ascorbyl free radicals (AFR). Using aqueous reaction mixture of CoQ0 and Asc, we obtained positively enhanced dynamic nuclear polarization (DNP)-magnetic resonance (MR) images of the AFR at low frequency (ranging from 515 to 530 MHz) of electron spin resonance (ESR) irradiation. The shape of the determined DNP spectrum was similar to ESR absorption spectra with doublet spectral peaks. The relative locational relationship of spectral peaks in the DNP spectra between the AFR (520 and 525 MHz), 14N-labeled carbamoyl-PROXYL (14N-CmP) (526.5 MHz), and Oxo63 (522 MHz) was different from that in the X-band ESR spectra, but were similar to that in the 300-MHz ESR spectra. The ratio of DNP enhancement to radical concentration for the AFR was higher than those for 14N-CmP, Oxo63, and flavin semiquinone radicals. The spectroscopic DNP properties observed for the AFR were essentially the same as those for AFR mediated by pyrroloquinoline quinone. Moreover, we made a success of in vivo DNP-MR imaging of the CoQ0-mediated AFR which was administered by the subcutaneous and oral injections as an imaging probe.

Wednesday, July 19, 2017

Coherent evolution of parahydrogen induced polarisation using laser pump, NMR probe spectroscopy: Theoretical framework and experimental observation


Halse, M.E., et al., Coherent evolution of parahydrogen induced polarisation using laser pump, NMR probe spectroscopy: Theoretical framework and experimental observation. J Magn Reson, 2017. 278: p. 25-38.


We recently reported a pump-probe method that uses a single laser pulse to introduce parahydrogen (p-H2) into a metal dihydride complex and then follows the time-evolution of the p-H2-derived nuclear spin states by NMR. We present here a theoretical framework to describe the oscillatory behaviour of the resultant hyperpolarised NMR signals using a product operator formalism. We consider the cases where the p-H2-derived protons form part of an AX, AXY, AXYZ or AA'XX' spin system in the product molecule. We use this framework to predict the patterns for 2D pump-probe NMR spectra, where the indirect dimension represents the evolution during the pump-probe delay and the positions of the cross-peaks depend on the difference in chemical shift of the p-H2-derived protons and the difference in their couplings to other nuclei. The evolution of the NMR signals of the p-H2-derived protons, as well as the transfer of hyperpolarisation to other NMR-active nuclei in the product, is described. The theoretical framework is tested experimentally for a set of ruthenium dihydride complexes representing the different spin systems. Theoretical predictions and experimental results agree to within experimental error for all features of the hyperpolarised 1H and 31P pump-probe NMR spectra. Thus we establish the laser pump, NMR probe approach as a robust way to directly observe and quantitatively analyse the coherent evolution of p-H2-derived spin order over micro-to-millisecond timescales.

Tuesday, July 18, 2017

[NMR] Postdoc position on SSNMR at the University of Lille, France #DNPNMR


Please forward to potential candidates.

Project title: Development of high-field (DNP)-NMR methods to detect quadrupolar nuclei on catalytic surfaces

A two-year postdoc position in solid-state NMR spectroscopy of advanced materials is available at the University of Lille, Lille, France. It will start preferably in December 2017.

Project description: The development of improved heterogeneous catalysts can be undertaken in a rational way by a better
understanding of their structures. Solid-state NMR spectroscopy is very well suited to the study of heterogeneous catalysts because it can give information on the local structure. However, the lack of sensitivity and resolution poses limit for the characterization of surface sites, notably when they are occupied by quadrupolar nuclei (11B, 17O, 27Al, 67Zn, 95Mo...) exhibiting NMR signal broaden by large quadrupolar interaction. This project aims at developing and applying novel solid-state high-field (DNP)NMR methods to probe the local environment of quadrupolar nuclei. It will provide unique insights into the structure of the catalytic surfaces, which will be useful to improve their performances.

Host and research infrastructure: Lille is a vibrant and handsome city, imbued with a rich history, located in the center of northwestern Europe (only 30 min by high-speed trains from Brussels, 1h from Paris and 1h30 from London). Lille is one of France’s top student cities and the university of Lille is a leading center for magnetic resonance. Lille NMR facility includes 800 and 900 MHz NMR spectrometers and has been selected to host the first 1.2 GHz NMR spectrometer to be installed in France. Our research group is internationally known for the development of solid-state NMR methods, notably for quadrupolar nuclei, and the characterization of heterogeneous catalysts. We have an expertise in high-field solid-state NMR spectroscopy and were among the pioneers of high-field DNP-NMR of hybrid and inorganic materials. 

The person: We seek application from candidates with experience in the development of solid-state NMR methods and/or the NMR characterization of inorganic materials and catalysts. The successful applicant will be given the opportunity to work in an exciting environment with national and international collaborations.

Contact: Applications and informal queries about the lab and research projects should be directed by

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