Interview | Matter ＆ the Universe | Chemistry | Physics
Gaël De Paëpe - Pushing the limits of sensitivity and resolution of the NMR (ULT-MAS-DLP)
NMR techniques evolve and diversify. Here’s the latest on one of its avatars in deep mutation with Gaël de Paepe who, thanks to these techniques, has managed the feat of analysing the membrane of living bacterial cells. With his project ERC, Gaël De Paepe seeks to push the limits of sensitivity and resolution of the NMR.
High-field dynamic nuclear polarization (DNP) is revolutionizing solid-state NMR, a chemical analysis technique known to “provide ultra-rich information on a signal which is very weak” or even too weak to carry out analyses in reasonable times. “We are halfway there,” says de Paepe. “We reduced the duration of an analysis from one year to one day we are hoping to gain three orders of magnitude!”
While DNP experiments have long been limited to a magnetic field below 1 tesla, the recent emergence of commercial spectrometers with a high magnetic field has changed everything. In late 2011, the team from Grenoble acquired the third DNP machine in the world using a magnetic field of 10 tesla. “We are transforming this machine to operate at a temperature of 10 K (-263 °C) instead of 100 K. We just replaced the nitrogen used for cooling by heli, which involved substantial technological changes. We are also developing a new family of polarizing agents that achieve even better performances.” And the scientist sees even further. “Within five years, it will be possible to work below 30 tesla, but we still have lots to decipher! The development of DNP will allow the scientific community to carry out ultra-sensitive NMR experiments at high resolutions that will resolve the atomic structures of complex assemblies or detect nuclei with very low sensitivity, such as calcium or oxygen. “
Gaël De Paëpe (Institute of Nanosciences and Cryogenics - CEA / Université Grenoble Alpes, Grenoble) aims to push the boundaries of sensitivity and resolution of the NMR as part of a project selected by the European Research Council in 2016.