Finalist EPFL doctorate Award 2016 – Aurélien Bornet
© 2016 Aurélien Bornet
Special distinction from the selection committee to Aurélien Bornet for his thesis "De l'usage des protons hyperpolarisés pour augmenter la sensibilité de la RMN". Thesis n°6581 (2015). Thesis directors: Prof. G. Bodenhausen, Dr S. Jannin.
Nuclear Magnetic Resonance (NMR) has become an inescapable technique for spectroscopic identification. Magnetic Resonance Imaging (MRI) is used daily in medical imaging, the technique being safe, remarkably versatile and non-invasive. Nevertheless, many magnetic resonance applications are limited by their intrinsic low sensitivity, arising from the low magnetic energies of the nuclear spins compared to the thermal energies of the molecules.
In 2003, Golman and collaborators accomplished a breakthrough to enhance the NMR signals of carbon-13 by a factor 10’000. The principle of the technique is to transfer the high electron polarization at temperatures close to 1 Kelvin to the nuclear spins and subsequently to dissolve the hyperpolarized solution before transferring it to an NMR spectrometer or a MRI scanner.
The goal of my PhD thesis was to improve the technique by following three axes. The intensity and throughput of the production of hyperpolarized analytes was boosted by the use of Cross-Polarization, transferring to other nuclei the high and rapidly accessible proton DNP polarization. The time interval during which the hyperpolarized magnetization is available was greatly extended using so called Long-Lived States. Finally, new MR methods were developed to use the hyperpolarized magnetization efficiently, in drug screening, metabolic and metabolomics applications.
