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Reference : UMR6230-JEADUM-005
Workplace : NANTES
Date of publication : Monday, March 02, 2020
Scientific Responsible name : Jean-Nicolas Dumez et Patrick Giraudeau
Type of Contract : PhD Student contract / Thesis offer
Contract Period : 36 months
Start date of the thesis : 1 October 2020
Proportion of work : Full time
Remuneration : 2 135,00 € gross monthly
Description of the thesis topic
Diffusion NMR (DOSY) is a powerful tool for the analysis of mixtures. Sometimes called “chromatographic NMR”, the DOSY method makes it possible to separate information on the compounds of a mixture, without a physical separation step. Its field of application ranges from fraud detection for pharmaceutical compounds to the study of mechanisms in organic synthesis. At the CEISAM laboratory, one of the leaders in NMR analysis of mixtures, we are working on the development of ultra-fast DOSY methods, which allow data recording in less than a second, instead of several minutes with conventional methods [1-3]. Through the joint development of new pulse sequences and numerical simulation tools, we have shown that ultrafast NMR based on spatial coding has great potential to provide unique information on out of equilibrium systems. The laboratory has a rare combination of instruments (hyperpolarization, imaging, online monitoring) which opens up new perspectives in the field.
The objective of this project is to develop analytical methods based on diffusion NMR which allow the study of samples which change rapidly over time, and in particular reaction mixtures and hyperpolarized substrates. Hyperpolarization is a revolutionary method which makes it possible to increase the sensitivity of NMR by several orders of magnitude. These developments will thus allow the detection limits of NMR analysis of mixtures, and the time scales that can be studied, to be pushed back by several orders of magnitude. The project is organized in two parts:
• the development of methods allowing optimal sampling of samples which change over time, and in particular of pulse sequences which make it possible to increase the sensitivity and the temporal resolution;
• the implementation of these experiments on mixtures which evolve over time, and in particular catalyzed chemical reactions and hyperpolarized substrates.
These two axes, which involve experiments, numerical simulations and analysis, are interactive, and the Ph.D. student will additionally be involved in team projects oriented towards applications of DOSY NMR, in particular for fraud detection and the study of reaction mechanisms.
The work will be carried out in a stimulating collaborative environment, with many other doctoral students and post-doctoral students recently recruited as part of two ERC projects. The recruited doctoral student will interact more specifically with several doctoral students and post-doctoral students, as well as with several specialists in the development of pulse sequences.
CEISAM is the molecular chemistry laboratory of the University of Nantes and brings together 5 recognized research teams in theoretical, physical and analytical chemistry, and in organic synthesis. The CEISAM laboratory NMR platform is the largest NMR platform in Western France. Its equipment includes 6 high field spectrometers (400 - 700 MHz), 3 low field spectrometers, equipment for MRI and a polarizer for nuclear dynamic polarization. CEISAM is located in the dynamic environment of the city of Nantes, near the Atlantic coast and South Brittany.
1. L. Guduff, I. Kuprov, C. van Heijenoort and J.-N. Dumez, Spatially encoded 2D and 3D diffusion-ordered NMR spectroscopy, Chem. Commun., 53, 701 (2017).
2. L. Guduff, D. Kurzbach, C. van Heijenoort, D. Abergel and J.-N. Dumez, Single-scan 13C diffusion-ordered NMR spectroscopy of DNP-hyperpolarised substrates, Chem. Eur. J. 23, 16722 (2017).
3. L. Guduff, P. Berthault, C. van Heijenoort, J.-N. Dumez and G. Huber, Single-scan diffusion-ordered NMR spectroscopy of SABRE-hyperpolarised mixtures, ChemPhysChem 20, 392 (2019).
The candidate has a background in chemistry (preferably physical or analytical chemistry) or in physics, and an interest in the development of analytical methods through an approach combining theory and experiments. Due to the collaborative and international nature of the project, good communication skills in English are required. The recruited doctoral student will be required to transmit his knowledge to other students (Master, Doctorate) and to present his work at an international congress.
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