Thesis prize for Simon OLLIVIER

Each year, the SFSM awards a prize to a young researcher for his or her thesis work. The prize is worth 1250 euros and the winner is invited to present his/her work at the annual congress.

The SFSM 2023 Thesis Prize is awarded to Simon Ollivier for his work on the characterisation of carbohydrates using high-resolution ion mobility spectrometry and mass spectrometry. This work was carried out at the University of Nantes, under the supervision of Hélène Rogniaux and David Ropartz (INRAE, UR Biopolymers, Interactions and Assemblies).

Summary of work:

The inherent complexity of carbohydrates remains a challenge for analytical sciences. No method is currently capable of completely resolving the various isomers present in carbohydrates, despite the fact that these are decisive structural characteristics. Mass spectrometry (MS) alone is blind to many cases of isomerism, and therefore gives incomplete information. Over the last ten years, the coupling of ion mobility spectrometry (IMS) with MS has grown steadily. IMS is sensitive to the conformations of molecules in the gas phase and therefore to (stereo)isomerism. In this context, this thesis explores the potential of high-resolution IMS for structural glycosciences.

The new cyclic IMS (cIMS) geometry, which allows fine manipulation of ions in the gas phase, is studied.

Firstly, we demonstrate through a series of studies that cIMS can resolve the various isomers encountered in carbohydrates. On the basis of these results, we then develop ways of characterising the fine structure of oligosaccharides using multi-stage cIMS. These developments include a targeted sequencing strategy and a non-targeted approach to molecular networks informed by IMS. Finally, we are coupling cIMS with steric exclusion chromatography to work directly on polysaccharides of the order of a hundred kilodalton.

Overall, our results underline the potential of high-resolution IM-MS to become a pivotal method in structural glycosciences, and pave the way for the study of larger, even intact, polysaccharide structures.