Session: Parallel session 2 - Ion mobility spectrometry

Multistage ion mobility MS for innovative bio-based materials conception: towards high throughput sequencing of ramified carbohydrates?

Rania BENAZZA^1,2, Mathieu FANUEL^1,2, Bernard CATHALA¹, Hélène ROGNIAUX^1,2, David ROPARTZ^1,2

¹INRAE, URBIA, F-44316 , Nantes, France
²INRAE, PROBE Research Infrastructure, BIBS Facility, F-44316, Nantes, France

Introduction

Plant based polysaccharides are promising candidates for the conception of bio-based materials due to the variety of their structures, which bring different properties of interest. To understand and improve their benefits for material design, and to promote their use, the structural key points that drive their activity need to be characterized. Cyclic IMS (cIMS), that particularly allows the combination of slicing experiments and multistep fragmentation (multistage IMSn), have proven to be a powerful tool for the structural challenges in glycosciences. Here, we conduct IMSn experiments to unravel the complexity of ramified hemicellulose heteropolymers.

Methodology

Galactomannans and glucomannans oligosaccharides (GMOS) were analysed using a cIMS (Waters, Wilmslow, UK). After their isolation, using the mobility dimension, each conformer was fragmented in the pre-array store to define the arrival time distribution (ATD) profile of (i) constitutive monosaccharide and (ii) disaccharides. IMS2 experiment were performed for the extremities followed by IMS3 for internal sequencing. These ATD profiles were then compared with a home-made database produced from a library of mono- and di-saccharides.

Results & conclusions

Our results show that ATD profiles resulting from the IMSn experiments matched those of the reference standards. This match occurred despite the featuring of several epimers in the same structure and lateral branching, which resulted in an “isomeric” sequencing of heterogeneous GMOS.

Altogether, our results pinpoint that the combination of high-resolution IMS, slicing experiments and multistage fragmentation resolve complex oligosaccharides, offering a detailed structural elucidation. For the first time, this includes the analysis of ramified structures as found in in the majority of hemicelluloses. This approach is expected to streamline bio-based carbohydrates characterization, offering the conception of a larger sustainable polymers’ library.