Atomic Force Microscopy-related techniques applied to the nanocharacterization of mechanical and chemical properties of plant cell walls and bioinspired polymer films

Lignocellulosic biomass (LB) is a complex network of polymers that constitute plant cell walls (PCWs). It comes from various sources: residues from agriculture and forest or dedicated plants. Since LB is composed of various polymers such as cellulose, hemicellulose (polysaccharides) and lignin (polyphenols), LB transformation can potentially produce chemicals, materials and biofuels in dedicated biorefineries. Consequently, LB exploitation is considered as a way to limit greenhouse gas emission and a sustainable alternative to fossil carbon-derived products. However, the architectural and chemical complexity of LB is also a bottleneck to its costeffective industrial conversion. Today, to achieve this goal, not only the cellulosic part of LB but also the hemicellulosic and lignin parts must be retrieved and the relationships between the structure and the properties of the polymers should be well understood from the macroscopic to the nanoscopic scales. The goal of this talk is to show the potentialities of atomic force microscopy (AFM) in different modes to realize the nanoscale characterization of plant cell walls and of bioinspired polymer films. Thanks to the use of adhesion measurements via tip functionalization with lignocellulosic polymers, of nanoInfrared absorption, nanomechanical and nanothermal measurements, and by comparison between real plant cell walls and lignocellulosic bioinspired films, we will try to understand the relationship between the composition and the supramolecular organization of lignocellulosic polymers and their nanoscale properties.