Abstract text: The helicoidal architecture (cholesteric liquid-crystalline organisation) represents one of nature’s most efficient strategies for engineering robust and functional materials. The principle is invariant: each lamella comprises aligned fibrils, and successive lamellas are rotated by a fixed angle. In the primary cell wall, this organisation is based on polysaccharides, specifically cellulose microfibrils. This arrangement results in strong structural anisotropy of individual lamellas, while the wall as a whole is in-plane isotropic. Consequently, it is mechanically stable and highly resistant to in-plane stress. Hemicelluloses theoretically could form cholesteric liquid crystals and provide scaffolding for cellulose fibrils. Their role in helicoidal wall structure, however, remains an open question. Noteworthy, cellulose and glucuronoxylans re-associate into a cholesteric-like structure in vitro, while the removal of glucuronoxylans from the system leads to cellulose flocculation. This suggests an 'anti-flocculant' role for glucuronoxy-lans during assembly. The helicoidal architecture has been confirmed in superficial primary cell walls of Helianthus and Vigna hypocotyls. However, its occurrence in Arabidopsis remains inconclusive. The literature indicates that in giant-celled algae (e.g., Nitella), visualisation of the helicoidal architecture is highly reliant on the application of specific TEM sample preparation protocols. Thus, we test various protocols to reveal the arrangement of polysaccharides in Arabidopsis.