Temperature-induced self-assembly of degalactosylated xyloglucan at low concentration

Abstract

Xyloglucan is a natural polysaccharide having a cellulose-like backbone and hydroxyl groups-rich side-chains. In its native form the polymer is water-soluble and forms gel only in presence of selected co-solutes. When a given fraction of galactosyl residues are removed by enzymatic reaction, the polymer acquires the ability to form a gel in aqueous solution at physiological temperatures, a property of great interest for biomedical/pharmaceutical applications. This work presents data on the effect of a temperature increase on degalactosylated xyloglucan dispersed in water at concentration low enough not to run into macroscopic gelation. Results obtained over a wide interval of length scales show that, on increasing temperature, individual polymer chains and pre-existing clusters self-assemble into larger structures. The process implies a structural rearrangement over a few nanometers scale and an increase of dynamics homogeneity. The relation of these findings to coil-globule transition and phase separation is discussed.

In-situ gelling xyloglucan formulations as 3D artificial niche for adipose stem cell spheroids

“…completely devoid of chain aggregates. This is due to the presence of galactosebare sequences in the chains that cause side-by-side association of few segments of different chains forming condensed domains [45,46]. The dispersions were stored at 4°C.…”

Injectable xyloglucan hydrogels incorporating spheroids of adipose stem cells for bone and cartilage regeneration

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From toroidal to rod‐like nanostructure, a mechanism study for the reversible morphological control on amphiphilic triblock copolymer micelles

“…Water content, nature of solvent, addition of small molecules, and composition of the copolymer are all factors of solution composition, whereas temperature, shearing, UV‐light irradiation, electromagnetic, and so on, are factors of external field . Basically, external controls, typically temperature and shear, are preferred for their easy manipulation, simple instrument, and little interference …”