Journal Article

IMPULSE-2026-00125

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Preferential solvation drives polysaccharide conformation and viscoelasticity

Borah, P. (Corresponding author)MLZ* ; Reid, J. E. S. J. ; MacCalman, T. ; Irani, A. H. ; Russo, D. ; Smiatek, J. ; Hunger, J. ; Sarter, M. ; Dinu, V. ; Natali, F. ; Boehm, M. ; Harding, S. E. ; Williams, M. A. K. ; Baier, S. K. ; Yakubov, G. E. (Corresponding author)

2026
Elsevier Science Amsterdam [u.a.]

Please use a persistent id in citations: doi:10.1016/j.carbpol.2026.125726

Abstract: Polysaccharide conformations are central to biological function but exhibit a strikingly counterintuitive, non-monotonic behaviour. Addition of a poorer cosolvent, such as glycerol, to aqueous polysaccharide solutions induces flexible coil → swollen → collapsed conformational transitions as the solvent quality becomes progressively poorer. Using complementary simulations, theory, and experiments, we show that preferential solvation governs the conformational transitions, where the distribution of solvent molecules around the polysaccharide chain deviates significantly from that in the bulk solution. Contrary to expectations, initial chain swelling arises from preferential binding of glycerol at lower glycerol volume fraction, whereas preferential hydration leads to a more compact (collapsed) configuration at higher glycerol volume fraction. Chains appear to conserve their total water contact via such conformational reconfigurations, which map directly onto viscoelastic response; a phenomenon that may be greatly accentuated in polysaccharides. Results are explained from the perspective of Kirkwood-Buff solution theory and solvent entropic penalties, which extend beyond the Flory-type mean-field description. A tentatively unified behaviour can be observed across complex polysaccharides, including pectin, as well as other linear and branched polysaccharides such as agar, alginate, carboxymethylcellulose, and dextran, suggesting potential fundamental significance for biological and industrial aspects of glycoscience.

Keyword(s): Polymers, Soft Nano Particles and Proteins (1st) ; Soft Condensed Matter (2nd)

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Contributing Institute(s):

1. Technische Universität München (TUM)

Research Program(s):

1. GNeuS - Global Neutron Scientists (101034266) (101034266)

Experiment(s):

1. TOFTOF: Cold neutron time-of-flight spectrometer (NL2au)

Appears in the scientific report 2026

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Database coverage:
; BIOSIS Previews ; Biological Abstracts ; Clarivate Analytics Master Journal List ; Current Contents - Agriculture, Biology and Environmental Sciences ; Current Contents - Life Sciences ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF >= 10 ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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