Europhys. Lett.
Volume 65, Number 1, January 2004
Page(s) 41 - 47
Section Condensed matter: structure, mechanical and thermal properties
Published online 01 December 2003
Europhys. Lett., 65 (1) , pp. 41-47 (2004)
DOI: 10.1209/epl/i2003-10052-0

Comparative study of trehalose, sucrose and maltose in water solutions by molecular modelling

P. Bordat, A. Lerbret, J.-P. Demaret, F. Affouard and M. Descamps

Laboratoire de Dynamique et Structure des Matériaux Moléculaires UMR 8024, Université Lille I - 59655 Villeneuve d'Ascq cedex, France

(Received 4 September 2003; accepted 28 October 2003)

A systematic study of three well-known bioprotectant sugars -trehalose, sucrose and maltose- in water solutions has been performed at different concentrations and temperatures using molecular-dynamics simulations. A variety of relevant probes such as the size of hydrogen-bonded water clusters, the orientational order parameter q, the Voronoi volume and the dynamical structure factor have been determined to describe the effect of the three disaccharides on water quantitatively. This investigation points out different structural and dynamical behaviours for which a threshold concentration $\phi_{A}$ and a crossover temperature TA emerge. A "destructuring" effect on the water network and a slowing-down of its dynamics are highlighted. These results suggest narrow links between the different scenarios tentatively explaining bioprotection.

61.20.Ja - Computer simulation of liquid structure.
64.60.Ht - Dynamic critical phenomena.
64.70.Pf - Glass transitions.

© EDP Sciences 2004