STRUCTURAL AND DYNAMICAL STUDY OF CONFINED SUGAR
SOLUTIONS
Even though the active role of sugar molecules is well known
as stabilizer agent for cell membranes upon dehydration, the responsible
process is still unidentified. Nevertheless, the great affinity existing
between sugar and water molecules -- evidenced by the important number of
hydrogen bondings between these two species -- seems to be the main agent at
the origin of this exceptional property. An experimental study of sugar and
water molecules should allow to determine accurately the interactions causing
this remarkable resistance.
In this work, we focused on solutions of mono- and
disaccharides (glucose, fructose and trehalose). The quasi-elastic neutron
scattering is an appropriate tool to probe, at the picosecond timescale, the
dynamics of water and sugar in solution and under confinement in porous
materials presenting a scale mimicking the living world. Two matrices have been
chosen : silica gel and mesoporous silica spheres presenting pores of 18 and 3
nm respectively. Both have been characterized with a large set of experiments
(SANS, SEM, TEM, Raman Spectroscopy, BET, XRD). The effect of the confinement
on the dynamics and solid-liquid transitions have been explored, thus an
in-situ dehydration study monitored by small-angle neutron scattering allowed
us to better understand the bioprotective effect of theses sugars.
KEYWORDS : Sugars, mono- and disaccharides, aqueous
solution, synthesis, silica, gel, mesoporous spheres, MCM-41, confinement,
molecular dynamics, phase transition, QENS, SANS.
DISCIPLINE : Physique, mention Physique et Physico-chimie
de la matière et des matériaux
LABORATOIRE : Centre de Recherche sur la Matière
Divisée
1b, Rue de la Férollerie 45071 Orléans Cedex 2
France
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