1 research outputs found
Structure and Hydration of Highly-Branched, Monodisperse Phytoglycogen Nanoparticles
Phytoglycogen
is a naturally occurring polysaccharide nanoparticle
made up of extensively branched glucose monomers. It has a number
of unusual and advantageous properties, such as high water retention,
low viscosity, and high stability in water, which make this biomaterial
a promising candidate for a wide variety of applications. In this
study, we have characterized the structure and hydration of aqueous
dispersions of phytoglycogen nanoparticles using neutron scattering.
Small angle neutron scattering results suggest that the phytoglycogen
nanoparticles behave similar to hard sphere colloids and are hydrated
by a large number of water molecules (each nanoparticle contains between
250% and 285% of its mass in water). This suggests that phytoglycogen
is an ideal sample in which to study the dynamics of hydration water.
To this end, we used quasielastic neutron scattering (QENS) to provide
an independent and consistent measure of the hydration number, and
to estimate the retardation factor (or degree of water slow-down)
for hydration water translational motions. These data demonstrate
a length-scale dependence in the measured retardation factors that
clarifies the origin of discrepancies between retardation factor values
reported for hydration water using different experimental techniques.
The present approach can be generalized to other systems containing
nanoconfined water