title: Structure and Hydration of Highly-Branched, Monodisperse Phytoglycogen Nanoparticles.
abstract: 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.
authors: Joint Institute for Neutron Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.|Department of Physics, University of Tennessee , Knoxville, Tennessee 37996, United States.|Biology and Soft Matter Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
authors: Jonathan D
authors: JD
authors: Nickels
authors: Department of Physics, University of Guelph , Guelph, Ontario N1G 2W1, Canada.
authors: John
authors: J
authors: Atkinson
authors: Department of Physics, University of Guelph , Guelph, Ontario N1G 2W1, Canada.
authors: Erzsebet
authors: E
authors: Papp-Szabo
authors: Biology and Soft Matter Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
authors: Christopher
authors: C
authors: Stanley
authors: Chemical and Engineering Materials Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
authors: Souleymane O
authors: SO
authors: Diallo
authors: Department of Physics, University of Guelph , Guelph, Ontario N1G 2W1, Canada.
authors: Stefania
authors: S
authors: Perticaroli
authors: Department of Physics, University of Guelph , Guelph, Ontario N1G 2W1, Canada.
authors: Benjamin
authors: B
authors: Baylis
authors: Department of Physics, University of Guelph , Guelph, Ontario N1G 2W1, Canada.
authors: Perry
authors: P
authors: Mahon
authors: Quantum Condensed Matter Division, Oak Ridge National Laboratory , P.O. Box 2008, Oak Ridge, Tennessee 37831, United States.
authors: Georg
authors: G
authors: Ehlers
authors: Joint Institute for Neutron Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.|Department of Physics, University of Tennessee , Knoxville, Tennessee 37996, United States.|Biology and Soft Matter Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
authors: John
authors: J
authors: Katsaras
authors: Department of Physics, University of Guelph , Guelph, Ontario N1G 2W1, Canada.
authors: John R
authors: JR
authors: Dutcher
mesh_terms: D003102:Colloids / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D006003:Glycogen / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D053758:Nanoparticles / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D003102:Colloids; D006003:Glycogen; D005947:Glucose