Phytoglycogen: soft nanoparticles with tunable properties
John R. Dutcher, Department of Physics, University of Guelph
I will introduce you to a unique material, phytoglycogen (PG), that is produced as compact nanoparticles in the kernels of sweet corn. Chemically, PG is very simple, consisting only of glucose. However, the physical arrangement of the large number of glucose units in a tree-like or dendritic architecture produces a range of interesting and useful physical properties: it is soft, porous, hydrated and hairy. We have used PG to probe fundamental issues in soft matter physics such as the soft colloidal glass transition and the structuring of nanoconfined water within the particles. Their physical properties combined with their non-toxicity and digestibility also make them ideal for use in applications involving the human body such as personal care, nutrition and biomedicine. I will describe our investigations of the physical properties of PG nanoparticles through a broad range of experiments and computer simulations. In addition, I will discuss how the properties of PG can be tuned through simple modifications: controlled digestion and covalent attachment of chemical groups that can impart different functionalities such as charge and hydrophobicity. These simple modifications have produced significant and sometimes dramatic changes to the physical properties of the particles, opening up new applications of this sustainable nanotechnology. This talk is intended for physics and chemistry senior undergraduate students.
