Analyzing the Ability to Sort DNA by Size using an Array of Viscous Obstacles and the Structure of a PhytoSpherix

Speaker: Matthew Vandesande

Affiliation: UOIT

Two research projects were conducted. The first project focused on examining the ability to sort DNA by
size through a square array of viscous obstacles and the second project examined the structure of a
PhytoSpherix particle.
Previous studies in the literature have shown that a DNA travelling through a system of hard posts
generates a length-dependent mobility. This provides a mechanism by which a microfluidic array can sort
DNA by length. However, it is unknown how this length-dependent behaviour changes if these systems
contain viscous inclusions rather than hard posts. A coarse-grained Langevin dynamic simulation approach
is utilized to examine the mobility of a polymer chain within a square lattice of viscous obstacles. These
simulations reveal that the dependence of the polymers mobility as a function of its length can be stronger
inside a system of viscous obstacles than in a system of hard posts. This implies that a square lattice of
viscous obstacles may be useful for sorting DNA by size.
PhytoSpherix are phytoglycogen-based nanoparticles that are found in sweet corn and thus are a
biodegradable, “green” nanotechnology. Further, being composed of polysaccharides, they are
biocompatible and show promise as a means of drug delivery. However, many questions remain
concerning the details of the structure of these particles. For example, different experimental techniques
yield different results for the size of the structure. In this project, we use simulations to produce coarse-
grained models of the particle structure. Langevin dynamic simulations of particle synthesis are performed.
The final structures are examined to determine the radial density of the structure and the number of water
molecules inside the particle. Simulations suggest that these structures resemble hairy colloids, with a
dense inner core and a sparse outer shell. Conversely, the dissolved water content is approximately
constant in the inner core but grows rapidly in the outer shell.