Migration Behavior of Bio-materials in Ice Grain Boundary Channels

Abstract

In this chapter, the migration behavior of bio-materials in ice grain boundaries is explored to demonstrate the applicability of the concept proposed in Chap. 2 to bio-separation. Yeast cells and T4 GT7 giant DNA samples were employed. The size-tunability of the ice grain boundary channel (Inagawa et al. in Sci Rep 5:17308 [1], Inagawa et al. in Talanta 183:345–351 [2]) allows the migration control of yeast cells. On the other hand, for DNA, the difference in the migration behavior of the random-coil and globule states was investigated. This difference in state affects the contour flexibility of the DNA, resulting in different threshold temperatures at which the DNA molecules begin to migrate. Ice grain boundary electrophoresis was also applied to the detection of the chemical interactions between the biomolecules and ice crystals. AFPs were anchored on 1 μm PS particles, and their migration behavior in the grooves on the surface ice was studied. The threshold temperature at which the particles begin to migrate is an effective criterion for the evaluation of the chemical interactions between the particles and ice walls. The threshold temperature was lowered by 2.5 °C when the AFPs were bound onto the particles, indicating the presence of interactions between the bound AFPs and the ice wall. Because the AFPs studied in this work exhibit selectivity towards the prism plane of the ice crystal, it is critical that the prism plane of the ice crystal should be in contact with the FCS in the surface grooves.