Inactivation of Ice Nucleating Activity of Silver Iodide by Antifreeze Proteins and Synthetic Polymers

Antifreeze proteins (AFPs) and poly­(vinyl alcohol) (PVA) are known as anti-ice nucleating agents (anti-INAs), which inhibit ice nucleation initiated by ice nucleating agents (INAs). Although the effectiveness of anti-INAs depends on the type of INA, most previous studies on anti-INAs used only a few types of biological INAs as targets to inactivate. In this study, the effects of fish AFPs (AFP I and AFP III) and PVA on the ice nucleating activity of silver iodide (AgI) were measured by using emulsified solutions. Results showed that AgI was inactivated not only by AFPs and PVA but also by two other polymers previously not considered as anti-INAs, namely, poly­(vinylpyrrolidone) and poly­(ethylene glycol). Even in the presence of AgI, a non-negligible fraction, typically more than 10%, of emulsified droplets of these anti-INA solutions at 1.0 mg mL^–1 was supercooled to about −37 °C, which corresponds to ice nucleation temperature measured in the absence of AgI

Direct Visualization of Spatiotemporal Structure of Self-Assembled Colloidal Particles in Electrohydrodynamic Flow of a Nematic Liquid Crystal

Characterization of spatiotemporal dynamics is of vital importance to soft matter systems far from equilibrium. Using a confocal laser scanning microscopy, we directly reveal three-dimensional motion of surface-modified particles in the electrohydrodynamic convection of a nematic liquid crystal. Particularly, visualizing a caterpillar-like motion of a self-assembled colloidal chain demonstrates the mechanism of the persistent transport enabled by the elastic, electric, and hydrodynamic contributions. We also precisely show how the particles’ trajectory is spatially modified by simply changing the surface boundary condition

Direct Visualization of Spatiotemporal Structure of Self-Assembled Colloidal Particles in Electrohydrodynamic Flow of a Nematic Liquid Crystal

Characterization of spatiotemporal dynamics is of vital importance to soft matter systems far from equilibrium. Using a confocal laser scanning microscopy, we directly reveal three-dimensional motion of surface-modified particles in the electrohydrodynamic convection of a nematic liquid crystal. Particularly, visualizing a caterpillar-like motion of a self-assembled colloidal chain demonstrates the mechanism of the persistent transport enabled by the elastic, electric, and hydrodynamic contributions. We also precisely show how the particles’ trajectory is spatially modified by simply changing the surface boundary condition