초록 |
The cholesteric liquid crystal (CLC) droplets were prepared with MLC-2132 (Merck) doped with (S)-4-cyano-4´-(2-methylbutyl)biphenyl (CB15) (Synthon) by a microfluidic method. The droplets were prepared with aqueous solutions of poly-vinyl alcohol (PVA) and sodium dodecylsulfate (SDS) in continuous phase, which cause parallel and perpendicular anchorings of LC in the droplet, respectively. The helical structure was strongly dependent on the used surfactant. The CLC droplets with parallel and perpendicular anchorings had concentric rings with their centers at the center and off the center of the droplet, respectively. These two helical structures were reversibly changed each other by exposing the LC droplet (prepared in one surfactant) in the other surfactant solution. This structural change was applied to the biosensor by employing the pH-responsive polyelectrolyte on the surface with a block copolymer consisting of liquid crystal and polyelectrolyte blocks as a surfactant. |