Chirality Differentiation by Diffusion in Chiral Nematic Liquid Crystals

Abstract

The chirality (handedness) of molecules is important in physics, chemistry, and especially biology, where enantiomers can have drastically different effects on a living system. Chiral rodlike molecules can self-assemble into a liquid-crystalline helical structure with orientational order. The authors show that such a structure differentiates chiral guest molecules diffusing through it: Guests of the same handedness traverse the host more rapidly than those of opposite orientation. This could be used to separate enantiomers, yielding pure pharmaceuticals, for example.