Dynamic helical structures: Detection and amplification of chirality

A unique feature of dynamic helical, chromophoric macromolecules that enables the detection of a small imbalance in chiral guest molecules through a noncovalent bonding interaction with high cooperativity is described. In sharp contrast to host-guest and supramolecular systems based on small synthetic receptor molecules, the chiral information of nonracemic guest molecules transfers with a significant amplification in a helical polymer as an excess of a single-handed helix, resulting in a highly efficient chirality-sensing system. Helical aggregates with controlled helicity based on small molecules and their chiral amplification and use in chirality sensing are also briefly described in this review.