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Chiral shape fluctuations and the origin of chirality in cholesteric phases of DNA origamis.

ABSTRACT: Lyotropic cholesteric liquid crystal phases are ubiquitously observed in biological and synthetic polymer solutions, characterized by a complex interplay between thermal fluctuations and entropic and enthalpic forces. The elucidation of the link between microscopic features and macroscopic chiral structure, and of the relative roles of these competing contributions on phase organization, remains a topical issue. Here, we provide theoretical evidence of a previously unidentified mechanism of chirality amplification in lyotropic liquid crystals, whereby phase chirality is governed by fluctuation-stabilized helical deformations in the conformations of their constituent molecules. Our results compare favorably to recent experimental studies of DNA origami assemblies and demonstrate the influence of intramolecular mechanics on chiral supramolecular order, with potential implications for a broad class of experimentally relevant colloidal systems.

SUBMITTER: Tortora MMC

PROVIDER: S-EPMC7399560 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Chiral shape fluctuations and the origin of chirality in cholesteric phases of DNA origamis.

Tortora Maxime M C MMC Mishra Garima G Prešern Domen D Doye Jonathan P K JPK

Science advances 20200729 31

Lyotropic cholesteric liquid crystal phases are ubiquitously observed in biological and synthetic polymer solutions, characterized by a complex interplay between thermal fluctuations and entropic and enthalpic forces. The elucidation of the link between microscopic features and macroscopic chiral structure, and of the relative roles of these competing contributions on phase organization, remains a topical issue. Here, we provide theoretical evidence of a previously unidentified mechanism of chir ...[more]

PMID: 32789165

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