Cargando…

Flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids

Liquid crystalline droplets, also known as tactoids, forming by nucleation and growth within the phase diagram region where isotropic and nematic phases coexist, challenge our understanding of liquid crystals under confinement due to anisotropic surface boundaries at vanishingly small interfacial te...

Descripción completa

Detalles Bibliográficos
Autores principales: Almohammadi, Hamed, Bagnani, Massimo, Mezzenga, Raffaele
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7591495/
https://www.ncbi.nlm.nih.gov/pubmed/33110064
http://dx.doi.org/10.1038/s41467-020-19213-x
_version_ 1783601006620180480
author Almohammadi, Hamed
Bagnani, Massimo
Mezzenga, Raffaele
author_facet Almohammadi, Hamed
Bagnani, Massimo
Mezzenga, Raffaele
author_sort Almohammadi, Hamed
collection PubMed
description Liquid crystalline droplets, also known as tactoids, forming by nucleation and growth within the phase diagram region where isotropic and nematic phases coexist, challenge our understanding of liquid crystals under confinement due to anisotropic surface boundaries at vanishingly small interfacial tension, resulting in complex, non-spherical shapes. Little is known about their dynamical properties, since they are mostly studied under quiescent, quasi-equilibrium conditions. Here we show that different classes of amyloid based nematic and cholesteric tactoids undergo order–order transitions by flow-induced deformations of their shape. Tactoids align under extensional flow, undergoing extreme deformation into highly elongated prolate shapes, with the cholesteric pitch decreasing as an inverse power-law of the tactoids aspect ratio. Free energy functional theory and experimental measurements are combined to rationalize the critical elongation above which the director-field configuration of tactoids transforms from bipolar and uniaxial cholesteric to homogenous and to debate on the thermodynamic nature of these transitions.
format Online
Article
Text
id pubmed-7591495
institution National Center for Biotechnology Information
language English
publishDate 2020
publisher Nature Publishing Group UK
record_format MEDLINE/PubMed
spelling pubmed-75914952020-11-10 Flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids Almohammadi, Hamed Bagnani, Massimo Mezzenga, Raffaele Nat Commun Article Liquid crystalline droplets, also known as tactoids, forming by nucleation and growth within the phase diagram region where isotropic and nematic phases coexist, challenge our understanding of liquid crystals under confinement due to anisotropic surface boundaries at vanishingly small interfacial tension, resulting in complex, non-spherical shapes. Little is known about their dynamical properties, since they are mostly studied under quiescent, quasi-equilibrium conditions. Here we show that different classes of amyloid based nematic and cholesteric tactoids undergo order–order transitions by flow-induced deformations of their shape. Tactoids align under extensional flow, undergoing extreme deformation into highly elongated prolate shapes, with the cholesteric pitch decreasing as an inverse power-law of the tactoids aspect ratio. Free energy functional theory and experimental measurements are combined to rationalize the critical elongation above which the director-field configuration of tactoids transforms from bipolar and uniaxial cholesteric to homogenous and to debate on the thermodynamic nature of these transitions. Nature Publishing Group UK 2020-10-27 /pmc/articles/PMC7591495/ /pubmed/33110064 http://dx.doi.org/10.1038/s41467-020-19213-x Text en © The Author(s) 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
spellingShingle Article
Almohammadi, Hamed
Bagnani, Massimo
Mezzenga, Raffaele
Flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids
title Flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids
title_full Flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids
title_fullStr Flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids
title_full_unstemmed Flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids
title_short Flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids
title_sort flow-induced order–order transitions in amyloid fibril liquid crystalline tactoids
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7591495/
https://www.ncbi.nlm.nih.gov/pubmed/33110064
http://dx.doi.org/10.1038/s41467-020-19213-x
work_keys_str_mv AT almohammadihamed flowinducedorderordertransitionsinamyloidfibrilliquidcrystallinetactoids
AT bagnanimassimo flowinducedorderordertransitionsinamyloidfibrilliquidcrystallinetactoids
AT mezzengaraffaele flowinducedorderordertransitionsinamyloidfibrilliquidcrystallinetactoids