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Abstract The vast majority of nanomaterials studied in light of their ability to transmit chirality to or amplify their chirality in a surrounding medium, constitute an achiral core with chirality solely installed at the surface by conjugation or encapsulation with optically active ligands. Here we present the inverse approach focusing on surface‐modified cellulose nanocrystals (CNCs) with core chirality at both the molecular and the morphological level to quantify transmission and amplification of core chirality through space using a host nematic liquid crystal (N‐LC) as reporter. We find that CNCs functionalized at the surface with achiral molecules, structurally related to the N‐LC, exhibit better N‐LC solubility, thereby serving as highly efficient chiral inducers. Moreover, functionalization with chiral molecules only marginally enhances the efficacy of helical distortion in the host N‐LC matrix, indicating the high propensity of CNCs to transfer chirality from an inherently chiral core.
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The significance of nanoparticle shape in chirality transfer to a surrounding nematic liquid crystal reporter medium
Defined based on geometric concepts, the origin of biological homochirality including the single handedness of key building blocks, D-sugars and L-amino acids, is still heavily debated in many ongoing research endeavors. Origin aside, transmission and amplification of chirality across length scales are likely essential for the predominance of one handedness over the other in chiral systems and are attracting an unabated interest not only in biology but also in material science. To offer a measure for chirality and through-space chirality transfer, we here provide a report on recent progress toward the development of a suitable approach for an a priori prediction of chirality “strength” and efficacy of chirality transfer from a chiral solute to an achiral nematic solvent. We achieve this by combining an independently calculated, suitable pseudoscalar chirality indicator for the solute with another, independently calculated scalar solute–solvent shape compatibility factor. In our ongoing pursuit to put this approach to the test, we are advancing and refining a versatile experimental platform based on achiral gold nanoparticle cores varying in size, shape, and aspect ratio capped with monolayers of chiral molecules or on intrinsically chiral cellulose nanocrystals that serve as chiral solutes in an achiral nematic liquid crystal phase acting as a reporter medium. The pitch of the ensuing induced chiral nematic liquid crystal phase ultimately serves as a reporter medium that allows us to experimentally quantify and compare chirality and efficacy of chirality transfer.
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- Award ID(s):
- 1904091
- PAR ID:
- 10379167
- Date Published:
- Journal Name:
- Materials Advances
- Volume:
- 3
- Issue:
- 8
- ISSN:
- 2633-5409
- Page Range / eLocation ID:
- 3346 to 3354
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d2ma00093h
