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A Micropatterning Assay for Measuring Cell Chirality
Published on: March 11, 2022
Steering organizational and conformational surface chirality by controlling molecular chemical functionality.
Christian Bombis1, Sigrid Weigelt, Martin M Knudsen
1Interdisciplinary Nanoscience Center (iNANO) and Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
ACS Nano
|December 17, 2009
Summary
This study explores molecular chirality in organic molecules adsorbed on surfaces. Researchers found that controlling molecular structure can dictate surface assembly chirality, enabling design of chiral or achiral surface structures.
Area of Science:
- Surface science
- Supramolecular chemistry
- Chirality studies
Background:
- Molecular chirality on surfaces is well-studied, but effects from conformational degrees of freedom are less explored.
- Adsorption of achiral molecules can induce chirality due to reduced symmetry and surface confinement.
Purpose of the Study:
- Investigate self-assembled structures of linear organic molecules (oligo-phenylene-ethynylenes) on Au(111).
- Analyze conformational chirality, point chirality, and organizational chirality in adsorbed molecules.
- Demonstrate control over molecular chirality through terminal group functionalization.
Main Methods:
- Scanning tunneling microscopy (STM) under ultrahigh vacuum conditions.
- Systematic investigation of eleven observed adsorption structures.
- Analysis of molecular conformations and assembly patterns.
Main Results:
- Achiral oligo(phenylene-ethynylenes) exhibit conformational chirality, forming chiral enantiomers or achiral meso forms upon adsorption.
- Identified correlations between conformational, point, and organizational chirality.
- Demonstrated control over organizational chirality (chiral vs. mirror-symmetric tiling) and conformational chirality (chiral vs. achiral conformers) via terminal group functionalization.
Conclusions:
- Terminal group functionalization is a key strategy to control chirality in molecular self-assembly on surfaces.
- It is possible to design surface assemblies with specific chiral properties, including pronounced organizational chirality or mirror-symmetric patterns.
- Conformational chirality can be selectively controlled, favoring either chiral or achiral surface conformers.
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