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Updated: Jun 4, 2026
10:35
Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Light and Dark Cycles Control the Structural Evolution of Photoresponsive Supramolecular Systems
Alejandro Méndez-Ardoy1,2, Nicolas Cissé3, Adrian Sanchez-Fernandez4
1Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Sevilla, Spain.
Angewandte Chemie (International Ed. in English)
|June 3, 2026
Summary
Alternating light and dark periods promote the formation of stable supramolecular structures from photoswitchable peptides, unlike continuous light. This highlights the crucial role of rest in self-assembly pathway selection for molecular systems.
Area of Science:
- Supramolecular Chemistry
- Photochemistry
- Materials Science
Background:
- Living systems utilize cyclic light and dark periods for adaptation and organization.
- While light-driven supramolecular assembly is known, structural adaptation to alternating light/dark cycles in synthetic systems is understudied.
Purpose of the Study:
- To investigate how oscillating light energy supply influences the structural selection of self-assembling photoswitchable peptides.
- To compare the effects of alternating light/dark input versus continuous illumination on supramolecular architecture formation.
Main Methods:
- Utilized photoswitchable peptides capable of self-assembly.
- Applied oscillating light/dark cycles and continuous illumination as stimuli.
- Characterized the resulting supramolecular structures.
Main Results:
- Polymorphic self-assembled structures were transiently formed and sustained only under light irradiation.
- Alternating light and darkness periods favored the formation of a thermodynamically more stable supramolecular architecture.
- Continuous illumination did not yield the same stable structures.
Conclusions:
- Oscillating light energy supply can facilitate structural selection in self-assembling photoswitchable peptides.
- Rest periods (darkness) play a critical role in selecting thermodynamically stable supramolecular architectures.
- Findings offer insights into designing self-organized supramolecular photosystems with controlled structural outcomes.
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