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Control de las dimensiones y la quiralidad supramolecular de los autoensamblajes a través de la luz y los iones
Guofeng Liu1, Jianhui Sheng1, Wei Liang Teo1
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore.
Journal of the American Chemical Society
|November 8, 2018
Resumen
Los químicos y científicos de materiales ahora pueden controlar las dimensiones y la quiralidad del autoensamblaje molecular. Un conjugado de colesterol y azopiridina forma organogeles que se transforman de microbeltas a nanopartículas utilizando iones de luz y metal.
Área de la Ciencia:
- Química supramolecular
- Ciencias de los materiales
- Química orgánica
Sus antecedentes:
- El control de la quiralidad helicoidal y las dimensiones de los autoensamblajes moleculares es crucial para las propiedades de los materiales supramoleculares.
- Los métodos existentes se enfrentan a desafíos para lograr un control preciso.
Objetivo del estudio:
- Desarrollar un sistema para transiciones dimensionales fotocontrolables en autoensamblajes moleculares.
- Investigar el papel de la fotoisomerización E/Z y la coordinación del metal en el control del autoensamblaje.
- Para lograr una quiralidad helicoidal ajustable en estructuras autoensambladas.
Principales métodos:
- Síntesis de un conjugado de colesterol y azopiridina.
- Fabricación de organogeles.
- Control fotoquímico mediante la fotoisomerización E/Z de la unidad de azopiridina.
- Cambios estructurales mediados por iones metálicos.
- Caracterización mediante microscopía electrónica de barrido (SEM), microscopía de fuerza atómica (AFM), dicroísmo circular (CD) y cristalografía de rayos X.
Principales resultados:
- El conjugado colesterol-azopiridina se autoensambla en organogeles.
- Se observaron transiciones dimensionales fotocontrolables: microbeltas 2D a nanotubos 1D a nanopartículas 0D.
- La fotoisomerización E / Z de la fracción de azopiridina impulsa la transformación dimensional.
- Coordinación de iones metálicos inducida por la inversión de la helicidad en las estructuras autoensambladas.
Conclusiones:
- El diseño racional de los bloques de construcción permite un control preciso de las dimensiones y la quiralidad del autoensamblaje.
- El sistema desarrollado ofrece una plataforma para crear materiales supramoleculares avanzados.
- Las aplicaciones potenciales incluyen pantallas inteligentes, optoelectrónica y catálisis asimétrica.
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