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Moldeo con disolvente de morfologías orgánicas hechas de polímeros quirales supramoleculares
Luka Đorđević1, Tomas Marangoni1, Tanja Miletić1
1†Department of Chemical and Pharmaceutical Sciences, INSTM UdR Trieste, University of Trieste, Piazzale Europa 1, 34127 Trieste, Italy.
Journal of the American Chemical Society
|May 21, 2015
Resumen
Los investigadores exploraron cómo las moléculas BINOL y OPE conjugadas con uracilo se autoensamblan en diversas nanoestructuras. Las propiedades del disolvente dictan la morfología, con estructuras helicoidales que exhiben una quiralidad única a nivel microscópico.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
- Química orgánica es la química orgánica.
Sus antecedentes:
- El autoensamblaje y la autoorganización son procesos fundamentales en la creación de arquitecturas moleculares complejas.
- El reconocimiento quiral y la formación de nanoestructuras quirales son cruciales para materiales avanzados y aplicaciones biológicas.
Objetivo del estudio:
- Para investigar el comportamiento de autoensamblaje de los cromóforos de enantiopuro (R) - o (S) -1,1'-binaftil-2,2'-diol (BINOL) y oligo(p-fenilenoetileno) (OPE) conjugados con uracilo.
- Comprender cómo las propiedades de los disolventes influyen en la formación y morfología de las nanoestructuras orgánicas.
Principales métodos:
- Las técnicas espectroscópicas incluyen UV-vis, dicroísmo circular (CD), fluorescencia y resonancia magnética nuclear (RMN).
- Diseminación de rayos X de ángulo pequeño (SAXS) para el análisis estructural.
- Métodos de microscopía como la microscopía de electrones de transmisión (TEM) y la microscopía de fuerza atómica (AFM).
- Simulaciones de modelado molecular.
Principales resultados:
- El reconocimiento del triple enlace H entre las unidades BINOL y OPE impulsa el autoensamblaje.
- Formación de varias nanoestructuras (esféricas, en forma de varilla, fibrosas, helicoidales) dependientes de la solvofobia al disolvente.
- Las nanoestructuras helicoidales fueron las únicas que exhibieron quiralidad microscópica.
- SAXS y el modelado revelaron superestructuras helicoidales compuestas de cintas de doble cable dimérico superenrolladas.
Conclusiones:
- La interacción del enlace H, la presión de vapor del disolvente y las interacciones solvófobas / solvófilas gobiernan la formación de nanoestructuras.
- La quiralidad se expresa a nivel microscópico en superestructuras helicoidales específicas.
- Este estudio proporciona información sobre el diseño y el control de ensamblajes supramoleculares quirales.
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