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Los túbulos pulsantes de los macrociclos no covalentes
Zhegang Huang1, Seong-Kyun Kang, Motonori Banno
1Department of Chemistry, Seoul National University, Seoul 151-747, Korea.
Science (New York, N.Y.)
|September 22, 2012
Resumen
Los investigadores desarrollaron nanotúbulos supramoleculares dinámicos que se contraen y expanden, cambiando su quiralidad helicoidal. Estas estructuras autoensambladas pueden encapsular huéspedes hidrofóbicos como el carbono-60 (C60) y responder a desencadenantes externos.
Área de la Ciencia:
- Se trata de una química supramolecular.
- Ciencia de los materiales ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Lograr una respuesta dinámica en ensamblajes tubulares sintéticos a escala nanométrica es un desafío.
- Las estructuras de nanotúbulos existentes a menudo carecen de capacidad de respuesta a estímulos externos.
Objetivo del estudio:
- Diseñar y sintetizar nanotúbulos supramoleculares con movimiento dinámico y reversible.
- Para investigar el mecanismo de la contracción-expansión y la inversión quiral.
- Para explorar la encapsulación de huéspedes hidrofóbicos dentro de estos túbulos dinámicos.
Principales métodos:
- Autoensamblaje de anfífilos aromáticos de forma doblada en solución acuosa.
- Formación de macrociclos hexaméricos y su posterior apilamiento unidimensional en túbulos quirales.
- Utilizando disparadores externos para inducir el deslizamiento reversible de los segmentos aromáticos.
- Encapsulación de huéspedes hidrofóbicos, específicamente el carbono-60 (C60).
Principales resultados:
- Se sintetizaron con éxito nanotúbulos supramoleculares que exhiben movimiento de contracción-expansión reversible.
- El movimiento dinámico fue acompañado por una inversión reversible de la quiralidad helicoidal.
- Los nanotúbulos demostraron la capacidad de encapsular huéspedes hidrofóbicos como el C60 dentro de su interior aromático.
- Se utilizaron disparadores térmicos para regular las interacciones huésped-huésped a través de la pulsación de nanotúbulos.
Conclusiones:
- Las anfifilas aromáticas de forma curvada pueden autoensamblarse en nanotúbulos quirales dinámicos con propiedades sensibles.
- El movimiento pulsante observado y la inversión quiral ofrecen un nuevo mecanismo para estructuras dinámicas a nanoescala.
- Estos nanotúbulos funcionales muestran potencial para la encapsulación controlada y la modulación de la interacción de las moléculas hidrofóbicas.
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