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Los portadores de autoensamblaje dinámico permiten la guía de partículas diamagnéticas por imanes débiles
Olga Chovnik1, Renata Balgley, Joel R Goldman
1Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
Journal of the American Chemical Society
|November 28, 2012
Resumen
Los investigadores guiaron de forma remota las partículas diamagnéticas utilizando nanopartículas superparamagnéticas con conmutación de luz. Estas nanopartículas se unen de manera reversible a las partículas diamagnéticas, lo que permite una entrega y liberación dirigidas con luz y calor.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- El magnetismo es el magnetismo.
Sus antecedentes:
- Los materiales diamagnéticos son típicamente rechazados por los campos magnéticos.
- La manipulación remota de micro / nanopartículas es crucial para la entrega y el ensamblaje específicos.
- El control de las interacciones de partículas a nanoescala requiere materiales sensibles avanzados.
Objetivo del estudio:
- Desarrollar un método para la manipulación remota de partículas diamagnéticas.
- Para utilizar nanopartículas de respuesta dual para el ensamblaje y desmontaje controlado de partículas.
- Para demostrar la entrega dirigida y la liberación de partículas diamagnéticas utilizando la luz y los campos magnéticos.
Principales métodos:
- Síntesis de nanopartículas de respuesta dual con propiedades de conmutación de luz y superparamagnéticas.
- Demostración de la adsorción reversible de nanopartículas en superficies de partículas diamagnéticas activadas por la luz UV.
- Utilizando la luz térmica o ambiental para la desorción de nanopartículas.
- Inducir interacciones atractivas a través del autoensamblaje dinámico de las películas de nanopartículas.
- Guía magnética y entrega remota de partículas diamagnéticas funcionalizadas.
Principales resultados:
- Se logró con éxito la manipulación remota de partículas diamagnéticas utilizando imanes externos.
- Se ha demostrado la adsorción/desorción de nanopartículas reversibles mediante UV y luz visible, respectivamente.
- Se demostró la reversibilidad térmica y de la luz ambiente para el desmontaje de la capa de nanopartículas.
- Las cantidades catalíticas de nanopartículas de respuesta dual fueron suficientes para la guía de partículas.
- Se logró la entrega dirigida y la liberación controlada de partículas diamagnéticas.
Conclusiones:
- Las nanopartículas de doble respuesta permiten una efectiva manipulación magnética remota de las partículas diamagnéticas.
- El montaje/desmontaje reversible activado por luz ofrece un control preciso sobre las interacciones y el posicionamiento de las partículas.
- Esta técnica proporciona una plataforma novedosa para aplicaciones de entrega dirigida y liberación controlada en varios campos.
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