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Microgeles híbridos fotorresponsivos en el rango espectral del infrarrojo cercano
Ivan Gorelikov1, Lora M Field, Eugenia Kumacheva
1Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M6S 3H6, Canada.
Journal of the American Chemical Society
|December 9, 2004
Resumen
Desarrollamos un nuevo material compuesto utilizando microgeles de polímero y nanorodos de oro. Este material responde a la luz, permitiendo la liberación controlada de fármacos y proteínas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
Sus antecedentes:
- El desarrollo de materiales inteligentes para la administración de sustancias controladas es crucial.
- Los efectos fototérmicos ofrecen un disparador no invasivo para la respuesta del material.
- Los nanorodos de oro exhiben propiedades ópticas sintonizables para la absorción del infrarrojo cercano.
Objetivo del estudio:
- Para crear un material compuesto fototérmicamente sensible.
- Para funcionalizar microgeles de polímero con nanorods de oro para la activación desencadenada por luz.
- Investigar el potencial de este compuesto para la administración de fármacos y proteínas.
Principales métodos:
- La síntesis de nanorodos de oro con relaciones de aspecto específicas para la absorción del infrarrojo cercano.
- Incorporación de nanorodos de oro en microgeles poli (N-isopropilacrilamida-ácido acrílico) sensibles a la temperatura.
- Irradiando los microgeles híbridos con un láser de 810 nm para inducir efectos fototérmicos.
Principales resultados:
- Los nanorodos de oro fueron sintetizados con éxito con una fuerte absorción en la "ventana de agua" del infrarrojo cercano.
- Las partículas de microgel híbrido dopadas con nanorods de oro exhibieron una transición de fase de deswelling significativa después de la irradiación láser.
- El material demostró deswelling controlado, lo que indica el potencial para la liberación de la carga útil.
Conclusiones:
- Se ha desarrollado con éxito un nuevo material compuesto fototérmicamente sensible basado en microgeles de polímero y nanorodos de oro.
- El comportamiento de deswelling inducido por la luz del material se atribuye al efecto fototérmico de los nanorodos de oro.
- Este material compuesto se muestra prometedor para aplicaciones en medicamentos dirigidos y sistemas de administración de moléculas pequeñas.
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