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Cicloadición de azida alquina promovida por cepa para la funcionalización de dendrones y dendrímeros basados en poli

Cátia Ornelas¹, Johannes Broichhagen, Marcus Weck

¹Molecular Design Institute and Department of Chemistry, New York University, New York, New York 10003-6688, USA.

Journal of the American Chemical Society

|February 27, 2010

Resumen

Las reacciones catalizadas por el cobre dejan residuos de metales tóxicos en los dendrones funcionalizados. Un nuevo método de química de clic sin cobre (SPAAC) ofrece una forma limpia y eficiente de crear dendrones PEGilados para usos biológicos.

Área de la Ciencia:

Química de Polímeros La Química de Polímeros es la química de los polímeros.
Ciencia de los Biomateriales Ciencia de los Biomateriales.
Síntesis orgánica La síntesis orgánica.

Sus antecedentes:

La cicloadición de azido de alquino catalizado por cobre (CuAAC) es ampliamente utilizada para la funcionalización de polímeros.
CuAAC a menudo resulta en contaminación de metales, lo que limita las aplicaciones en biología.
Los dendrones basados en poli (amido) funcionalizados con cadenas de polietilenglicol (PEG) son valiosos para aplicaciones biomédicas.

Objetivo del estudio:

Desarrollar un método libre de metales para la PEGilación de dendrones y dendrímeros a base de poli (amido).
Para abordar el problema de la contaminación por cobre en la funcionalización de los dendronos.
Establecer la cicloadición de azido alquino promovida por cepa (SPAAC) como una técnica viable para la modificación de dendrímeros.

Principales métodos:

Variantes investigadas de CuAAC, incluidos aditivos y alambre de cobre, para reducir la contaminación.
Desarrolló e implementó una estrategia SPAAC libre de cobre para la PEGilación de dendros.
Caracterizó los dendrones PEGilados resultantes utilizando RMN (1H, 13C, HSQC, COSY), espectrometría de masas y análisis elemental.

Principales resultados:

Las estrategias CuAAC no lograron producir dendrones libres de cobre debido a la complicación del catalizador.
SPAAC logró con éxito la PEGilación cuantitativa de dendrones y dendrímeros basados en poli (amido).
El método SPAAC produjo productos libres de contaminación metálica bajo condiciones suaves.

Conclusiones:

SPAAC es un método altamente efectivo y libre de metales para la funcionalización de dendrímeros y dendronas.
Este enfoque supera las limitaciones de CuAAC con respecto a la contaminación por metales.
SPAAC ofrece una herramienta prometedora para la creación de biomateriales avanzados para diversas aplicaciones.

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