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Synthesis, Cellular Delivery and In vivo Application of Dendrimer-based pH Sensors
Published on: September 10, 2013
Respuesta al pH de los poli (óxido de etileno) de tipo dendrimero
Xiaoshuang Feng1, Daniel Taton, Redouane Borsali
1Laboratoire de Chimie des Polymères Organiques, Ecole Nationale Supérieure de Chimie et Physique de Bordeaux-Université Bordeaux-1-CNRS 16, Avenue Pey Berland, 33607 Pessac Cedex, France.
Journal of the American Chemical Society
|August 31, 2006
Resumen
Los investigadores crearon sistemas unimoleculares sensibles al pH utilizando un andamio de poli (óxido de etileno) parecido a un dendrimero con cadenas internas de ácido poli (ácido acrílico). Estas estructuras se contraen de manera reversible y se expanden con los cambios de pH, evitando la agregación a través de la complicación intramolecular.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- El óxido de polietileno (PEO) y el ácido poliacrílico (PAA) son conocidos por su agregación sensible al pH a través de interacciones no covalentes.
- El control de la arquitectura del polímero es clave para diseñar materiales sensibles y evitar la agregación macroscópica.
Objetivo del estudio:
- Para sintetizar sistemas unimoleculares con capacidad de respuesta al pH mediante el ensamblaje de PEO y PAA en una arquitectura específica de tipo dendrimero.
- Para explotar la complejidad intramolecular entre las unidades de PAA y PEO para cambios de tamaño reversibles inducidos por el pH.
- Para evitar la complejación intermolecular y la agregación macroscópica.
Principales métodos:
- Síntesis de un andamio PEO de quinta generación similar a un dendrimero utilizando polimerización de apertura de anillo aniónico (AROP) y un nuevo agente de ramificación AB(2) C.
- Funcionalización de los grupos vinílicos internos del andamio PEO en cadenas de ácido poliacrílico (PAA) a través de sitios de iniciación de la polimerización radical de transferencia atómica (ATRP).
- Caracterización de los PEOs similares a dendrímeros portadores de PAA resultantes utilizando dispersión dinámica de la luz (DLS) para evaluar las variaciones de tamaño dependientes del pH.
Principales resultados:
- Se ha sintetizado con éxito PEOs hidrófilos, similares a los dendrímeros, con 21 bloques internos de PAA unidos a las uniones.
- Se ha demostrado un comportamiento sensible al pH donde los sistemas unimoleculares se contraen y expanden de forma reversible en el agua.
- Se confirmó que la arquitectura específica previene la complicación intermolecular, favoreciendo las interacciones intramoleculares.
Conclusiones:
- La arquitectura PEO diseñada en forma de dendrimero controla efectivamente el autoensamblaje de las cadenas PEO y PAA.
- Estos sistemas unimoleculares exhiben un comportamiento sintonizable, reversible y sensible al pH debido a la complicación intramolecular PAA-EO.
- Este enfoque ofrece una estrategia novedosa para la creación de materiales poliméricos sensibles avanzados.
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