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Conjugación macromolecular (ultra) rápida sin catalizador en el medio acuoso a temperatura ambiente
Mathias Glassner1, Guillaume Delaittre, Michael Kaupp
1Preparative Macromolecular Chemistry, Institut für Technische Chemie und Polymerchemie and Centre for Functional Nanostructures, Karlsruhe Institute of Technology, Engesserstrasse 18, 76128 Karlsruhe, Germany.
Journal of the American Chemical Society
|April 18, 2012
Resumen
Los polímeros solubles en agua reaccionan de manera eficiente en el agua utilizando las cicloadiciones hetero-Diels-Alder (HDA). Este método libre de catalizadores permite la conjugación rápida de macromoléculas a temperatura ambiente, simplificando la síntesis de polímeros.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Síntesis orgánica La síntesis orgánica.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- La polimerización en vivo/controlada mediada por RAFT permite la síntesis de macromoléculas hechas a medida.
- Las reacciones Hetero-Diels-Alder (HDA) son conocidas por su eficiente conjugación en disolventes orgánicos.
- Las reacciones anteriores de HDA a menudo requerían catalizadores y temperaturas elevadas, lo que limita su aplicación en medios acuosos.
Objetivo del estudio:
- Para demostrar conjugaciones HDA libres de aditivos y catalizadores de macromoléculas hidrosolubles en agua.
- Para investigar la eficiencia y la cinética de las reacciones HDA en un ambiente acuoso.
- Mostrar la utilidad del glicopolímero polimerizado RAFT para aplicaciones de bioconjugación.
Principales métodos:
- Síntesis de un glicopolímero soluble en agua a través de la polimerización RAFT.
- Conjugación de un glicopolímero con polietilenglicol funcionalizado por dieno (PEG) en agua.
- Utilizando la química de la cicloadición hetero-Diels-Alder (HDA).
- Caracterización mediante el uso de ESI-MS, UV/vis, RMN y SEC.
Principales resultados:
- La conversión cuantitativa en conjugaciones HDA se logró en cuestión de minutos cuando se involucraron fracciones de ciclopentadienilo.
- Las cicloadiciones HDA libres de aditivos procedieron eficientemente en el agua en unas pocas horas a temperatura ambiente.
- La conjugación exitosa fue confirmada por el análisis ESI-MS, UV/vis, RMN y SEC.
Conclusiones:
- Las macromoléculas solubles en agua se pueden conjugar de manera eficiente en el agua utilizando reacciones HDA libres de catalizadores.
- Este método ofrece un enfoque simplificado y respetuoso con el medio ambiente para la modificación de polímeros y la bioconjugación.
- La metodología desarrollada amplía el alcance de las reacciones HDA para aplicaciones acuosas.
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