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Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
Los anfífilos basados en poli (choloil) como agentes formadores de poros: monómeros transportadores activos por
Wen-Hua Chen1, Xue-Bin Shao, Steven L Regen
1Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
Journal of the American Chemical Society
|September 8, 2005
Resumen
Los investigadores diseñaron nuevos anfífilos formadores de poros. Algunos forman poros como moléculas individuales, mientras que otros forman poros basados en dímeros en bicapas lipídicas, ofreciendo propiedades supramoleculares controlables.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Química biofísica y bioquímica.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los anfífilos formadores de poros son cruciales para comprender el transporte por membranas.
- Controlar el ensamblaje de anfifiles es clave para afinar su función.
- Los anfifiles existentes a menudo forman poros a través de la dimerización.
Objetivo del estudio:
- Diseñar y sintetizar nuevos anfífilos formadores de poros con ensamblaje controlable.
- Para investigar el mecanismo de formación de poros (basado en monómeros vs. basado en dímeros).
- Para explorar las relaciones estructura-actividad de estos anfífilos.
Principales métodos:
- Síntesis de anfifiles derivados del ácido cólico, la lisina y la p-fenilenodiamina.
- Preparación de las dos capas lipídicas mediante el uso de 1-palmitoyl-2-oleoyl-2-sn-glycero-3-fosfocolina (POPC).
- Mediciones del transporte de iones de sodio (Na+) para evaluar la cinética de la formación de poros.
- Estudios de relaciones estructura-actividad centrados en la compacidad anfifila.
Principales resultados:
- Dos anfífilos, derivados del ácido cólico, la lisina y la p-fenilendiamina, forman poros como moléculas individuales.
- Los anfifiles análogos que carecen de una fracción rígida de 1,4-fenilenodiamida forman poros basados en dimeros.
- La evidencia cinética del transporte de Na+ apoya los mecanismos de formación de poros basados tanto en monómeros como en dímeros.
- La compacidad anfifila influye significativamente en la actividad de los formadores de poros basados en dímeros.
Conclusiones:
- La porción rígida de 1,4-fenilenodiamida es crítica para la formación de poros basados en monómeros.
- El diseño anfipilo puede controlar los mecanismos de formación de poros (monómero vs. dímero).
- Estos hallazgos abren posibilidades para desarrollar anfifiles con propiedades supramoleculares sintonizables para aplicaciones prácticas.
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