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El huésped-[2]rotaxanos como agentes de transporte celular
Vadims Dvornikovs1, Brian E House, Marcia Kaetzel
1Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, USA.
Journal of the American Chemical Society
|July 3, 2003
Resumen
Los rotaxanos anfitrión-[2], con un anillo de éter dibenzo-24-corona-8, actúan como agentes de transporte celular efectivos. Se unen eficientemente a los aminoácidos y fluoróforos, facilitando la captación celular, incluido el transporte nuclear.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Biología Química Biología química.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los rotaxanos anfitrión-[2] están diseñados como estructuras supramoleculares con aplicaciones potenciales en el transporte molecular.
- Las fracciones de éter y ciclófano de dibenzo-24-corona-8 (DB24C8) son componentes clave que influyen en las interacciones huésped-huésped.
- Comprender las afinidades de unión y las capacidades de transporte de estos rotaxanos es crucial para su desarrollo.
Objetivo del estudio:
- Investigar las afinidades de unión de los rotaxanos huésped-[2] con varios huéspedes en diferentes sistemas de disolventes.
- Para evaluar la eficiencia del transporte celular de estos rotaxanos para moléculas biológicamente relevantes.
- Para comparar las capacidades de transporte de diferentes arquitecturas de rotaxano.
Principales métodos:
- Síntesis y caracterización de rotaxanos huésped-[2] con grupos ciclófanos o aromáticos bloqueadores de hendiduras.
- Determinación espectroscópica de las constantes de asociación (K(A)) para la unión del huésped en tampón acuoso, DMSO y sistemas de disolventes mixtos.
- Estudios de captación celular utilizando huéspedes con etiqueta fluorescente y células COS-7 para evaluar la eficiencia del transporte.
Principales resultados:
- Los rotaxanos anfitrión-[2] exhiben fuertes constantes de asociación (10^4 a 10^5 M^-1) para los huéspedes pépticos y los fluoróforos en los disolventes probados.
- La arquitectura de rotaxano mejora la unión del huésped en comparación con el componente de ciclófano solo.
- El ciclofano-[2]rotaxano 1 transporta eficientemente la fluoresceína y un inhibidor de la fluoresceína-PKC a las células COS-7, incluido el núcleo.
- El cleft-[2]rotaxano 2 muestra un transporte de fluoresceína menos eficiente a pesar de una afinidad de unión similar, lo que indica una entrega celular dependiente de la arquitectura.
Conclusiones:
- Los rotaxanos anfitrión-[2] son transportadores moleculares efectivos capaces de unirse a diversos huéspedes con alta afinidad.
- La estructura del rotaxano es ventajosa para el reconocimiento molecular y la unión.
- La arquitectura específica del rotaxano influye significativamente en la eficiencia de absorción celular, destacando la importancia del diseño estructural para una entrega dirigida.
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