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Cuadros orgánicos covalentes con aperturas porosas de registro

Zhenjie Mu1, Yuhao Zhu1, Bixiao Li1

  • 1Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education, Advanced Technology Research Institute (Jinan), Frontiers Science Center for High Energy Material, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China.

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|March 8, 2022
PubMed
Resumen
Este resumen es generado por máquina.

Los investigadores desarrollaron nuevos marcos orgánicos covalentes (COF) con mesóporos uniformes de tamaño récord de hasta 10,0 nm. Estos materiales estables y cristalinos permiten la separación de grandes biomoléculas como la pepsina y protegen las enzimas.

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Área de la Ciencia:

  • Ciencias de los materiales
  • Química de los polímeros
  • Nanotecnología

Sus antecedentes:

  • Los materiales porosos con tamaños de poro ajustables son cruciales para la separación y protección molecular.
  • Los marcos orgánicos metálicos (MOF) y los marcos orgánicos covalentes (COF) existentes tienen limitaciones en el tamaño de la abertura de los poros, lo que dificulta el acceso de las moléculas grandes.
  • El logro de mesoporos uniformes y grandes en polímeros porosos cristalinos sigue siendo un desafío significativo.

Objetivo del estudio:

  • Construir nuevas estructuras orgánicas covalentes (COF) con aberturas mesopóricas prediseñadas para romper récords.
  • Superar las limitaciones de la interpenetración y la fragilidad estructural en la creación de COF de grandes poros.
  • Demostrar la utilidad de estos nuevos COF en aplicaciones prácticas que involucren a grandes biomoléculas.

Principales métodos:

  • Diseño y síntesis de nuevos bloques de construcción con rigidez conformacional mejorada, planaridad y polaridad local controlada.
  • Caracterización de los marcos orgánicos covalentes (COF) resultantes para la cristalinidad, la porosidad, la estabilidad y la distribución del tamaño de los poros.
  • Aplicación de los COF sintetizados en la separación de biomoléculas y en la protección enzimática.

Principales resultados:

  • Se sintetizó con éxito una serie de marcos orgánicos covalentes (COF) con valores de apertura de poros que oscilaban entre 7,7 y 10,0 nm, superando los registros anteriores.
  • Los COF obtenidos mostraron una alta cristalinidad, porosidad permanente, estabilidad estructural y apilamiento eclipsado.
  • Se ha demostrado la separación exitosa de la pepsina (aproximadamente 7 nm) de las mezclas brutas y la protección de la tirosinasa de la desnaturalización inducida por el calor.

Conclusiones:

  • La estrategia desarrollada permite la construcción de marcos orgánicos covalentes (COF) con mesóporos sin precedentes grandes y uniformes.
  • Estos nuevos COF ofrecen un potencial significativo para tecnologías avanzadas de separación y estabilización biomolecular.
  • Los hallazgos allanan el camino para diseñar materiales porosos de próxima generación para interacciones moleculares complejas.