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Exclusión estérica completa de iones y transporte de protones a través del agua confinada en una sola capa
K Gopinadhan1,2,3, S Hu2, A Esfandiar1,4
1School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.
Science (New York, N.Y.)
|January 12, 2019
Resumen
Los investigadores crearon capilares a escala atómica para el transporte de agua altamente selectivo. Estas estructuras permiten el paso de agua y protones, pero bloquean los iones, imitando las acuaporinas naturales para una filtración avanzada.
Área de la Ciencia:
- Ciencias de los materiales
- Nanotecnología
- Química Física
Sus antecedentes:
- Imitar los canales de proteínas naturales como las acuaporinas para la filtración artificial del agua ha sido un objetivo de larga data.
- Los poros y capilares de nanoescala artificiales existentes son generalmente más grandes que los canales biológicos, lo que limita su eficiencia.
- Lograr una precisión a nivel atómico en estructuras artificiales para el transporte molecular sigue siendo un desafío importante.
Objetivo del estudio:
- Diseñar capilares artificiales con dimensiones a escala atómica (algunos angstroms) para un control preciso del transporte molecular.
- Para investigar la permeación selectiva del agua, los iones (Na+, Cl-), y los protones (H+) a través de estas hendiduras a escala de angstrom.
- Para avanzar en la comprensión de los mecanismos de transporte molecular a escala atómica.
Principales métodos:
- Fabricación de capilares mediante la extracción de un solo plano atómico de cristales a granel, creando hendiduras bidimensionales.
- Medición experimental de la permeación de agua, iones (Na+, Cl-) y protones (H+) a través de los capilares a nivel de angstrom.
- Análisis de las propiedades de transporte a escala atómica.
Principales resultados:
- El agua penetra rápidamente a través de los capilares a escala de angstrom con una resistencia mínima.
- No se detectó permeación para los iones de sodio (Na+) y cloruro (Cl-) hidratados, incluso en cantidades pequeñas.
- Se demostró la difusión de protones (H+) a través del agua de la monocapa dentro de los capilares.
Conclusiones:
- Los capilares a escala atómica se pueden diseñar para lograr un transporte altamente selectivo, permitiendo el paso de agua y protones mientras se rechazan los iones.
- Estos hallazgos proporcionan una nueva plataforma para estudiar y controlar el transporte molecular en el límite último de las dimensiones atómicas.
- Los resultados ofrecen información sobre los principios fundamentales de filtración y transporte relevantes tanto para los sistemas artificiales como para los canales biológicos.
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