Xu Ting, Cao Li, An Shuhao, Liu Xiaowei, Li Zhen, Lai Zhiping
Center of Excellence for Renewable Energy and Storage Technologies (CREST), Division of Physical Science and Engineering, 4700 King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia.
Nat Commun. 2025 Aug 21;16(1):7803. doi: 10.1038/s41467-025-63247-y.
The separation of amino acids from complex mixtures remains an essential yet multi-step, energy-intensive process. Membrane separation technology offers a more energy-efficient alternative, but its effectiveness relies on achieving highly precise molecular recognition. Here, we report a homochiral covalent organic framework (COF) membrane with ordered ultra-microporous pore structures for targeted extraction of specific enantiomer from amino acid mixtures. Benefiting from its high crystallinity and ultra-microporous chiral channels, the membrane exhibits both excellent permeability and enantioselectivity. A combination of experimental results, density functional theory calculations, and molecular dynamics simulations reveal a retarded transport mechanism, wherein stronger interactions between L-enantiomers and the homochiral pores hinder their transmembrane diffusion. We further demonstrate a two-stage cascade membrane process to simultaneously fractionate and enantioseparate amino acid mixtures, achieving near pure (99.5%) D-threonine from an eight-component protein hydrolysis complex. This study offers a promising and sustainable membrane-based solution for efficient amino acid purification.
从复杂混合物中分离氨基酸仍然是一个必不可少但却多步骤、能源密集型的过程。膜分离技术提供了一种更节能的替代方案，但其有效性依赖于实现高度精确的分子识别。在此，我们报道了一种具有有序超微孔结构的同手性共价有机框架（COF）膜，用于从氨基酸混合物中靶向提取特定对映体。受益于其高结晶度和超微孔手性通道，该膜表现出优异的渗透性和对映选择性。实验结果、密度泛函理论计算和分子动力学模拟相结合揭示了一种阻滞传输机制，其中L-对映体与同手性孔之间更强的相互作用阻碍了它们的跨膜扩散。我们进一步展示了一种两级级联膜过程，以同时对氨基酸混合物进行分馏和对映体分离，从八组分蛋白质水解复合物中获得了近乎纯的（99.5%）D-苏氨酸。这项研究为高效氨基酸纯化提供了一种有前景的、可持续的基于膜的解决方案。
