Centre for Advanced 2D Materials, National University of Singapore, Singapore, Singapore.
Materials Science and Engineering, National University of Singapore, Singapore, Singapore.
Nat Nanotechnol. 2021 Feb;16(2):174-180. doi: 10.1038/s41565-020-00795-y. Epub 2020 Nov 9.
Membranes are ubiquitous in nature with primary functions that include adaptive filtering and selective transport of chemical/molecular species. Being critical to cellular functions, they are also fundamental in many areas of science and technology. Of particular importance are the adaptive and programmable membranes that can change their permeability or selectivity depending on the environment. Here, we explore implementation of such biological functions in artificial membranes and demonstrate two-dimensional self-assembled heterostructures of graphene oxide and polyamine macromolecules, forming a network of ionic channels that exhibit regulated permeability of water and monovalent ions. This permeability can be tuned by a change of pH or the presence of certain ions. Unlike traditional membranes, the regulation mechanism reported here relies on specific interactions between the membranes' internal components and ions. This allows fabrication of membranes with programmable, predetermined permeability and selectivity, governed by the choice of components, their conformation and their charging state.
膜在自然界中无处不在，其主要功能包括适应性过滤和化学/分子物质的选择性运输。由于膜对细胞功能至关重要，因此在许多科学和技术领域也具有基础性作用。特别重要的是自适应和可编程膜，它们可以根据环境改变其渗透性或选择性。在这里，我们探索了在人工膜中实现这些生物功能，并展示了氧化石墨烯和聚胺大分子的二维自组装杂化结构，形成了离子通道网络，表现出对水和单价离子的可调节渗透性。这种渗透性可以通过 pH 值的变化或特定离子的存在来调节。与传统膜不同，这里报道的调节机制依赖于膜内部成分与离子之间的特定相互作用。这使得可以制造具有可编程、预定渗透性和选择性的膜，其渗透性和选择性由组件的选择、构象及其荷电状态来控制。
