Biological membranes are ideal for separations as they provide high permeability while maintaining high solute selectivity due to the presence of specialized membrane protein (MP) channels. However, successful integration of MPs into manufactured membranes has remained a significant challenge. Here, we demonstrate a two-hour organic solvent method to develop 2D crystals and nanosheets of highly packed pore-forming MPs in block copolymers (BCPs). We then integrate these hybrid materials into scalable MP-BCP biomimetic membranes. These MP-BCP nanosheet membranes maintain the molecular selectivity of the three types of β-barrel MP channels used, with pore sizes of 0.8 nm, 1.3 nm, and 1.5 nm. These biomimetic membranes demonstrate water permeability that is 20–1,000 times greater than that of commercial membranes and 1.5–45 times greater than that of the latest research membranes with comparable molecular exclusion ratings. This approach could provide high performance alternatives in the challenging sub-nanometre to few-nanometre size range.
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The data supporting the findings of this study are available within the article and its supplementary information files and available from the authors upon reasonable request.
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The authors acknowledge financial support from the National Science Foundation (NSF) CAREER grant (CBET-1552571), NSF grant CBET-1709522 and NSF grant CBET-1804836 to M.K. for this work. T.C. and E.D.G. acknowledge financial support from NSF DMR-1609417. The authors also thank M. Hazen and J. Cantolina for their help with cross-sectional sample preparation. We thank L. Movileanu for the kind gift of the plasmid for expressing the FhuA ΔC/Δ4L protein.
A.P. and M.G. are employed by Applied Biomimetic, which aims to commercialize biomimetic membranes similar to those presented in this Article.
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Tu, YM., Song, W., Ren, T. et al. Rapid fabrication of precise high-throughput filters from membrane protein nanosheets. Nat. Mater. 19, 347–354 (2020). https://doi.org/10.1038/s41563-019-0577-z
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