Peptide-Appended Hybrid[4]Arenes Are Artificial Water Channels with High Permeability and Selectivity

The development of new artificial water channels that mimic aquaporins has gained increased interest in recent years, particularly due to the ever increasing global demands on pure water supply. Criteria for development of advanced water channels can be considered as: 1) water permeability, 2) selectivity and 3) feasibility of commercialization. Several candidates have been suggested but none of them have substantially satisfied the above standards, including aquaporin proteins, carbon nanotubes and current synthetic water channels. Here, we propose new version of artificial water channel, peptide-appended hybrid[4]arenes (PAH[4]). Our experimental data showed PAH[4]’s single channel water permeability at 2.3(±1.1)×10⁹ water molecules per second which is comparable with those of aquaporin’s (0.34~4.03×10⁹ water molecules per second), in addition to significant sodium chloride rejection (~100%). Based on these results, PAH[4] is highly expected to have an ideal pore structure in terms of water permeability and monovalent ion selectivity. Furthermore, since this artificial channels has outstanding compatibility with various organic solvents, PAH[4] is believed to meet above mentioned qualifications for a promising candidate to develop reverse osmosis membranes based on artificial water channels.