Biomimetic Selective Ion Transport through Graphene Oxide Membranes Functionalized with Ion Recognizable Peptides

Membranes that differentiate ions are being actively developed to meet the needs in separation, sensing, biomedical and water treatment technologies. Biomimetic approaches that combine bio-inspired functional molecules with solid state supports offer a great potential of imitating the functions and principles of biological ion channels. Here we report the design and fabrication of biomimetic graphene oxide (GO) based membranes functionalized by a peptide motif with ion recognizable capability for selective ion transport. The peptide with selective ion binding affinity is adopted as an ion selective filter and anchored on GO surface. The resulting GO based membranes show remarkable ion selectivity toward the specific ion of interest for the transport across the membranes as in the biological ion channels. Ion recognition capability of a peptide motif successfully translates into ion specificity for selective transport. This study provides a new avenue for developing artificial ion channels by synergistic combination of biomimetic recognition chemistry with a novel nanoplatform such as GO.