Smart DNA Hydrogel Integrated Nanochannels with High Ion Flux and Adjustable Selective Ionic Transport.

Nanochannels based on smart DNA hydrogels as stimulus-responsive architecture are presented for the first time. In contrast to other responsive molecules existing in the nanochannel in monolayer configurations, the DNA hydrogels are three-dimensional networks with space negative charges, the ion flux and rectification ratio are significantly enhanced. Upon cyclic treatment with K+ ions and crown ether, the DNA hydrogel states could be reversibly switched between less stiff and stiff networks, providing the gating mechanism of the nanochannel. Based on the architecture of DNA hydrogels and pH stimulus, cation or anion transport direction could be precisely controlled and multiple gating features are achieved. Meanwhile, G-quadruplex DNA in the hydrogels might be replaced by other stimulus-responsive DNA molecules, peptides, or proteins, and thus this work opens a new route for improving the functionalities of nanochannel by intelligent hydrogels.