A bio-inspired potassium and pH responsive double-gated nanochannel

Bio-inspired nanochannels have emerged as an interface to mimic the functionalities of biological nanochannels. One remaining challenge is to develop double-gated nanochannels with dual response, which can regulate the ion transport direction by alternately opening and closing the two gates. In this work, a bio-inspired potassium and pH responsive double-gated nanosystem is presented, constructed through immobilizing C-quadruplex and G-quadruplex DNA molecules onto the top and bottom tip side of a cigar-shaped nanochannel, respectively. It is demonstrated that the two gates of the nanochannel can be opened and closed alternately/simultaneously. This phenomenon results from the attached DNA conformational transition caused by adjusting the concentrations of potassium ion and proton. This design is believed to be the first example of dual-responsive double-gated nanosystem, and paves a new way to investigate more intelligent bio-inspired nanofluidic system.