Fig. 3

NO-driven ionic rectification and gate. a I−V responses of the OPD channel in the absence and presence of NO; b NO-driven ion gating ratio (Rg), which shows that the OPD channel was opened by NO; c LSCM observation of fluorescence signals of the OPD-modified nanochannel in the absence and presence of NO; d photographs of the water droplet shape on the PET films in the absence and presence of NO; e stability and switchability of the NO-responsive ionic gate. OPD o-phenylenediamine, LSCM laser-scanning confocal microscopy, PET polyethylene terephthalate