A reversible metal ion fueled DNA three-way junction molecular device for turn-on and -off fluorescence detection of mercury ions (II) and biothiols respectively with high selectivity and sensitivity

We constructed a reversible molecular device in the nanoscale based on a DNA three-way junction (3WJ) fueled by Hg2+ binding and sequestration. It is highly responsive to external stimuli, which brings about optically detectable global structural changes. Such a DNA device can serve as a novel turn-on and -off fluorescent sensor for Hg2+ and biothiol detection with high selectivity and sensitivity.