Ion-Tuned DNA/Ag Fluorescent Nanoclusters As Versatile Logic Device

A novel kind of versatile logic device has been constructed utilizing ion-tuned DNA/Ag fluorescent nanoclusters, with K(+) and H(+) as two Inputs. A well-chosen hairpin DNA with a poly-C loop serves as the template for synthesizing two species of Ag nanoclusters. Several G-tracts and C-tracts on its two terminals enable the hairpin DNA to convert Into the G-quadruplex and/or i-motif structures upon input of K(+) and H(+). Such a structural change remarkably influences the spectral behaviors of Ag nanoclusters. In particular, different species of Ag nanoclusters have distinct. fluorescence responses to the input of K(+) and H(+). These unique features of DNA/Ag nanoclusters enable multiple logic operations via multichannel fluorescence output, indicating the versatility as a.. molecular logic device. By altering the specific sequence of the hairpin DNA, more logic gates can be constructed utilizing Ag nanoclusters.