Fig. 1.
(a) +5_17E Lead sensor design based on a temperature independent 8–17 DNAzyme.4d (b) Design of current lead sensor based on the GR-5 DNAzyme. Substrate (black) is 5′ functionalized with a FAM molecule and 3′ functionalized with a BHQ-1® quencher. The enzyme strand (green) is 3′ functionalized with a BHQ-1® quencher. In both sensors in (a) and (b), all sequences represent DNA, except the “rA” in the middle of the substrate which represents adenosine ribonucleotide. The secondary structures are predicted by mfold.11 (c) Schematic representation of the proposed catalytic beacon sensing mechanism.