Fig. 2. (A) Fluorescence behaviors of the CHA-DNAzyme (c*/c), HCR-DNAzyme (b*/b), and CHA-HCR-DNAzyme (a*/a) systems with/without their corresponding initiators for 4 h. (B) Bar representation of the fluorescence spectra (λ = 520 nm) for the dual and triple amplifiers (note: as for the HCR-DNAzyme, “I” refers to “T”). (C) AFM characterization of the triggered CHA-HCR-DNAzyme biocircuits. Inset: cross-section height analysis of the generated dsDNA nanowires. (D) Native gel electrophoresis analysis of the intact CHA-HCR-DNAzyme system: lanes i to vi represent the CHA reactant, CHA product, HCR reactant, HCR product, CHA-HCR-DNAzyme reactant, and CHA-HCR-DNAzyme product, respectively.