DNA Nanobiosensors: An Outlook on Signal Readout Strategies

Figure 1

Concepts used in biosensing platforms. (a, b) Sequence-specific DNA hybridization in a duplex and stem-loop configuration, (c) triplex formation under acidic conditions, (d) i-motif formation under acidic conditions by C-rich DNA strands, (e) poly-dA helix formation under acidic conditions by poly-A strands, (f) G-quadruplex formation in the presence of K⁺ or Na⁺, (g) aptamer reconfiguration in the presence of specific ligands, and (h) toehold-based strand displacement.

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