Figure 2.

(dT)₂₁ E-DNA sensor does not show any significant nonspecific interactions with the gold electrode surface, double-strand DNA (dsDNA), and non-DNA-binding protein. (Top) A double-strand E-DNA sensor architecture is achieved by adding the complement, (dA)₂₁, and used to test the selectivity and specificity of the single-strand E-DNA sensor. No significant changes in the current signals are observed, which indicates that the sensors are specific to single strand DNA binding. (Bottom) To further test specificity, E-DNA sensors modified with (dT)₂₁ DNA probes are tested against a similarly sized protein biomolecule, thrombin (∼37 kDa), using the same experimental conditions. Again, no significant changes in the current signals are obtained, which strongly demonstrates a highly specific DNA-binding protein binding sensor response.