Integration of two different sensing modes in an electrochemical DNA sensor for approximation of target mismatch location

We report for the first time an electrochemical DNA sensor that utilizes two different electroactive signaling species, methylene blue and ferrocene, simultaneously, functioning as “signal-off” and “signal-on” probes, respectively, for approximation of the mismatch location on the target DNA.

Graphical abstractAn electrochemical DNA sensor that utilizes two different electroactive signaling species, methylene blue and ferrocene, simultaneously, functioning as “signal-off” and “signal-on” probes, respectively, for approximation of the mismatch location on the target DNA.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch Highlights► The presence of target DNA produces a dramatic decrease in the MB current, accompanied by a substantial increase in the Fc current. ► MB and Fc show similar response kinetics. ► The sensor is capable of approximating the location of mismatches in the target DNA. ► The sensor performs robustly in 50% fetal calf serum. ► The concept of “multi-color” electrochemical biosensors is realized.