Electrochemical aptasensor based on potassium ion-triggered DNA conformation transition and self-assembly on electrode

Herein, a novel electrochemical biosensor for sensitive and selective detection of potassium ion (K+) is developed. Aptamer sequence against K+ is integrated in a DNA probe for specific recognition, which initiates DNA conformation transition and activates thiol group for effective self-assembly of the DNA probe on gold electrode surface. By analyzing electrochemical signals labelled on the DNA probe, K+ level can be facilely determined. The proposed electrochemical aptasensor has plain sensing principle and simple operation. Moreover, excellent analytical performances are achieved owing to the ingenious design, which may also inspire the development of the other electrochemical biosensors.