A Label-Free Electrochemical Aptasensor for the Analysis of The Potassium Ion

Abstract

Herein, a simple and novel electrochemical method for the detection of potassium ions (K⁺) was developed. In the presence of potassium ions, the potassium ions aptamer will form a G-quadruplex complex. Thus, further addition of hemin in the presence of potassium ions will lead to the formation of a recombined G-quadruplex. Then the electroactive label, hemin, will give an electrochemical response. The linear range of the method covered a large variation of K⁺ concentration from 0.1 nM to 0.1 μM and the detection limit of 0.1 nM was obtained. Moreover, this assay was able to detect K⁺ with high selectivity and had great potential applications.

Keywords:

• potassium ions
• electrochemistry
• ICU
• G-quadruplex