A High-Fidelity Electrochemical Platform Based on Au–Se Interface for Biological Detection

Gold (Au) electrodes are one of the most ideal electrodes and are extensively used to construct electrochemical biological detection platforms. The electrode–molecule interface between the Au electrode and biomolecules is critical to the stability and efficiency of the detection platform. However, traditional Au–sulfur (Au–S) interfaces experience distortion due to high levels of glutathione (GSH) and other biological thiols in biological samples as well as a high charge barrier when electrons are injected into the biomolecule from the Au electrode. In view of the higher bonding energy of Au–selenium (Au–Se) bonds than those of Au–S bonds and the elevated Fermi energy of the Au electrodes when Au–Se bonds are formed instead of Au–S bonds at the interface between the electrodes and molecules, we establish a new type of electrochemical platform based on the Au–Se interface (Au–Se electrochemical platform) for high-fidelity biological detection. Compared with that of the electrochemical platform based on the Au–S interface (Au–S electrochemical platform), the Au–Se electrochemical platform shows a higher charge transfer rate and excellent stability in millimolar levels of GSH. The Au–Se electrochemical platform supplies an ideal solution for accurate biological detection and has great potential in biomedical detection applications.