Intermediate-Layer-Free Solid-Contact Ion-Selective Electrodes on Gold Microelectrode Arrays: A New Approach for...

Area of Science:

• Electrochemistry
• Analytical Chemistry
• Materials Science

Background:

• Conventional solid-contact ion-selective electrodes often require intermediate layers, complicating fabrication and potentially affecting performance.
• Developing simplified yet effective electrode designs is crucial for advancing sensor technology.

Purpose of the Study:

• To develop a new universal construction for intermediate-layer-free solid-contact ion-selective electrodes.
• To investigate the electrochemical performance of ion-selective electrodes utilizing a novel microelectrode array inner electrode.

Main Methods:

• Fabrication of ion-selective electrodes using a microelectrode array (e.g., gold microelectrode array - GMA) as the inner electrode, eliminating the need for intermediate layers.
• Testing with potassium-ion-sensitive (valinomycin) and nitrate-ion-sensitive (tridodecyldimethylammonium nitrate) membranes.
• Comparative analysis of electrode performance against conventional glassy carbon electrode (GCE) and gold electrode (GE) substrates.

Main Results:

• Ion-selective electrodes based on gold microelectrode arrays demonstrated excellent analytical parameters without intermediate layers.
• Significant improvements in stability, reversibility, and repeatability of electrode potential were observed compared to GCE and GE.
• The novel construction simplifies sensor preparation while maintaining high performance.

Conclusions:

• The microelectrode array offers a viable alternative to conventional intermediate layers in solid-contact ion-selective electrodes.
• This approach leads to simplified sensor fabrication and improved electrochemical performance, including enhanced stability and reproducibility.
• The developed universal construction holds promise for the development of next-generation ion-selective sensors.