Evaluation of a same-metal PCB-based three-electrode system via impedance studies using potassium ferricyanide

Area of Science:

• Electrochemistry
• Analytical Chemistry
• Materials Science

Background:

• Conventional electrochemical impedance spectroscopy (EIS) systems require expensive electrodes and large analyte volumes.
• Miniaturization and cost-effectiveness are key challenges in developing portable electrochemical sensors.

Purpose of the Study:

• To develop and validate a novel, miniaturized, same-metal printed circuit board (PCB)-based three-electrode system for EIS.
• To demonstrate the system's capability for analyzing trace amounts of analytes with high accuracy and sensitivity.

Main Methods:

• Fabrication of a miniaturized PCB-based three-electrode sensor.
• Characterization using electrochemical impedance spectroscopy with potassium ferricyanide as a redox probe.
• Analysis of impedance data using Nyquist and Bode plots and circuit fitting to a Randles cell model.

Main Results:

• The PCB-based three-electrode system successfully acquired EIS data using only 10-20 μL of analyte.
• The system demonstrated superior repeatability, reproducibility, and consistency across different instruments.
• EIS data fitted well to a simplified Randles cell model, enabling accurate quantification of potassium ferricyanide concentrations.

Conclusions:

• The novel same-metal PCB-based three-electrode sensor is a cost-effective and sensitive platform for EIS analysis.
• This system is suitable for the accurate detection of trace analytes, overcoming limitations of conventional methods.