Electrogenerated Chemiluminescence for Chronopotentiometric Sensors

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Chemiluminescence

Background:

• Chronopotentiometry is a technique used to measure potential changes over time.
• Electrogenerated chemiluminescence (ECL) offers sensitive detection methods.
• Integrating these techniques can enhance sensor capabilities.

Purpose of the Study:

• To develop a general strategy for reading out chronopotentiometric sensors using ECL.
• To establish a correlation between chronopotentiometric potentials and ECL signals.
• To demonstrate the method's applicability for analyte detection.

Main Methods:

• Utilizing potentials from chronopotentiometry to control ECL in a separate compartment.
• Employing a three-electrode cell for analyte concentration monitoring.
• Using the luminol-hydrogen peroxide system for ECL generation.
• Theoretical simulations and experimental validation with ferro/ferricyanide and carbonate alkalinity detection.

Main Results:

• Theoretical simulations confirmed the feasibility of the approach.
• A linear relationship was observed between analyte concentration and the square root of sampled time.
• The method successfully detected ferrocyanide (0.70–4.81 mM) and carbonate alkalinity (0.06–0.62 mM).
• Visual detection of carbonate alkalinity in real samples (river water, mineral water) was demonstrated.

Conclusions:

• The developed strategy provides a novel method for chronopotentiometric sensor readout via ECL.
• The technique offers a sensitive and potentially visual detection method for various analytes.
• This integration expands the toolkit for electrochemical sensing and analysis.