A bespoke reagent free amperometric chloride sensor for drinking water

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Environmental Science

Background:

• Chloride quantification is crucial for ensuring drinking water safety and quality.
• Existing methods for chloride analysis can be complex, time-consuming, or require additional reagents.
• There is a need for rapid, simple, and accurate chloride sensing methods suitable for field or on-site applications.

Purpose of the Study:

• To develop and validate a bespoke, reagent-free electrochemical method for chloride quantification in mineral water.
• To establish a simple and accurate chloride sensor that eliminates the need for added electrolytes.
• To demonstrate the sensor's applicability and reliability for real-world water quality monitoring.

Main Methods:

• Electrochemical voltammetry was employed using a silver macro disc electrode.
• The method involved an initial oxygen reduction step for electrode cleaning and activation, followed by silver chloride formation and stripping.
• No mechanical polishing or external electrolyte addition was required.

Main Results:

• A linear correlation was established between silver chloride stripping peak currents and chloride concentrations.
• The sensor demonstrated accurate quantification within a concentration range of 0.4 mM to 3.2 mM.
• Excellent agreement was observed when analyzing chloride levels in two different mineral water samples compared to independent analysis.

Conclusions:

• The developed electrochemical method provides a rapid, simple, and reagent-free approach for accurate chloride determination in mineral water.
• The sensor's ability to self-clean and activate the electrode surface enhances reproducibility and simplifies operation.
• This technology holds promise for effective drinking water quality control and monitoring.