Multiparametric optimization of a new high-sensitive and disposable mercury (II) electrochemical sensor

Area of Science:

• Electrochemistry
• Materials Science
• Environmental Science

Background:

• Mercury (II) is a toxic heavy metal pollutant.
• Accurate determination of mercury is crucial for environmental monitoring.
• Existing methods for mercury detection can be complex and time-consuming.

Purpose of the Study:

• To develop a sensitive and reliable electrochemical sensor for mercury (II) determination.
• To optimize sensor composition and measurement parameters for enhanced performance.
• To validate the sensor's applicability in real-world water samples.

Main Methods:

• Modification of screen-printed carbon electrodes (SPCE) with a polystyrene sulfonate-NiO-carbon nanopowder composite.
• Electrochemical measurements using differential pulse anodic stripping voltammetry (DPASV).
• Optimization of sensor and measurement conditions via multivariate experimental design (Plackett-Burman, Central Composite Design, Response Surface Methodology).

Main Results:

• The developed NiO-PSS-SPCE sensor demonstrated a very low limit of detection (0.021 μg L⁻¹).
• A linear response was observed over two concentration ranges: 0.05–2.0 μg L⁻¹ and 2.0–75 μg L⁻¹.
• The sensor was successfully applied for mercury determination in water samples.

Conclusions:

• The optimized electrochemical sensor provides a sensitive and effective method for mercury (II) detection.
• The NiO-PSS-SPCE composite material shows promise for developing advanced electrochemical sensors.
• This sensor offers a viable tool for environmental monitoring of mercury contamination.