Thiol-based chemically modified carbon screen-printed electrode for simultaneous quantification of trace level Pb(II)...

Area of Science:

• Electrochemistry
• Analytical Chemistry
• Materials Science

Background:

• Heavy metal contamination (Pb(II), Cd(II)) poses significant environmental and health risks.
• Accurate and sensitive detection methods are crucial for monitoring water quality.
• Existing methods may lack selectivity or require complex procedures.

Purpose of the Study:

• To develop a novel electrochemical sensor for simultaneous determination of Pb(II) and Cd(II).
• To utilize diazonium coupling and covalent attachment of cysteamine on screen-printed carbon electrodes.
• To achieve enhanced sensitivity, selectivity, and stability for heavy metal detection.

Main Methods:

• Fabrication of a modified screen-printed carbon electrode (SPCE) via electro-grafting of 4-carboxyphenyl diazonium salt and covalent attachment of cysteamine.
• Simultaneous quantification of Pb(II) and Cd(II) using square wave anodic stripping voltammetry (SWASV).
• Optimization of experimental conditions and validation using spiked water samples.

Main Results:

• The developed sensor (Cyst/4-CP/SPCE) demonstrated high sensitivity and selectivity for Pb(II) and Cd(II) without interference.
• Achieved a wide linear range of 0.01 µM to 0.7 µM.
• Obtained low limits of detection (LOD): 0.882 nM for Cd(II) and 0.65 nM for Pb(II).
• Demonstrated good stability, reproducibility, and successful application in real water samples with results comparable to ICP-AES.

Conclusions:

• The novel electrochemical sensor offers a reliable and efficient platform for simultaneous detection of Pb(II) and Cd(II).
• The sensor's performance in real-world samples highlights its practical applicability for environmental monitoring.
• This approach provides a sensitive and selective method for heavy metal analysis in aqueous matrices.