Inorganic arsenic speciation by differential pulse anodic stripping voltammetry using thoria nanoparticles-carbon...

Area of Science:

• Electrochemistry
• Analytical Chemistry
• Materials Science

Background:

• Arsenic contamination in water poses significant health risks.
• Accurate and sensitive methods for arsenic detection are crucial for environmental safety.
• Nanomaterials offer unique properties for developing advanced electrochemical sensors.

Purpose of the Study:

• To develop and evaluate a novel anodic stripping voltammetric method for direct arsenic determination in water samples.
• To assess the performance of thoria (ThO2) nanoparticles-carbon paste electrodes for arsenic analysis.
• To investigate the influence of common interfering ions on the electrochemical response of arsenic.

Main Methods:

• Fabrication of thoria (ThO2) nanoparticles-carbon paste electrodes.
• Application of anodic stripping voltammetry (ASV) for arsenic detection.
• Assay of the effect of Ag(I), Cu(II), Hg(II), Sb(III), and Se(IV) ions on arsenic detection.
• Validation of the method using certified reference materials (trace elements in natural water, water, and coal fly ash).

Main Results:

• The developed method demonstrated rapid analysis with improved analytical characteristics.
• High selectivity and good repeatability (3.4%) were achieved at low arsenite concentrations.
• A low limit of detection (0.1 μg L⁻¹) and high sensitivity (0.54 μA μg⁻¹ L) were obtained.
• The method was successfully applied to determine arsenic in certified reference materials.

Conclusions:

• Thoria nanoparticles-carbon paste electrodes provide a promising platform for sensitive and selective arsenic determination in water.
• The developed anodic stripping voltammetric method offers a reliable tool for environmental arsenic monitoring.
• The method exhibits excellent analytical capabilities for direct arsenic quantification in complex matrices.