Automated square-wave anodic-stripping voltammetry with a flow-through cell and matrix exchange

Area of Science:

• Electroanalytical Chemistry
• Analytical Instrumentation
• Trace Metal Analysis

Background:

• Square-wave anodic-stripping voltammetry (SWASV) is a powerful technique for trace metal detection.
• Existing instrumentation may lack versatility in sample matrix handling and parameter control.
• Development of a highly sensitive and adaptable SWASV system is crucial for advanced environmental and chemical analysis.

Purpose of the Study:

• To describe a novel, extremely sensitive, and versatile instrument for square-wave anodic-stripping voltammetry.
• To demonstrate the instrument's capability to change solution matrices between deposition and stripping steps.
• To showcase the microcomputer-controlled system's flexibility in parameter adjustment for optimized trace metal analysis.

Main Methods:

• Development of a microcomputer-controlled instrument for square-wave anodic-stripping voltammetry.
• Incorporation of a flow-through cell allowing matrix changes between deposition and stripping.
• Utilization of a custom-built static mercury drop electrode.
• System control via microcomputer for adjustable square-wave parameters, scan potentials, deposition time, scan rate, sensitivity, and drop size.

Main Results:

• Demonstrated high sensitivity with calibration graphs for Cadmium (Cd) in the ranges 0.2-40 ng/ml and 0.1-1 ng/ml.
• Evaluated the reproducibility of the static mercury drop electrode.
• Successfully applied the method for Cd analysis in a sodium chloride (NaCl) sample, showcasing practical applicability.

Conclusions:

• The developed instrument offers exceptional sensitivity and versatility for SWASV.
• The flow-through cell and microcomputer control facilitate adaptable trace metal analysis.
• The system is a valuable tool for accurate quantification of trace metals in complex matrices.