Sequential injection analysis of thiocyanate ions using a microfluidic polymer chip with an embedded ion-selective...

Area of Science:

• Analytical Chemistry
• Microfluidics
• Electrochemistry

Background:

• Thiocyanate (SCN-) ion determination is crucial for various applications, including clinical diagnostics and environmental monitoring.
• Existing methods for SCN- detection can be complex or time-consuming.

Purpose of the Study:

• To develop a novel sequential injection analysis (SIA) system for efficient SCN- ion determination.
• To integrate a microfluidic polymer chip with an embedded SCN- ion-selective electrode (SCN(-)-ISE) for sensitive detection.

Main Methods:

• A sequential injection analysis (SIA) system was designed and optimized.
• A microfluidic polymer chip featuring an integrated SCN(-)-ISE was employed as the detector.
• The system's performance was evaluated using standard SCN- solutions.

Main Results:

• The developed SIA system demonstrated a good linear relationship between peak heights and logarithmic SCN- concentrations (1.0 × 10(-5) to 1.0 × 10(-1) mol dm(-3)).
• A Nernstian slope of 59.4 ± 3.8 mV decade(-1) was achieved, indicating reliable electrode performance.
• The system achieved a sample throughput of approximately 12 samples per hour.

Conclusions:

• The proposed SIA system offers a sensitive and efficient method for SCN- ion determination.
• The system's applicability was successfully demonstrated through the analysis of SCN- levels in human saliva samples.
• This microfluidic-based approach provides a promising platform for rapid SCN- analysis.