A three-dimensional micropillar electrode array-based microfluidic sensor for sensitive and stable voltammetric...

Area of Science:

• Electrochemistry
• Microfluidics
• Sensor Technology

Background:

• Phosphate detection is crucial for environmental monitoring.
• Existing methods may lack sensitivity or real-time capabilities.
• Microfluidic electrochemical sensors offer potential for improved performance.

Purpose of the Study:

• To design and fabricate a 3D gold micropillar array sensor.
• To optimize sensor geometry for enhanced electrochemical reactions.
• To evaluate the sensor's performance for phosphate detection.

Main Methods:

• Fabrication using microfluidic chip technology and electrochemical methods.
• Simulation analysis for optimizing geometrical parameters.
• Electrochemical measurements for sensitivity, LOD, linearity, stability, and interference tests.

Main Results:

• High sensitivity (-0.032 μA (μmol L^-1)^-1) and low LOD (0.7 μmol L^-1) for phosphate.
• Excellent linear relationship (R²=0.99) in the 5-50 μmol L^-1 range.
• High stability (1.3% RSD, 7% current drop over 30 days) and good interference resistance.

Conclusions:

• The developed sensor demonstrates excellent performance for phosphate detection.
• The sensor is suitable for real-time monitoring of phosphate in groundwater.
• Microfluidic electrochemical sensors show promise for environmental analysis.