Electrochemical velocimetry on centrifugal microfluidic platforms

Area of Science:

• Microfluidics
• Electrochemistry
• Analytical Chemistry

Background:

• Centrifugal microfluidic platforms are increasingly used in various applications.
• Real-time flow monitoring is crucial for controlling and optimizing microfluidic processes.
• Existing flow monitoring techniques may be limited in rotating microfluidic systems.

Purpose of the Study:

• To introduce electrochemical velocimetry as a novel method for real-time flow monitoring in centrifugal microfluidics.
• To demonstrate the simplicity and effectiveness of the electrochemical velocimetry setup.
• To validate the accuracy of electrochemical velocimetry against theoretical and optical measurements.

Main Methods:

• Embedding miniaturized electrodes within microfluidic channels on a rotating disc.
• Connecting electrodes to a peripheral potentiostat for electrochemical measurements.
• Utilizing electrochemical signals to determine on-disc flow rates.

Main Results:

• Electrochemical velocimetry provided accurate real-time flow rate measurements on centrifugal microfluidic devices.
• Measured flow rates showed good agreement with theoretical predictions and optical measurements.
• The technique successfully captured dynamic processes like droplet formation and release, providing data on frequency and volume.

Conclusions:

• Electrochemical velocimetry is a powerful and previously unavailable tool for real-time flow monitoring in centrifugal microfluidics.
• This technique enhances the capabilities of rotating microfluidic systems by enabling precise flow control and analysis.
• The presented method facilitates a deeper understanding of fluid dynamics in microfluidic applications.