Manufacturing of Microfluidic Devices with Interchangeable Commercial Fiber Optic Sensors

Area of Science:

• Microfluidics
• Sensor Technology
• Materials Science

Background:

• In situ measurements in microfluidics are vital for real-time monitoring but integrating sensors is challenging.
• Current methods for sensor integration are often complex, costly, and require specialized expertise.

Purpose of the Study:

• To develop an easy-to-implement method for integrating commercial fiber optic sensors into microfluidic devices.
• To demonstrate the performance of integrated pH and pressure sensors in a microfluidic environment.

Main Methods:

• Utilized custom 3D-printed connectors for reversible attachment of "off-the-shelf" pH and pressure sensors to a laser-fabricated glass microfluidic device.
• Performed experiments to evaluate sensor accuracy and connector performance under practical microfluidic conditions.

Main Results:

• 3D-printed connectors provided robust, watertight, and reversible sensor integration.
• Integrated pH sensors achieved accuracy of ±0.05 pH, while pressure sensors measured up to 140 mbar with < ±1.5 mbar uncertainty.
• Observed dynamic pressure changes and confirmed Darcy's law for fluid flow, enabling permeability determination.

Conclusions:

• The developed method offers a cost-effective and accessible solution for in situ sensing in microfluidic systems.
• This approach facilitates real-time monitoring and characterization of microfluidic processes and materials.