Coupling Microdialysis Sampling to Microchip Electrophoresis in a Reversibly Sealed Device

Area of Science:

• Analytical Chemistry
• Biomedical Engineering
• Microfluidics

Background:

• Microdialysis sampling and microchip electrophoresis are powerful analytical techniques.
• Integrating these techniques offers enhanced analytical capabilities.
• Previous interfaces faced challenges with reusability and direct coupling.

Purpose of the Study:

• To fabricate and characterize a novel, reversibly sealed microchip device.
• To couple microdialysis sampling directly to microchip electrophoresis.
• To assess the device's suitability for repeated use and reproducible analysis.

Main Methods:

• Fabrication of a poly(dimethylsiloxane)-based microchip device.
• Integration of pneumatic valves for fluidic control.
• Direct interfacing of microdialysis probe tubing with the microchip.
• Fluorescence detection for characterization and reproducibility assessment.
• Analysis of derivatized amino acids.

Main Results:

• Demonstrated successful coupling of microdialysis sampling to microchip electrophoresis.
• Characterized the device for injection reproducibility using fluorescence detection.
• Determined a system concentration response lag time of 170 seconds.
• Successfully performed electrophoretic separation of derivatized amino acids.

Conclusions:

• The developed microchip device offers a reusable and efficient interface for coupled microdialysis and microchip electrophoresis.
• The integrated pneumatic valves facilitate seamless sample transfer and analysis.
• This technology holds promise for in-situ monitoring and complex sample analysis.