Hand-held microanalytical instrument for chip-based electrophoretic separations of proteins

Area of Science:

• Analytical Chemistry
• Biotechnology
• Microfluidics

Background:

• Developing portable analytical instruments is crucial for on-site biomolecule detection.
• Existing methods often lack the sensitivity or speed required for rapid analysis.
• Microchip-based systems offer miniaturization and potential for high-throughput analysis.

Purpose of the Study:

• To design, fabricate, and demonstrate a hand-held microchip analytical instrument (muChemLab).
• To enable detection and identification of proteins and other biomolecules.
• To achieve high sensitivity and reproducibility in microchip-based separations.

Main Methods:

• A modular system (muChemLab) with interchangeable fluid cartridges and a microfluidic chip.
• Utilized laser-induced fluorescence detection for sensitive analyte identification.
• Employed programmable high-voltage power supplies for controlled separations.

Main Results:

• Achieved picomolar detection sensitivity for fluorescent dyes and nanomolar sensitivity for labeled proteins.
• Demonstrated significantly improved migration time reproducibility (0.5-1%) under constant current control compared to constant voltage control (2-8%).
• The modular design facilitated rapid assembly, troubleshooting, and sample analysis.

Conclusions:

• The muChemLab system provides a reliable and flexible platform for portable biomolecule analysis.
• Constant current control enhances the reproducibility of microchip electrophoresis separations.
• This technology advances the field of on-site analytical instrumentation for biological samples.