Poly(ethylene glycol)-coated microfluidic devices for chip electrophoresis

Area of Science:

• Analytical Chemistry
• Materials Science
• Biotechnology

Background:

• Microfluidic chips are widely used for separations.
• Surface modification is crucial for improving chip performance.
• Uncoated glass chips suffer from electroosmotic flow and analyte adsorption.

Purpose of the Study:

• To develop a durable surface modification strategy for microfluidic glass chips.
• To improve the performance of microchip electrophoresis (ME) by reducing electroosmotic flow (EOF) and analyte adsorption.
• To evaluate the effectiveness of poly(ethylene glycol) (PEG) coating for ME applications.

Main Methods:

• Durable surface modification of microfluidic glass chips using poly(ethylene glycol) (PEG-1M-100).
• Application of PEG-coated chips in microchip electrophoresis.
• Electrophoretic separation of FITC-labelled amines, amino acids, native proteins, and chiral compounds.

Main Results:

• PEG coating effectively suppressed electroosmotic flow (EOF).
• Analyte adsorption to the chip surface was significantly reduced.
• High stability and reproducibility were achieved, with migration time RSD < 2%.
• Superior performance compared to uncoated microchips in various electrophoretic applications.

Conclusions:

• Durable PEG coating is a highly effective strategy for modifying microfluidic chip surfaces.
• PEG-coated chips offer enhanced performance and stability for microchip electrophoresis.
• This method is suitable for a wide range of analytes, including chiral separations.