Bonded dimethylacrylamide as a permanent coating for capillary electrophoresis

Area of Science:

• Analytical Chemistry
• Separation Science
• Chromatography

Background:

• Capillary electrophoresis (CE) is a powerful separation technique.
• Capillary coatings are crucial for improving separation efficiency and stability in CE.
• Polydimethylacrylamide (PDMA) is a polymer with potential for capillary coating.

Purpose of the Study:

• To develop a method for coating capillaries with chemically bonded polydimethylacrylamide.
• To evaluate the properties and performance of these coated capillaries for CE applications.

Main Methods:

• Chemical bonding of polydimethylacrylamide to capillary inner surfaces.
• Evaluation of separation efficiency using cytochrome c.
• Assessment of electroosmotic flow (EOF) at different pH levels.
• Testing capillary stability at high pH.
• Demonstration of separation capabilities with various biomolecules.

Main Results:

• High separation efficiency achieved, with 1.2 x 10^6 theoretical plates/m for cytochrome c.
• Stable electroosmotic flow (EOF) observed, ranging from 10 x 10^-10 to 6 x 10^-10 m^2 V^-1 s^-1 at pH 8.0.
• Excellent capillary stability demonstrated, with over 150 runs possible at pH 10 without significant performance degradation.
• Successful separation of diverse analytes, including basic and acidic proteins, derivatized amino acids, and peptides.

Conclusions:

• Chemically bonded polydimethylacrylamide coatings provide a robust and efficient solution for capillary electrophoresis.
• The developed coated capillaries exhibit high separation performance and remarkable stability, making them suitable for complex biological sample analysis.