Quaternized celluloses as new dynamic coatings in capillary electrophoresis for basic protein separation

Area of Science:

• Analytical Chemistry
• Separation Science
• Materials Science

Background:

• Capillary electrophoresis (CE) often faces challenges with the adsorption of basic proteins onto fused silica capillaries.
• Achieving stable and reversed electroosmotic flow (EOF) is crucial for efficient separation of analytes, especially basic proteins.

Purpose of the Study:

• To investigate quaternized celluloses (QCs) as novel dynamic coatings for capillary electrophoresis.
• To evaluate the impact of QC molecular parameters and buffer pH on EOF and separation performance.
• To demonstrate the effectiveness of QC coatings in separating basic proteins and analyzing biosamples.

Main Methods:

• Homogeneous synthesis of quaternized celluloses (QCs) in NaOH/urea aqueous solutions.
• Coating fused silica capillaries with QCs at low concentrations (3 μg/mL).
• Investigating EOF mobility and separation of basic proteins under varying QC properties and buffer pH.

Main Results:

• Stable reversed EOF was achieved with QC coatings at concentrations as low as 3 μg/mL.
• QC coatings drastically reduced analysis time and improved separation performance across a broad pH range.
• Baseline separation of five basic proteins was achieved even at pH 8.0, demonstrating minimized protein adsorption.

Conclusions:

• Quaternized celluloses are effective dynamic coatings for capillary electrophoresis.
• QC coatings enhance separation efficiency and reproducibility for basic proteins by preventing adsorption.
• The developed QC coatings show promise for biosample analysis in CE.