Monolithic column functionalized with quinine derivative for anion-exchange capillary electrochromatography

Area of Science:

• Analytical Chemistry
• Separation Science
• Polymer Chemistry

Background:

• Capillary electrochromatography (CEC) is a powerful separation technique.
• Development of novel stationary phases is crucial for enhancing CEC performance.
• Anion-exchange materials are valuable for separating acidic analytes.

Purpose of the Study:

• To synthesize and characterize a novel anion-exchange organic polymer monolithic column.
• To evaluate the suitability of this column for the separation of acidic compounds using CEC.
• To introduce N-benzylquininium as a strong anion-exchange functional group.

Main Methods:

• In situ copolymerization of N-benzylquininium chloride and acrylamide to form a monolithic column.
• Capillary electrochromatography (CEC) for the separation of eight acidic compounds.
• Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FT-IR) for characterization.
• Evaluation of electroosmotic flow (EOF) and column efficiency.

Main Results:

• A novel anion-exchange monolithic column was successfully prepared.
• A strong anodic EOF was achieved over a wide pH range (4.0-9.0).
• Eight acidic compounds were rapidly separated with high column efficiency (up to 4.60 × 10^5 plates/m).
• Excellent run-to-run, day-to-day, and column-to-column reproducibility (RSDs < 5.0%) was demonstrated.

Conclusions:

• The developed N-benzylquininium-based anion-exchange monolithic column is highly effective for CEC.
• The column facilitates rapid and efficient separation of acidic compounds.
• The material exhibits good stability and reproducibility, making it suitable for practical applications.