A polymer-based zwitterionic stationary phase for hydrophilic interaction chromatography

Area of Science:

• Chromatography
• Materials Science
• Analytical Chemistry

Background:

• Hydrophilic interaction chromatography (HILIC) is crucial for separating polar compounds.
• Development of novel stationary phases is essential for advancing HILIC performance.
• Existing HILIC phases often face limitations in stability or selectivity.

Purpose of the Study:

• To synthesize and characterize a novel polymer-based zwitterionic stationary phase for HILIC.
• To evaluate the hydrophilicity, stability, and separation capabilities of the new phase.
• To assess the phase's performance in separating polar and ionic analytes, including simultaneous anion and cation separation.

Main Methods:

• Chemical modification of poly (glycidyl methacrylate-divinylbenzene) (GMA-DVB) microspheres.
• Surface functionalization via hydrolysis to create diol groups and "thiol-ene" click chemistry to attach cysteine.
• Characterization using scanning electron microscopy, elemental analysis, and zeta potential measurements.
• HILIC separation of polar and ionic analytes, evaluating stability at alkaline pH and bleed levels.

Main Results:

• Successful synthesis of a polymer-based zwitterionic stationary phase with diol and zwitterionic groups.
• The phase exhibited good hydrophilicity, enabling effective separation of common polar analytes.
• Demonstrated excellent stability in alkaline solutions (pH 10) and negligible bleed compared to commercial phases.
• Achieved specific separation selectivity for ionic analytes, including simultaneous separation of anions and cations.

Conclusions:

• The novel polymer-based zwitterionic stationary phase offers a promising alternative for HILIC applications.
• Its robust hydrophilicity, stability, and low bleed characteristics make it suitable for analyzing polar and ionic compounds.
• The phase's unique selectivity provides a valuable tool for complex mixture analysis in chromatography.