Preparation and application of novel zwitterionic monolithic column for hydrophilic interaction chromatography

A novel zwitterionic hydrophilic porous monolithic stationary phase was prepared based on the thermal‐initiated copolymerization of N , N ‐dimethyl‐ N ‐(3‐methacryl‐amidopropyl)‐ N ‐(3‐(sulfopropyl)ammonium betaine and ethylene glycol dimethacrylate. A typical hydrophilic separation mechanism was observed at a highly organic mobile phase ( ACN >60%) on this optimized zwitterionic hydrophilic interaction chromatography ( HILIC ) monolithic stationary phase. Good permeability, stability, and column efficiency were observed on the final monolithic column. Additionally, a weak electrostatic interaction for charged analytes was confirmed in analysis of six benzoic acids by studying the influence of mobile phase p H and salt concentration on their retention behaviors on the obtained zwitterionic HILIC monolithic column. The optimized zwitterionic HILIC monolith exhibited good selectivity for a range of polar test analytes.