Temperature-responsive ionic liquid hydrogel coating silica used for multi-mode chromatographic stationary phase

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• High-performance liquid chromatography (HPLC) stationary phase development focuses on efficient synthesis and precise regulation.
• Achieving multi-mode chromatographic separation requires stationary phases with multiple interaction types (hydrophobic, hydrophilic, ion-exchange).

Purpose of the Study:

• To synthesize a novel stationary phase with multi-modal separation capabilities.
• To investigate the interaction mechanisms and temperature-responsive characteristics of the new stationary phase.

Main Methods:

• Modification of bare silica surface with an ionic liquid hydrogel to create the Sil@V1NV2 stationary phase.
• Evaluation of the stationary phase's performance in hydrophilic interaction liquid chromatography (HILIC), reversed-phase liquid chromatography (RPLC), and ion-exchange chromatography (IEC).

Main Results:

• The synthesized Sil@V1NV2 stationary phase exhibited amplified hydrophobic and introduced ion-exchange interactions compared to hydrophilic hydrogels.
• Sil@V1NV2 demonstrated capability for multi-mode separations, including HILIC, RPLC, and IEC.
• The retention factor (k) for certain analytes did not follow the Van't Hoff equation, and the stationary phase showed temperature-responsive characteristics.

Conclusions:

• The novel Sil@V1NV2 stationary phase enables multi-modal chromatographic separations by combining diverse interaction mechanisms.
• The temperature-responsive behavior of the ionic liquid hydrogel broadens the application scope of chromatographic separations.
• This research provides a reference for developing advanced ionic liquid hydrogel-based stationary phases.