(82f) Sol–Gel Synthesis of Phosphorylcholine-Type Zwitterion-Decorated Silica Gels

Zwitterion-functionalized silica particles are desirable as antifouling, highly hydrated, biocompatible materials. However, existing methods to covalently attach zwitterionic groups to the silica particle surface generally require significant synthesis and purification procedures. This work describes a simple, one-pot, acid-catalyzed sol–gel synthesis approach utilizing L-α-glycerophosphorylcholine (GPC) to create phosphorylcholine (PC)-type zwitterionic silica gels via the condensation of hydroxyl groups on GPC with silanol groups generated during the reaction. This approach was successfully employed to create both PC-modified xerogels and ionogels (ionic liquid electrolyte-rich, silica-supported gels). Silica gel particle morphologies and surfaces were characterized using scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS). SEM imaging revealed significant differences in primary silica particle size and roughness for samples prepared with GPC compared to control samples. EDS data indicated the presence of approximately 2–3 wt. % phosphorus (from GPC) on silica surfaces after thorough washing. This study highlights the promise of a simple, one-pot method for producing PC-decorated silica gels and presents future design possibilities for other novel materials leveraging zwitterionic molecules.