Preparation and evaluation of a hydrolytically stable amide-embedded stationary phase.

We have developed a new hydrolytically stable amide-embedded stationary phase via a simple and effective synthetic method. The preparation of the new phase involves the synthesis of multifunctional silane ligands and the surface modification of porous silica particles via multiple attachments of these ligands to the silica surface. A hydrolytically stable coating was produced as a result of multiple covalent linkages formed between silane ligands and the silica surface, and cross-linking between adjacent ligands. The resulting amide-embedded stationary phase showed excellent hydrolytic stability over a wide pH range. Like other existing amide-embedded columns, this new stationary phase exhibits higher retention for polar compounds and different selectivity as compared to conventional C18 columns. The new phase is compatible with 100% aqueous mobile phases, and also provides high column efficiency and good peak shapes for both acidic and basic compounds.