Polymethacrylate-based monolithic column with incorporated carbamide-modified fumed silica nanoparticles for hydrophilic liquid interaction chromatography

Abstract

In this proof-of-concept study, new monolithic columns were prepared by incorporating fumed silica nanoparticles (FNSPs) that are surface functionalized by covalent attachment of 1-[3-(trimethoxysilyl)propyl]urea moieties (i.e., carbamide-FSNPs). The prepared monolithic columns were successfully utilized in hydrophilic interaction liquid chromatography (HILIC) of small, relatively polar solutes. The organic polymer monolithic matrix was based on the in situ polymerization of glyceryl monomethacrylate (GMM) and ethylene glycol dimethacrylate (EDMA) yielding the poly(GMM-co-EDMA) monolith for the incorporation of carbamide-FSNPs. The poly(GMM-co-EDMA) monolithic column with incorporated carbamide-FSNPs which is referred to as carbamide-FSNPs-poly(GMM-co-EDMA) was investigated over a wide range of mobile phase compositions with polar acidic, weakly basic and neutral analytes including organic acids, food additives, vitamins, biological amines, nucleosides, nucleobases, dimethylformamide, formamide and thiourea. Improved peak shapes and better separations were achieved when anisocratic (i.e., gradient) elution conditions were used for the separation of nucleobases, nucleosides and vitamins. The run-to-run, day-to-day and column-to-column reproducibilities were satisfactory.

Graphical Abstract

Keywords:

• Fumed silica nanoparticles
• high performance liquid chromatography
• hydrophilic interaction liquid chromatography
• polymethacrylate based monolith
• ureidopropyltrimethoxysilane