Preparation and application of Au nanoparticles-decorated SO3H-cofunctionalized silica stationary phase for per aqueous liquid chromatography

Au nanoparticles (Au NPs)-decorated SO 3 H-cofunctionalized porous silica particles was prepared as a novel mixed-mode stationary phase and used in Per aqueous liquid chromatography (PALC) mode. The obtained stationary phase was characterized by elemental analysis, FT-IR spectra, and transmission electron microscopy. To evaluate the retention behavior, the effect of a variety of chromatographic factors on the retention of different types of solutes was investigated. The obtained column exhibited a hydrophobic interaction/cation-exchange mixed-mode retention mechanism, and a typical PALC characteristic was observed in water-rich mobile phases. When the particle size of Au NPs was 10–20 nm, the analytes had a sharp peak shape and the column pressure was also moderate. Compared with the hydrophilic interaction liquid chromatography (HILIC) and C 18 column, some hydrophilic compounds such as six monosaccharides were baseline separated with the enhanced resolution of the obtained column under the PALC mode. Moreover, the efficiency of the Au-S/SO 3 H-SiO 2 -2 column was significantly higher than that of the HILIC column. PALC mode was a green annlysis method and suitable for the replacement of hydrophilic interaction liquid chromatography.