Preparation and characterization for a new sulfonic acid-functionalized mesoporous silica stationary phase

A novel strategy for functionalized mesoporous silica used as chromatographic packing material is reported. Periodic mesoporous silica containing sulfonic acid bearing groups were synthesized using tetramethyloxysilicate (TMOS) and mercaptopropyltrimethoxysilane (MPTMS) as framework precursors under acidic conditions in the presence of Pluronic P123 as surfactant and cetyltrimethylammonium bromide (CTAB) as cosurfactant. Conversion of the mercaptopropyl groups into sulfonic acid moieties was achieved via oxidation using hydrogen peroxide. Wormhole mesostructure with high surface area (up to 718.6 m2/g) and narrow pore size distribution (up to 4.0 nm) were obtained. The effect of the synthesized mesoporous silica microspheres as a HPLC packing material was examined.