Preparation of superficially porous core-shell silica particle with controllable mesopore by a dual-templating approach for fast HPLC of small molecules

Abstract

A novel strategy to synthesize the monodisperse superficially porous core-shell silica microspheres (CSSMs) with enlarged mesopore channels perpendicular to the particles surface using a dual-templating approach was presented for the first time. With hexadecyl trimethyl ammonium bromide (CTAB) as the template and trioctylmethylammonium bromide (TOMAB) as an auxiliary chemical to enlarge the size of CTAB micelles, the pore size can be enlarged from 2.6nm to 10.6nm, the mesopore channels perpendicular to the surface of CSSMs can be obtained. The particles synthesized in this work have a uniform mesoporous shell of about 198.3nm in thickness over the silica core and possess a surface area of ca. 85.1m2/g, and narrow pore size distribution. This preparation method is highly versatile, controllable and easy to operate. The CSSMs obtained were modified with octadecyltrichlorosilane (ODS) to separate the alkyl benzene homologues. The higher efficient separation with fast flow rate and relatively low back pressure of the synthesized column demonstrate that the CSSMs have a great potential application for fast separation and analysis of small solutes with high performance liquid chromatography (HPLC).