Flow-through silica: A potential matrix for fast chromatographic enantioseparation with high enantioselectivity

Abstract The demand for fast chromatographic enantioseparation aroused the hot research in stationary phase matrix. In the present study, the flow-through silica, which is characterized by hierarchical pores of through pores in several hundred nanometer range and mesopores about 20 nm, was attempted for fast enantioseparation. Thanks to the large surface area and full openness of the through pores, the flow-through silica had comparable cellulose derivative loading amount as the commercial wide-pore silica, which was impracticable for most of the core-shell particles and sub-2-μm fully porous silica. In addition, the backpressure was about two times lower in the case of the flow-through silica of the same particle size to the commercial wide-pore silica, due to the highly porous structure of the former. Another appreciated merit of the flow-through silica in small size (~2 µm) was the less dependence of column efficiency on the flow rate. All of the above features rendered the flow-through silica a tremendous potential for fast enantioseparation with desired enantioselectivity, especially suitable for the polysaccharide chiral selector.