Synthesis of core-shell silica spheres with tunable pore diameters for HPLC

Core-shell silica particles with fibrous shell structure and tunable pore size were prepared by using a dul-template method. The pore size of the core-shell silica particles was affected greatly by the amount of octadecylamine, which as used as cosurfactant. The pore size could be enlarged from 7.1 nm to 22.3 nm while keeping the unique fibrous shell structure. After derivatized with C18, the separation performances of these particles with a wider pore size were investigated. The column efficiency was as high as 219,789 plates m−1 for dimethylnaphthalene. Baseline separation of proteins ranging in size from 12 to 66 kD was achieved within 5 min. The separation results demonstrate that the synthesized core-shell silica particles would be a promising packing material in the rapid and high-resolution separation of both small solutes and macromolecules.