Dialysis process for the removal of surfactants to form colloidal mesoporous silica nanoparticles

Colloidal mesoporous silica nanoparticles less than 20 nm in diameter are prepared by dialysis; this simple surfactant removal route can avoid aggregation by sedimentation–redispersion and remove cationic surfactants while retaining the original colloidal state, which is applicable to the preparation of primary nanoparticles carrying a functional organic substance.