Synthesis and Characterization of Biocompatible and Size-Tunable Multifunctional Porous Silica Nanoparticles

In this work, size-controlled multifunctional mesoporous silica nanoparticles having large surface areas, embedded luminescence, high magnetization, and excellent aqueous dispersity have been successfully prepared by using a simple one-pot synthesis. The size and pore ordering of these particles can be easily controlled based on the number density of Fe3O4 nanoparticle nucleation sites introduced during the silica condensation reaction. Dissolution of the embedded Fe3O4 nanoparticles yields hollow mesoporous silica nanoparticles as well. These multifunctional porous nanoparticles were characterized by transmission electron microscopy, X-ray diffraction, nitrogen adsorption-desorption behavior, dynamic light scattering, zeta potential, magnetic susceptibility, and photoluminescence. Furthermore, in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) and hemolysis assays were performed to evaluate any unintended cytotoxicity. The biocompatibility of the multifunctional nanoparticles, even at very high doses, ensures their potential in biomedical applications.