Hybrid nanosilicas produced by the Stöber sol-gel process: In vitro evaluation in MRC-5 cells

Abstract

A series of 12 organosilanes exhibiting different steric and electronic properties were employed in the synthesis of hybrid silicas by the Stöber sol-gel process. The resulting materials were characterized by a set of complementary techniques (nitrogen adsorption, dynamic light scattering, small-angle X-ray scattering, transmission electron microscopy, and carbon content analysis).. Hybrid silicas bearing polyethylene glycol (PEG), zwitterion (ZWT), and methyl (C1) moieties improved the physical-chemical properties of the nanoparticles for biological applications. Toxicological safety tests were performed on the fibroblast cell line (MRC-5), which showed that the functionalization of silica nanoparticles with PEG and ZWT increased cell viability, 111 ± 8.5% and 114 ± 6.3%, respectively, when compared to that of nanomaterials without functionalization, 98 ± 8.8%. Both functionalized and non-functionalized silica nanoparticles did not cause any damage to the DNA of the cells, even at the highest doses.