STUDY OF THE INTERACION BETWEEN CELLS AND SILICA NANOPARTICLES WITH DIFERENT SIZE AND SURFACE

P. EVELSON; A. M. MEBERT; D. MAYSINGER; M. F. DESIMONE

Congreso; XX Jornadas Anuales de la Sociedad Argentina de Biología y XVII Jornadas de la Sociedad Uruguaya de Biociencias; 2018

Silica nanoparticles (SiNPs) are currently being used in cosmetic products, food, paints, and other industries and is widely believed to be an important material for biomedical and drug delivery applications. They can be produced using synthetic techniques with precise size control and physical and chemical properties. Human exposure to nanosilica can occur unintentionally in daily life and in industrial settings. With the aim of studying its interaction with human body different size (60 nm, 100nm and 300 nm) SiNPs were synthesized by Stöber method and surfaced grafted (bare -OH, amino -NH2 and thiol -SH) with organosilane chemistry using (3-aminopropyl)triethoxysilane (APTES) and (3-mercaptopropyl)trimethoxysilane (MPTMS). In the present work, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay were performed to evaluate the cytotoxicity of these NPs in cervix (HeLA), lung (A549) and brain (U251) cell line cultures. To determine nanoparticles fate after cell exposure, fluorescent rhodamine labeled 60 nm silica particles were synthesized and grafted with APTES or MPTMS to obtain amino modified and thiol modified fluorescent labeled particles. Size, dispersity and surface were studied by scattering electronic microscopy (SEM) as well as the hydrodynamic diameter by dynamic light scattering (DLS) and surface grafting by fourier-transform infrared spectroscopy (FT-IR). Results show that no evident cytotoxicity in the tested concentration and time, up to 30 ppm and 72 h. Internalization studies shown that those NPs grafted with positively charged groups were more capable to enter the cells.