Oxidized silicon nanoparticles for radiosensitization of cancer and tissue cells.

KLEIN, S; DELLARCIPRETE MARÍA LAURA; M. WEGMANN; L. V DISTEL, W.; W. NEUHUBER; M. C GONZALEZ; C. KRYSCHI

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2013 vol. 434 p. 217 - 222

0006-291X

The applicability of ultrasmall uncapped and amino-silanized oxidized silicon nanoparticles (i.e. SiNPs and NH2-SiNPs) as radiosensitizer was studied by internalizing these nanoparticles into human breast cancer (MCF-7) and mouse fibroblast cells (3T3) that were exposed to X-rays at single doses of 3 Gy. While the SiNPs were not observed to increase the production of reactive oxygen species (ROS) in the X-ray irradiated cells, the NH2-SiNPs exhibit a large enhancement effect on the ROS formation. This is due the amino functionality that attains a positive surface charge in aqueous environment. Therefore the NH2-SiNPs may penetrate into the mitochondrial membrane, wherein these nanoparticles may provoke oxidative stress which will be enhanced under X-ray treatment. However, cytotoxicity studies demonstrate that NH2-SiNPs are less biocompatible for MCF-7 than for 3T3 cells. Moreover, X-ray exposure of cells containing NH2-SiNPs were observed to increase the ROS concentration in MCF-7 cells for 180 % and in 3T3 cells for 123 %. This is confirmed by the determination of the lipid peroxidation (LPO) level in MCF-7 cells that was observed to rise for about 210 %.