Cytotoxicity evaluation of magnetite (Fe3O4) nanoparticles in mouse embryonic stem cells.

Magnetite nanoparticles are expected to be applied in the medical field because of their biocompatibility and high saturated magnetization. In this paper, magnetite nanoparticles with a diameter of approximately 40 nm were evaluated for their safety by using mouse embryonic stem (mES) cells. First, various doses of magnetite nanoparticles were added to mES cells to find an optimal dose and to evaluate viability and keeping undifferentiated states of mES. The uptake of nanoparticles by mES cells was confirmed by using cytospin and transmission electron microscopy. Next, mES cells containing magnetite nanoparticles were collected by a magnet column 24h after the addition of magnetite nanoparticles, and the change in the ratio of those mES cells to the total mES cells was assayed by FACS 0, 4, 8, 12, 16, 24, 48 and 72 h after incubation. The result showed that the ratio decreased with time, indicating that the mES cells excreted the nanoparticles, for there was no change in the total number of cells. Based on these results, it was concluded that magnetite nanoparticles were safe to mES cells.