Iron-based nanoparticles and their potential toxicity: Focus on oxidative stress and apoptosis

Recently, there have been several studies indicating that iron-based nanomaterials may exhibit certain toxic properties. Compared to conventional iron and iron oxides, iron nanoparticles (FeNPs) have some unique physical and chemical traits which impact their absorption, biodistribution and elimination. Facilitated passage through biological barriers enables FeNPs to reach various tissues and cells, and interact with a variety of different compounds. Currently, most of the recent research is focused on the potential cytotoxicity of FeNPs, and its implications on cell viability and functions. Some studies suggested that, in certain cell types, FeNPs may increase levels of oxidative stress and induce generation of reactive oxygen species. Oxidative stress may be one of the most important mechanisms by which FeNPs exhibit cytotoxic effects. Some authors have also suggested that, in certain conditions, exposure to FeNPs, in combination with other factors, may lead to changes in intracellular signaling resulting in programmed cell death. In this short review, we focus on the recent research on potential cytotoxicity of iron-based nanomaterials, and the potential implications of this new knowledge in medicine, chemistry and biology.