Evaluation of iron oxide nanoparticle biocompatibility

Abstract

Nanotechnology is an exciting field of investigation for the development of new treatments for many human diseases. However, it is necessary to assess the biocompatibility of nanoparticles in vitro and in vivo before considering clinical applications. Our characterization of polyol-produced maghemite γ-Fe₂O₃ nanoparticles showed high structural quality. The particles showed a homogeneous spherical size around 10 nm and could form aggregates depending on the dispersion conditions. Such nanoparticles were efficiently taken up in vitro by human endothelial cells, which represent the first biological barrier to nanoparticles in vivo. However, γ-Fe₂O₃ can cause cell death within 24 hours of exposure, most likely through oxidative stress. Further in vivo exploration suggests that although γ-Fe₂O₃ nanoparticles are rapidly cleared through the urine, they can lead to toxicity in the liver, kidneys and lungs, while the brain and heart remain unaffected. In conclusion, γ-Fe₂O₃ could exhibit harmful properties and therefore surface coating, cellular targeting, and local exposure should be considered before developing clinical applications.

Keywords:

• nanoparticles
• polyol process
• endothelial cell
• cytotoxicity
• clearance

Acknowledgements

The authors are indebted to Dr F Herbst and Dr M Hamadi for their assistance in electron microscopy analysis and chemical NP surface modification. This research was supported by a grant from Ligue Nationale contre le Cancer, comite de Paris, the CMCU France-Tunisia Cooperation Research Program and Association pour la Recherche sur le Cancer. AH is supported by a PhD fellowship from the Ministere des Affaires Etrangeres, Bourse d’Excellence Eiffel.

Disclosure

The authors report no conflicts of interest in this work.