The toxicity of gold nanoparticles (AuNPs) varies significantly with size according to studies at the Joint Research Centre (JRC) in Ispra, Italy.
In tests on mouse cells in vitro, gold nanoparticles damaged the cellular scaffolding known as the cytoskeleton, with smaller (5nm) particles causing more harm than larger (15nm) ones. “It would be interesting to identify, from the mechanistic point of view, how AuNPs of different sizes affect cells biology,” write the JRC scientists.
The study showed the total gold content in the cells to increase steadily with exposure time, while nanoparticles did not reach the cell nucleus, but were confined in vesicles within the cell.
In particular, the study found that cytotoxicity results are easier to interpret when combined with cell interaction studies using transmission electron microscopy (TEM) and inductively-coupled mass spectrometry (ICP–MS).
The research is published in Toxicology Letters.