Gold Nanoparticle Toxicity in Mice and Rats: Species Differences

Area of Science:

• Nanomedicine
• Toxicology
• Biomedical Engineering

Background:

• Advancing nanomedical technologies requires comprehensive nanotoxicity assessments.
• Gold nanoparticles (GNPs) are widely used in biomedical applications, necessitating safety evaluations.

Purpose of the Study:

• To evaluate the toxic effects and biodistribution of gold nanoparticles (GNPs) following intravenous administration in mice and rats.
• To identify potential species-specific differences in GNP toxicity and biological responses.

Main Methods:

• Commercially available 15-nm GNPs were characterized and administered intravenously to mice and rats at a dose of 1,000 mg/kg.
• Animals were monitored, and biological samples were collected at multiple time points (1-28 days) post-exposure for toxicological and biodistribution analyses.

Main Results:

• Mice exposed to GNPs developed liver granulomas and transient increases in interleukin-18, a pro-inflammatory cytokine.
• Rats exhibited mortality within hours of GNP administration, with distinct biodistribution patterns including higher spleen accumulation and greater fecal excretion compared to mice.
• No mortality was observed in mice, but significant species-specific differences in toxicity, biodistribution, and excretion were evident.

Conclusions:

• Gold nanoparticles (GNPs) can elicit a significant macrophage response in mice.
• Significant species-specific variations exist in the biodistribution, excretion, and toxicity of GNPs, highlighting the need for careful consideration in nanomedical applications.