Aluminum nanoparticles show promise as less toxic alternative to gold

Metallic nanoparticles are well-suited as drug carriers, biosensors, and diagnostic tools for biomedical applications. Gold nanoparticles, in particular, are simple to manufacture, functionalizable, and highly nonreactive, leading to their widespread adoption as safe materials.

However, the nonreactive nature of gold nanoparticles also makes them nearly impossible for the body to metabolize. Consequently, gold can build up in the body)s tissues and major organs. This can lead to detrimental effects, such as interrupting cell division and cell function.

Zhu et al. explored the extent to which gold nanoparticles can linger and accumulate in the body, and whether aluminum nanoparticles might be a safer alternative. They evaluated the cytotoxicity of both gold and aluminum nanoparticles in vitro as well as their accumulation and biotoxicity when intravenously injected into tumor-bearing mice.

“In our study, a significant accumulation of gold nanoparticles in the major organs was detected by inductively coupled plasma-mass spectrometry,” said author Tianmeng Sun. “We wanted to find other inorganic nanoparticles with both controlled morphology and easy metabolism and excretion in vivo.”

Compared with gold nanoparticles, the team observed less cytotoxicity from aluminum nanoparticles and no accumulation of these aluminum nanoparticles in the body except in the tumor tissue.

The results indicate that aluminum nanoparticles might be a safer alternative, and their specialized behavior in tumors could also have unique applications in cancer diagnosis or treatment.

“This unexpected phenomenon is very interesting,” said Sun. “However, the mechanism involved is still unclear. This will be the focus of our future research.”

Source: “Biosafety risk assessment of gold and aluminum nanoparticles in tumor-bearing mice,” by Ge Zhu, Zhihan Li, Yuning Zhang, Xiandi Meng, Meng Guan, Zheng Hu, Yong-Guang Yang, Kun Liu, and Tianmeng Sun, APL Bioengineering (2023). The article can be accessed at https://doi.org/10.1063/5.0144481 .

This paper is part of the Drug/Gene Delivery and Theranostics Collection, learn more here .