Finally in the sky! Graphene eventually degrades into CO2 in the body?

Graphene is a two-dimensional nanomaterial with a wide range of applications in many fields of science and technology, including advanced biomedical applications. Graphene has a larger specific surface area, for example, can produce excellent drug adsorption tendency, and photoluminescence properties of inherent, although can promote living cells have potential use in biomedical applications, but graphene research is limited to preclinical research, part of the reason is to understand the fate of the graphite in the body is limited, especially in the long term.

Therefore, the distribution and clearance of graphene materials as drug delivery systems at the organ and suborgan levels remains unclear for a long time. In particular, what is the final product of graphene in the body? No one has studied it systematically yet.

Results summary







To this end, Liang MAO of Nanjing University, Tian Xia of the University of California, USA, and others compared the fate of 14C-labeled oligo graphene with different side sizes after one year of intravenous injection in mice. The results showed that the oligo graphene mainly accumulates in the liver, and the larger graphene can be degraded to 14CO2 by Kupffer cells.

What is the mechanism?



Mechanisms include liver cell uptake of graphene, larger graphene-induced erythrocyte membrane perturbation, and enhanced erythrocytic phagocytosis by Kupffer cells, leading to the degradation of hemoglobin to heme and increased cell iron concentration. The increase of iron triggered the Fenton reaction, which produced hydroxyl radicals and promoted the degradation of larger graphene to 14CO2.

Kun Lu, et al. Kupffer Cells Degrade 14C-Labeled Few-Layer Graphene to 14CO2 in Liver through Erythrophagocytosis. ACS Nano, 2020.



DOI: 10.1021 / acsnano. 0 c07452



https://doi.org/10.1021/acsnano.0c07452