In a new study published in CHEM, researchers have shown that the immune system handles graphene oxide in a manner similar to pathogens, paving the way for safer biomedical applications of the two-dimensional material.

Graphene is the thinnest material known to man, a million times thinner than a human hair. Graphene oxide (GO), in turn, is an atomically thin material consisting only of carbon and oxygen atoms.

Graphene oxide (GO) is currently being considered for numerous uses including drug delivery and other medical applications. However, it is of critical importance to understand how these materials interact with the body.

In the study led by Professor Bengt Fadeel at the Institute of Environmental Medicine, Karolinska Institutet, it is shown that neutrophils, the most common type of white blood cell that is specialised in combating infections, release so-called neutrophil extracellular traps (NETs) when encountering graphene oxide (GO).

Neutrophil extracellular traps are made up of a spider-web of DNA decorated with proteins that help neutrophils to destroy microorganisms such as bacteria and fungi. The researchers found that graphene oxide causes specific changes in the lipid composition of the cell membrane of neutrophils leading to the release of NETs.

The research team could also show that antioxidant treatment reversed this process. In a companion study published in Nanoscale, it was shown that GO is degraded in NETs, much like bacteria and other pathogens.

Taken together, the studies show that GO can be trapped and degraded in NETs just like pathogens. Understanding how the immune system senses and handles GO paves the way for safer biomedical applications of GO and other graphene-based materials, for instance in the context of drug delivery.

The current study, performed at Karolinska Institutet in collaboration with Professor Kostas Kostarelos at the National Graphene Institute, University of Manchester, and the National Center of Imaging Mass Spectrometry at the Chalmers University of Technology.

The Graphene Flagship Project has over 150 academic and industrial partners and a total budget of €1 billion. The objectives are to develop new technologies and applications by exploiting the unique properties of graphene and other 2-D materials.