Tailored graphene nanoparticles for biomedical application: preliminary in vitro characterization of the functionality in model cell lines.

Thanks to an environmentally friendly physical treatment of high purity graphite, a good control of the structure of graphene nanoparticles (GNPs) has been obtained with the production of stable and reproducible GNPs water dispersions. The preparation protocol entailed ball-milling of synthetic graphite followed by sonication in water and centrifugation/separation procedures. This way, two different GNPs samples with slightly different structural characteristics were harvested: TOP60, showing an average lateral size of the graphene layers  = 70 nm and average number of stacked layers  = 4, and BOTTOM60, with  = 120 nm and  = 6.