Liposomes as effective exfoliating agents for graphite

In the last years, graphene and its derivatives, have aroused interest in many research fields due to their unique physicochemical properties. For applications in biomedicine, one of the most important and fundamental goal to be achieved is to make graphene soluble in water. Up to now, most of the research on graphene in the biomedical field has been focused on the production and characterization of hydrophilic graphene oxide. Here we present the preparation of double and few-layer graphene aqueous dispersions by exploiting liposomes as effective exfoliating agents for graphite. Raman measurements evidenced the presence of non-oxidized double layer graphene and ordered phospholipid bilayers. TEM analyses confirmed the embedding of graphene nanosheets in the liposomal bilayer. The as-prepared graphene aqueous dispersions demonstrated to be stable for days highlighting significant antibacterial activity against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) strains.