Effect of graphene oxide on bacteria and peripheral blood mononuclear cells

In this study we have tested the antibacterial activity and cytotoxicity towards peripheral blood mononuclear cells of three different graphene oxide samples, GO-H2O, GO-PBS and GO-MG. We have used AFM, SEM, Raman spectroscopy, XPS and TEM to characterize the morphology and composition of the materials. Our samples possess 2D sizes of ∼100nm (GO-H2O and GO-PBS) and >2μm (GO-MG). We confirm a size-dependent growth inhibition of Escherichia coli (DH5 α) in suspension and prove that this effect depends strongly on the protocol followed for exposure. No growth inhibition was observed when E. coli was put directly in contact with GO materials in LB broth, while the antibacterial effect was detected for GO-MG if exposure was carried out in saline solution during 1–3h. Hemocompatibility was confirmed by exposing peripheral blood mononuclear cells to the different materials for 24h, viability and apoptosis tests were carried out. Our experiments provide vital information for future applications of graphene oxide in suspension, if its antibacterial properties are to be potentiated, care should be taken to select 2D sizes in the micrometer range and exposure should not be carried out in presence of grow media.
Source: Toxicology Reports - Category: Toxicology Source Type: research