Nanomaterials: Cytotoxic or Biocompatible?

Background and Aims: Nanomaterials exhibit outstanding chemical and physical properties compared to solid materials. Their application potential in many procedures involving surface coating, semiconductor manufacture and medical technology appears profitable. Nevertheless, nanoparticles may represent an uncal-culable health risk, due to possible adsorption pathways (skin, mucous membranes and lung) in the body. In blood, they can agglomerate with lipophilic proteins and reach many cell types and tissues. Through their high surface and residual concentration in catalyst materials these bioactive particles can harm cells by bringing about inflammation reactions, oxidative stress and even necrosis and apoptosis. Methods: For testing the biocompatibility according to DIN ISO 10993-5, we examined carbon nanotubes (CNT) for possible cy-totoxic characteristics. Compared with special reference materials, proliferation attitude as well as inflammation mediators were measured with relevant primary cells and cell lines after incubation with CNTs. In addition, established 3D test systems, such as skin and trachea with human primary cells, facilitate the obtaining of new information about how CNTs can bridge body barriers. Results: Our findings showed a changed proliferation attitude to CNT incubation relating to CNT kind, size distribution and residual concentrations of catalyst material. Further biocompatibility tests for other nanomaterials need to be established. Conclusions: Through exact material characterisation as well as examination of biocompatibility by means of in vitro tests, health risks can be estimated.