The main objective of WP5 is to characterise the “biological identities” of different nanomaterials after exposure in different biological media, i.e. blood plasma, serum, cell culture media, etc. These complexes will be characterised by diverse physiochemical approaches and proteomics in order to identify the identity of the biomolecules. It is expected that the main outcome of this study will be relevant for the correct understanding of nanoparticles related toxicity which will impact future safe implementation of nanomaterials.