Physicochemical and toxicological assessment of commercial 2D nanomaterials

Two-dimensional nanomaterials (2D) have attracted significant attention as next generation materials. Multiple applications due to physico-chemical proprieties and the fascinating layered structure of a thickness of at least one atomic layer have emerged. However, concerns have been raised about the safety and biocompatibility of 2D nanomaterials due to contradictory results in several in vitro and in vivo nanotoxicological studies. Specifically, scientific data on the potential hazard of nanoparticles has underline the capability of layered nanomaterials to cross biological barriers, inducing reduction on cellular viability and increasing oxidative stress. In the last decade, the application of 2D nanomaterials has seen a rapid growing in the industrial field and, as a consequence, the safety assessment is necessary in order to develop biocompatible and safe nanotechnology. Notwithstanding numerous research efforts being made in the past decade to assess the different toxicity of nanomaterials, most of these scientific works focus on laboratory made nanoparticles, without tackling numerous aspects, such as apposite nanoparticle physico-chemical characterization, relevant doses and exposure duration. Therefore, the aim of this PhD thesis is to investigate the possible in vitro acute toxic effects of several 2D nanomaterials beyond graphene, considering the different physico-chemical proprieties of commercial graphene oxide, transition metal dichalcogenides (TMDs) and boron nitride, as well as the potential chemical degradation and oxidation in the environmental fate of TMDs, taking into consideration the possible differences in the toxicological responses of different eukaryotic and prokaryotic cells. The main goal of this thesis was to use different cellular models and in vitro cytotoxic assays to address several challenges in nanotoxicology, in order to increase our understanding of the biological interactions between 2D nanomaterials and biological systems