Abstract

Nanomaterials’ use and applications have increased during the last decade in the biomedical field, particularly metallic nanoparticles (MNPs), because of their unique physical and chemical properties. However, how those properties are affected by biological environments is known to a lesser extent. Recently, several reports have proven that the interaction of nanomaterials with biological’s free radicals can promote toxicities to human health due to changes in their structural and physicochemical properties. Moreover, activation of the immune system´s cells, such as the phagocytic ones, e.g., macrophages, is prone to over-induce an immune response because of nanomaterial’s presence, promoting long-term diseases related to oxidative stress. This chapter will discuss the use of nanomaterials, focusing on metal nanoparticles and their role in promoting oxidative stress at the biological level and its consequences. Further, inputs related to overcoming the current limitations of nanomaterials in biological environments are given.