title: Chemical mechanisms of the toxicological properties of nanomaterials: generation of intracellular reactive oxygen species.
abstract: As more and more nanomaterials with novel physicochemical properties or new functions are created and used in different research fields and industrial sectors, the scientific and public concerns about their toxic effects on human health and the environment are also growing quickly. In the past decade, the study of the toxicological properties of nanomaterials/nanoparticles has formed a new research field: nanotoxicology. However, most of the data published relate to toxicological phenomena and there is less understanding of the underlying mechanism for nanomaterial-induced toxicity. Nanomaterial-induced reactive oxygen species (ROS) play a key role in cellular and tissue toxicity. Herein, we classify the pathways for intracellular ROS production by nanomaterials into 1) the direct generation of ROS through nanomaterial-catalyzed free-radical reactions in cells, and 2) the indirect generation of ROS through disturbing the inherent biochemical equilibria in cells. We also discuss the chemical mechanisms associated with above pathways of intracellular ROS generation, from the viewpoint of the high reactivity of atoms on the nanosurface. We hope to aid in the understanding of the chemical origin of nanotoxicity to provide new insights for chemical and material scientists for the rational design and creation of safer and greener nanomaterials.
authors.affiliation: CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences and National Center for Nanosciences and Technology of China, Yuquan Rd 19 B, Beijing 100049 (P.R. China).
authors.forename: Liang
authors.initials: L
authors.lastname: Yan
authors.forename: Zhanjun
authors.initials: Z
authors.lastname: Gu
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D045222:Electron Transport Chain Complex Proteins / Q000378:metabolism; D051379:Mice; D008928:Mitochondria / Q000378:metabolism; D049329:Nanostructures / Q000737:chemistry* / Q000633:toxicity; D037742:Nanotubes, Carbon / Q000737:chemistry; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D045222:Electron Transport Chain Complex Proteins; D037742:Nanotubes, Carbon; D017382:Reactive Oxygen Species
keywords: nanoparticles; oxygen; reaction mechanisms; reactive intermediates; toxicity