RESUMO
This paper gives information on the action of nanoparticles when interacting with biological objects and penetrating into them. The high chemical activity of nanoparticles determines their enhanced biological activity against living organisms. Due to their special properties and sizes, the nanoparticles can penetrate across the cell membranes or between the cells and spread to various organs and systems by different mechanisms (endocytosis and transcytosis). In vitro and in vitro investigations of human exposure to nanopowders strongly suggest the occurrence of inflammatory processes, oxidative stresses in the lung and peripheral organs when such powders are inhaled. A few days after intracheal administration, the nanoparticles (30-60 nm in size) penetrate into the cells of the liver, kidney, and gonads and, moreover, primarily impair the mitochondria and penetrate into the nucleus, carrying the viruses on their arms into the cell nucleus. By taking into account the penetrating capacity of nanoparticles into various human organs and tissues and into cell substances, there are a number of problems and questions as both positive in the use of nanoparticles in medicine and other branches of industry as materials that can deliver a drug to the involved organs, by improving the properties of many materials, and negative, such as the development of new forms of abnormalities that are still unknown medicine. In this connection, it is necessary to develop technical regulations on their manufacture, use, storage, transportation, and utilization and those on the realization of various imported materials containing the nanoparticles and obtained by nanotechnologies.
