Nanoparticles. In nanotechnology, a particle is defined as a small object that behaves as a whole unit with respect to its transport and properties. Particles are further classified according to diameter.[1] Coarse particles cover a range between 2,500 and 10,000 nanometers. Fine particles are sized between 100 and 2,500 nanometers. Ultrafine particles, or nanoparticles, are between 1 and 100 nanometers in size.
The reason for this double name of the same object is that, during the 1970-80s, when the first thorough fundamental studies with "nanoparticles" were underway in the USA (by Granqvist and Buhrman)[2] and Japan, (within an ERATO Project)[3] they were called "ultrafine particles" (UFP). However, during the 1990s before the National Nanotechnology Initiative was launched in the USA, the new name, "nanoparticle," had become fashionable (see, for example the same senior author's paper 20 years later addressing the same issue, lognormal distribution of sizes [4]).
IUPAC definition Background[edit] 81108 Micro particles based on silicium dioxide size: 2 μm. 310050 Iron(III) oxide powder, <5 μm, ≥99% 483036 Fullerene-C60 98% 240664 1,2-Dichlorobenzene anhydrous, 99% 637246 Silicon dioxide nanopowder (spherical, porous), 5-15 nm particle size (TEM), 99.5% trace metals basis. 637238 Silicon dioxide nanopowder, 10-20 nm particle size (SAXS), 99.5% trace metals basis. Nanotoxicology. Nanotoxicology is the study of the toxicity of nanomaterials. Because of quantum size effects and large surface area to volume ratio, nanomaterials have unique properties compared with their larger counterparts.
Nanotoxicology is a branch of bionanoscience which deals with the study and application of toxicity of nanomaterials.[1] Nanomaterials, even when made of inert elements like gold, become highly active at nanometer dimensions. Nanotoxicological studies are intended to determine whether and to what extent these properties may pose a threat to the environment and to human beings.[2] For instance, Diesel nanoparticles have been found to damage the cardiovascular system in a mouse model.[3] Human health and safety[edit] Carbon nanotubes – characterized by their microscopic size and incredible tensile strength – are frequently likened to asbestos, due to their needle-like fiber shape. California[edit] Toxicology of nanoparticles[edit] Background[edit] Reactive oxygen species[edit]