Researchers at the National Institute of Standards and Technology (NIST) have, for the first time, demonstrated a method for producing nanoparticle clusters that will allow them to study the effects of nanoparticles on cells. Engineered nanoparticles have properties that make them attractive for myriad applications – they’re small as a virus, biologically and environmentally stable, and water soluble – but these same properties cause concern about their long-term impacts on environmental health and safety. The tendency for nanoparticles to clump together in solution is of particular interest, because the size of these clusters may be key to whether or not they are toxic to human cells. The NIST clusters can be made in a variety of controlled sizes that are stable over time. The NIST team took these clusters and mixed them with horse blood to study the impact of clumping size on red blood cell toxicity. The researchers found that red blood cell destruction decreased as cluster size increased, which led them to hypothesize that large nanoparticle clusters dissolve more slowly than small ones, thereby releasing fewer silver ions into solution. The team next plans to further characterize the different cluster sizes and use those clusters to study the impact on cytotoxicity of coatings applied to nanoparticles. The article can be viewed online at the link below.
http://www.nist.gov/mml/biochemical/nanoparticles-020111.cfm