Toxicity of silver nanoparticles in human macrophages: uptake, intracellular distribution and cellular responses

Silver nanoparticles (SNP) are among the most commercialised nanoparticles worldwide. They can be found in many diverse products, mostly because of their antibacterial properties. Despite its widespread use only little data on possible adverse health effects exist. It is difficult to compare biological data from different studies due to the great variety in sizes, coatings or shapes of the particles. In the present study, the authors applied a novel synthesis approach to obtain SNP, which are covalently stabilised by a small peptide. This enables a tight control of both size and shape. The authors applied these SNP in two different sizes of 20 or 40 nm (Ag20Pep and Ag40Pep) and analysed responses of THP-1-derived human macrophages. Similar gold nanoparticles with the same coating (Au20Pep) were used for comparison and found to be non-toxic. The cytotoxicity of particles was then assessed and their cellular uptake via transmission electron microscopy and confocal Raman microscopy was confirmed. Importantly a majority of the SNP could be detected as individual particles spread throughout the cells. Furthermore the authors studied several types of oxidative stress related responses such as induction of heme oxygenase I or formation of protein carbonyls. In summary, the present data demonstrate that even low doses of SNP exerted adverse effects in human macrophages.

Authors: Haase, A.; Tentschert, J.; Jungnickel, H.; Graf, P.; Mantion, A.; Draude, F.; Plendl, J.; Goetz, M. E.; Galla, S.; Masic, A.; Thuenemann, A. F.; Taubert, A.; Arlinghaus, H. F.; Luch, A. ;Full Authors: Journal of Physics: Conference Series 2011, 304, 012030/1-012030/14 (Eng) ;