Characterization of engineered nanoparticles in simulated environmental and biological solutions

Although, numerous research papers prove high nanoparticles (NPs) toxicity, there is still lack of information about physicochemical behavior and fate of NPs in liquid biological and environmental media. This does not so far allow predicting the behavior of engineered NPs and establish regular correlations between concentration/dose of engineered NPs and their cytotoxic effects / response. NPs radically change their properties when entering the environment NPs due to surrounding composition and properties. That is why, the analysis of nanomaterials in different matrixes should not be limited to the determination of the composition and concentration since their environmental fate is affected by particle number, charge, size and size distribution, surface area, structure and shape, state of aggregation and elemental composition. Nevertheless, the information about physicochemical behavior and fate of nanoparticles in liquid biological and environmental media (saliva, sweat, lung fluid, etc.) is still limited. This does not so far allow predicting the behavior of nanoparticles and establish regular correlations between the physicochemical state of engineered nanoparticles and cytotoxic effects. Current presentation will include experimental data obtained on differently concentrated engineered Ni nanopowder produced by Advanced Powder Tech. Co (Russia). With the help of different approaches (dilution, centrifugation, filtration, sonication, etc.) we used ten-fold dilution to prepare differently concentrated suspensions of Ni NPs. Meaning that particles size analysis of differently loaded suspensions cannot be done with the same technique. We used single particle inductively coupled plasma mass spectrometry (particle loading 0.02 mg / L), photon cross-correlation spectroscopy (0.2 mg / L), nanoparticle tracking analysis (2 mg / L), dynamic light scattering (20 mg / L) and laser diffraction method (200 mg/L) to quantify NPs suspensions. (author)