Physical-chemical characterization of tungsten carbide nanoparticles as a basis for toxicological investigations

Abstract

One task in risk assessment of engineered nanoparticles is toxicological studies. A suitable interpretation of these investigations demands a comprehensive physical-chemical characterization. Here, we present an approach to gain well-dispersed nanoparticles in physiological media. Therefore, a step-by-step procedure is demonstrated on two different tungsten carbide nanopowders which can be transferred to other powders. The procedure includes a comprehensive powder characterization, followed by a preparation of a non-physiologic, electrostatically stable nanoparticle suspension and finally closes with investigations of the particles' behavior in different physiological media. Our study showed that the particles agglomerate in protein-free media. In this context, dependencies of mass- and surface-based nanoparticle concentrations as well as of different physiological media were analyzed. In the presence of bovine serum albumin (BSA) or serum, the agglomeration process is decelerated or, at the appropriate protein amount, prevented.

Keywords::

• Particle characterization
• nanoparticles
• suspension preparation
• tungsten carbide
• toxicity

Declaration of interest: This work was partially funded by the German Federal Ministry of Education and Research (BMBF) for the INOS project (grant 03X0013). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.