A biocompatible medium for nanoparticle dispersion

Our laboratory has reported that rat bronchoalveolar lavage (BAL) fluid is an effective nanoparticle (NP) dispersant. However, its utility is constrained by its cost and the lack of standardization to control for intra- and inter-laboratory variability in BAL fluid. In this study, we report the efficacy and biocompatibility of a dispersion medium (DM), which is a 'lung fluid mimic'. In vitro studies, which used dynamic light scattering and transmission electron microscopy, determined that ultrafine titanium dioxide and ultrafine carbon black are equally well dispersed by DM or BAL fluid. We also determined that DM was effective at dispersing multi-walled carbon nanotubes. In vivo, when used as a vehicle, DM per se did not elicit toxicity and did not influence or alter toxic responses to crystalline silica in either the lung or brain. Overall, these studies indicate that DM is an effective, biocompatible, and economical vehicle for nanotoxicological studies.