An optimized dispersion of manufactured nanomaterials forin vitro cytotoxicity assays

Abstract

Colloidal characteristics of manufactured nanomaterials (e. g., hydrodynamic size distributions, surface charges, agglomeration, and sedimentation) in the actual toxicity test media have significant effects on the results ofin vitro toxicity assessments. Here, colloidal properties of widely used photocatalytic TiO2 (P25, Degussa Evonik GmbH) in commonly-usedin vitro cell culture media were carefully studied as a function of media types and their components (e. g., fetal bovine serum concentration). Temporal changes of optical densities at 340 nm and corresponding hydrodynamic size distributions were monitored for more than 48 hours by using UV-vis absorbance spectrometer and dynamic light scattering instruments. The colloidal stabilities of TiO2 dispersions were found strongly dependent on the added FBS concentrations as well as the type of the cell culture media used. Additionally, optimized dispersion and characterization protocol were proposed for easy and efficient way to monitor appropriate nanoparticle dosimetryin vitro.