Cell culture flasks and dishes

The Cr₂O₃ particles were purchased from Nanostructured & Amorphous (Katy, TX, USA) Lot: 1910-091918 (particle A), and Sigma Aldrich (Steinheim, Germany) Lot: 634239 (particle B). Particle C (Lot: CHC 2018-19) was kindly provided by Lanxess (Cologne, Germany). CrCl₃ hexahydrate (≥97%) and K₂Cr₂O₇ (≥99.5%) were purchased from Carl Roth (Karlsruhe, Germany).
Dimethyl sulfoxide (≥99.9%) and 1,5-diphenylcarbazide (≥97.0%) were purchased from Sigma Aldrich (Steinheim, Germany). A CellTiter-Glo^® Luminescent Cell Viability Assay was purchased from Promega (Madison, WI, USA). All PCR consumables, including PCR tubes, strips, reaction tubes, and tubules, as well as cell culture dishes and flasks, were obtained from Sarstedt (Nuembrecht, Germany). The primer pairs were synthesized by Eurofins Genomics (Ebersberg, Germany) or Fluidigm (San Francisco, CA, USA). The DNA suspension buffer, PCR-certified water, and TE buffer were obtained from Teknova (Hollister, CA, USA). The 2X Assay Loading Reagent and 20X DNA Binding Dye Sample Loading Reagent were purchased from Fluidigm (San Francisco, CA, USA). Bio-Rad (Munich, Germany) provided the 2X SsoFastTM EvaGreen^® Supermix with Low ROX and the 2X SYBR Green Supermix. The 2X TaqMan^® PreAmp Master Mix was obtained from Applied Biosystems (Darmstadt, Germany) and exonuclease I from New England Biolabs (Frankfurt am Main, Germany).

All chemicals (p.a. grade), cell culture medium, and supplements were obtained either from Carl Roth GmbH (Karlsruhe, Germany) or Sigma-Aldrich Chemie GmbH (Taufkirchen, Germany) with the exception of fetal bovine serum (FBS), which was bought at Thermo Fisher Scientific GmbH (Dreieich, Germany). Cell culture dishes and flasks, reaction tubes, PCR tubes, and other consumables were purchased from Sarstedt (Nuembrecht, Germany). CuO NP were kindly provided by Dr. Wendel Wohlleben (BASF SE, Germany) in the course of the BMBF-funded project MetalSafety and originally synthesized and obtained from by PlasmaChem (Berlin, Germany). This particle species was also previously examined in the EU FP7-Project SUN, including oral and inhalation in vivo studies [28 (link),60 (link)]. Primer pairs were synthesized by Eurofins (Ebersberg, Germany). DNA suspension buffer, PCR certified water, and TE buffer were obtained from Teknova (Hollister, USA). The 2× Assay Loading Reagent, 20× DNA Binding Dye, and IFCs were purchased from Fluidigm (San Francisco, USA). The 2× SsoFast EvaGreen Supermix was provided by Bio-Rad (Munich, Germany), and the 2× TaqMan PreAmp Master Mix was bought from Applied Biosystems (Darmstadt, Germany). Exonuclease I was obtained from New England Biolabs (Frankfurt am Main, Germany).