Phosphate-enhanced cytotoxicity of zinc oxide nanoparticles and agglomerates.

Highlights: [•] NIH/3T3 cells were exposed to individualized and agglomerated ZnO nanoparticles. [•] The cytotoxic response in growth media with and without phosphates was assessed. [•] With phosphates present, zinc phosphate formation enhanced cell death. [•] Agglomeration-dependent cell death only existed in the presence of phosphates. [•] Nanomaterial interactions with growth media constituents can be easily overlooked. [Copyright &y& Elsevier]