Test materials, like manufactured nanomaterials (MN), may interact with serum proteins, interleukins (IL) and lactate dehydrogenase (LDH) and cause measurement artefacts as a result of e.g., physical adsorption and electrostatic forces, and/or interaction with dissolved species or conditional chemical changes during testing. In this article, data are given on the zeta-potentials of two manufactured ZnO nanomaterials (NM-110 and NM-111) dispersed in 0.05% w/v Bovine Serum Albumin (BSA) water batch dispersions and in Ham's F12 nutrient mixture added Fetal Bovine Serum (FBS), penicillin, and streptomycin and particle free mediums (cHam's F12). Data on the Zeta-potential and the iso-electrical point of lactate hydrogenase in pure Ham's F12 nutrient mixture is also provided. The percentage of added IL-6, IL-8 and LDH remaining after 24-h incubation in cHam's F12 are given as function of MN concentrations. Finally data from thermodynamic chemical reaction modeling of changes in pH and Zn-speciation during dissolution of ZnO or dissolved ZnCl2 additions to Ham's F12 using Geochemist Workbench® are given. For further information, data interpretation and discussion please refer to the research article “Interaction of biologically relevant proteins with ZnO nanomaterials: a confounding factor for in vitro toxicity endpoints” (E. Da Silva et al. 2019).