title: Copper ions interfere with the reduction of the water-soluble tetrazolium salt-8.
abstract: Metabolic activity as a measure of cell viability is frequently determined using the water-soluble tetrazolium salt 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium monosodium salt (WST-8), commercially available as CCK-8 reagent. In this study, CCK-8 was investigated with respect to its suitability for investigating nano- and microscale copper oxide (CuO NP and CuO MP) as well as water-soluble copper chloride (CuCl2). The results were compared to cell number and colony forming ability. Our data demonstrate that the CCK-8 assay overestimates the loss of metabolic activity by CuCl2 and CuO NP, because of interference by copper ions with the reduction of the dye.
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institute of Applied Biosciences, Department of Food Chemistry and Toxicology, Adenauerring 20a, 76131 Karlsruhe, Germany.
authors.forename: Annetta
authors.initials: A
authors.lastname: Semisch
authors.forename: Andrea
authors.initials: A
authors.lastname: Hartwig
mesh_terms: D016477:Artifacts; D002452:Cell Count; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003300:Copper / Q000633:toxicity*; D006801:Humans; D053758:Nanoparticles / Q000633:toxicity*; D010084:Oxidation-Reduction; D012995:Solubility; D013778:Tetrazolium Salts / Q000737:chemistry / Q000378:metabolism*; D014867:Water / Q000737:chemistry
chemical_list: C476329:2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H tetrazolium monosodium salt; D013778:Tetrazolium Salts; D014867:Water; D003300:Copper; C029892:cupric chloride; C000520:cuprous oxide