. 2022 May 25;12(11):1810. doi: 10.3390/nano12111810

Table 1.

Main interferences from nanomaterials in some of the most widely used conventional toxicological assays identified so far.

Conventional Methodology	Observed Interference		Proposed Solution
Conventional Methodology	Cause	Result/Interpretation	Proposed Solution
MTT reduction LDH leakage WST reduction	NM optical density; NM aggregation in cell medium	Falsely increased viability	Sample centrifugation after cell lysis
MTT reduction LDH leakage WST reduction	NM redox activity	Falsely decreased viability	None
ELISA (cytokine release)	Protein adsorption to NMs	Falsely decreased cytokine production	Add serum proteins to NM suspension
Comet assay	Interference enzyme activity	Falsely decreased genotoxicity	None
ROS quantification (H₂DCF-DA)	NM redox activity	Falsely increased ROS levels	None
ROS quantification (H₂DCF-DA)	NMs quench fluorescence; NMs scatter emitted fluorescence	Falsely decreased ROS levels	Sample centrifugation after cell lysis

NM: nanomaterial; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; LDH: lactate dehydrogenase; WST: water-soluble tetrazolium salts; ELISA: enzyme-linked immunosorbent assay; ROS: reactive oxygen species; H₂DCF-DA: 2′,7′-dichlorodihydrofluorescein diacetate.