Measurement of Redox Potential in Nanoecotoxicological Investigations

Table 2

Mean values of zetapotential (of six replicates) for different nanomaterials dispersed in various media. DI water + 5 mM NaCl—this medium was employed to compare with the DI results when in the presence of inert background electrolyte. Values are the mean and ±1 SD of six replicates.

Sample name	DI water (mV)	DI water + 5 mM NaCl (mV)	Fish medium (mV)	Seawater (mV)	Daphnia medium (mV)
Nanograin CeO2	33.0 ± 2.0	33.9 ± 1.7	−11.1 ± 1.0	N/A	1.2 ± 0.2
Nanosun ZnO	24.6 ± 0.4	25.2 ± 0.6	12.4 ± 0.3	N/A	4.9 ± 0.2
Micron ZnO	20.2 ± 0.4	13.9 ± 0.6	4.4 ± 0.4	N/A	−4.6 ± 0.4
Z-COTE ZnO	24.3 ± 0.4	20.8 ± 0.8	10.8 ± 0.1	N/A	1.3 ± 0.2
Micron CeO2	−7.0 ± 6.0	−2.0 ± 2.0	−22.3 ± 0.5	N/A	−15.0 ± 0.3
Ceria Dry CeO2	28.0 ± 2.0	23.0 ± 1.3	−15.3 ± 0.6	N/A	−17.4 ± 0.3