Table 1.
Physico-chemical characteristics of the TiO 2 -NP suspensions a
| Dispersant | Water | Gastric | Intestinal | Ringer + FBS | cDMEM |
|---|---|---|---|---|---|
| Z-average (nm)b |
132.0 ± 0.8 |
218.4 ± 2.9 |
> 1000 |
352.0 ± 0.9 |
320.5 ± 1.8 |
| PdIc |
0.188 |
0.330 |
> 0.5 |
0.298 |
0.290 |
| ζ (mV)d | 20.0 ± 0.6 | 30.6 ± 2.7 | -21.3 ± 0.7 | -13.2 ± 1.2 | -10.8 ± 0.6 |
aDLS measurements of a 50 μg/mL TiO2-NP suspension prepared either in water (“Water”), in the gastric phase (“Gastric” i.e. pepsin/HCl, pH2), in the intestinal phase (“Intestinal”, i.e. pepsin/HCl, pancreatin and bile extracts, pH7), in ex vivo exposure medium (“Ringer + FBS” i.e. Ringer solution, 10% (v/v) fetal bovine serum (FBS), pH7.4) or in in vitro exposure medium (cDMEM, i.e. Dulbecco Modified Medium (DMEM), 10% (v/v) FBS, pH7.4). bZ-average hydrodynamic diameter extracted by cumulant analysis of the data. cPolydispersity index (PdI) from cumulant fitting. dζ: zeta potential.