Table 4.
Performance characteristics for the spICP-MS analysis of E171. ESD: equivalent spherical diameter.
| ESD | Particle Mass Concentration | Particle Number Concentration | |
|---|---|---|---|
| Repeatability within five series of three repeats (relative standard deviation in percent of average; %) | 4.9 | 18 | 17 |
| Reproducibility between five series (relative standard deviation in percent of average; %) | 8.2 | 23 | 13 |
| Size detection limit (nm) | 39 | - | - |
| Concentration detection limit (ng/L or particles/L) 1 | - | 50 | 200 |
| Relative recovery compared (%) | 107 | 96 | - |
| Uncertainty budget for the mean of three repeats analyzed on a single day | |||
| Repeatability uncertainty (%) | 2.8 | 10 | 10 |
| Between-day uncertainty (%) | 6.5 | 23 | 13 |
| Trueness uncertainty (%) | 5.1 | 11 | 7 |
| Combined measurement uncertainty (%; k = 1) | 8.8 | 27.5 | 18 |
| Expanded measurement uncertainty (%; k = 2) | 18 | 55 | 36 |
1 Concentration detection limit expressed in the diluted dispersion.