Table 1. Primary Size, Hydrodynamic Size and Zeta-potential of 24 Metal Oxide Nanoparticles.
| Number | MOx | Primary Size (nm)a |
Hydrodynamic Size (nm)b |
Zeta-potential (mV)c |
|---|---|---|---|---|
| 1 | Al2O3 | 14.7±5.2 | 524.8 ± 32.8 | −24.0 ± 0.5 |
| 2 | CeO2 | 12.8 ± 3.4 | 321.3 ± 8.6 | −28.9 ± 3.3 |
| 3 | CoO | 18.3 ± 6.8 | 378.3 ± 16.4 | −25.5 ± 1.3 |
| 4 | Co3O4 | 10.0 ± 2.4 | 247.6 ± 16.9 | −29.0 ± 2.2 |
| 5 | Cr2O3 | 71.8 ±16.2 | 478.5 ± 7.2 | −26.2 ± 3.1 |
| 6 | CuO | 193.0 ± 90.0 | 289.5 ± 31.0 | −26.9 ± 0.8 |
| 7 | Fe2O3 | 12.3 ± 2.9 | 385.2 ± 6.3 | −24.1 ± 2.0 |
| 8 | Fe3O4 | 12.0 ± 3.2 | 831.7 ± 41.8 | −27.0 ± 2.3 |
| 9 | Gd2O3 | 43.8 ± 15.8 | 726.7 ± 54.8 | −34.7 ± 0.7 |
| 10 | HfO2 | 28.4 ± 7.3 | 349.9 ± 5.2 | −24.3 ± 2.1 |
| 11 | In2O3 | 59.6 ± 19.0 | 303.2 ± 5.2 | −35.5 ± 2.4 |
| 12 | La2O3 | 24.6 ± 5.3 | 471.2 ± 20.9 | −27.8 ± 0.6 |
| 13 | Mn2O3 | 51.5±7.3 | 525.9 ± 7.8 | −30.9 ± 0.4 |
| 14 | NiO | 13.1 ± 5.9 | 277.5 ± 23.0 | −23.1 ± 2.0 |
| 15 | Ni2O3 | 140.6 ± 52.5 | 665.8 ± 46.4 | −24.4 ± 2.2 |
| 16 | Sb2O3 | 11.8 ± 3.3 | 459.9 ± 22.7 | −25.8 ± 0.9 |
| 17 | SiO2 | 13.5 ± 4.2 | 374.9 ± 29.0 | -16.8 ± 2.0 |
| 18 | SnO2 | 62.4 ± 13.2 | 635.0 ± 52.0 | −26.4 ± 0.3 |
| 19 | TiO2 | 12.6 ± 4.3 | 497.0 ± 17.1 | −31.5 ± 1.4 |
| 20 | WO2 | 16.6 ±4.3 | 511.9 ± 19.4 | −23.3 ± 1.1 |
| 21 | Y2O3 | 32.7 ±8.1 | 594.5 ± 33.0 | −27.6 ± 0.4 |
| 22 | Yb2O3 | 61.7 ± 11.3 | 682.6 ± 56.2 | −29.7 ± 0.5 |
| 23 | ZnO | 22.6 ± 5.1 | 379.0 ± 11.0 | −27.0 ± 1.1 |
| 24 | ZrO2 | 40.1 ± 12.6 | 384.4 ± 25.0 | -19.7 ±3.6 |
a
Primary size of the particles in their dry state was obtained by transmission electron microscopy (JEOL, 1200 EX).
b
Hydrodynamic size was determined by high throughput dynamic light scattering (HT-DLS, Dynapro Plate Reader, Wyatt Tech).
c
Particle ζ-potential was measured using ZetaPALS (Brookhaven Instruments, Holtsville, NY). Introduction of the nanoparticles in Holtfreter’s medium (pH 7.0) did not significantly change the medium pH in spite of the dissolution of metal oxide nanoparticles.