Table 3.
Relaxometry analysis at 37 °C of NPFe@FeOx@SiO2, NPFe@FeOx@SiO2-PEG, and RESOVIST® at 20 MHz and 60 Hz. Values at 400 MHz were deduced from the contrast observed in the phantom images.
| Frequency. | Relaxivity (mM−1.s−1) | NPs* 2 weeks Old |
NPs*-PEG 2 weeks Old |
NPs* 2 months Old |
NPs*-PEG 2 months Old |
RESOVIST® Experimental |
DOTAREM® Experimental |
|---|---|---|---|---|---|---|---|
| 20 MHz | r1 | 9.5 ± 0.5 | 9.8 ± 0.5 | 8.9 ± 0.4 | 3.6 ± 0.2 | 25.0 ± 1.3 | 4.1 ± 0.2 |
| r2 | 165.5 ± 8.3 | 186.5 ± 9.3 | 163.1 ± 8.2 | 181.7 ± 9.1 | 161.8 ± 8.1 | 4.9 ± 0.2 | |
| r2/r1 | 17.5 | 19 | 18.3 | 50 | 6.5 | 1.2 | |
| 60 MHz | r1 | 3.1 ± 0.2 | 2.5 ± 0.1 | 3.5 ± 0.2 | 1.30 ± 0.07 | 11.0 ± 0.6 | 3.7 ± 0.2 |
| r2 | 166.0 ± 8.3 | 188.0 ± 9.4 | 175.0 ± 8.8 | 185.1 ± 9.3 | 157.8 ± 7.9 | 4.0 ± 0.2 | |
| r2/r1 | 55.3 | 75.2 | 50 | 142 | 14.3 | 1.08 | |
| 400 MHz | r2 | 208.0 ± 10.4/237.0 ± 11.9 | 254.0 ± 12.7 | 224.0 ±11.2 | 239.0 ± 12.0 | 232.0 ± 11.6 | 4.7 ± 0.2 |
NPs*: NPFe@FeOx@SiO2.