Table 1.

In vitro Transverse relativities ($r_2$ ) of MRI contrast agents.

	${\mathit{r}}_2\left[{\mathbf{mM}}^{-1}{\mathbf{S}}^{-1}\right]$
Fe3O4@SiO2@HPG	8.87
Fe3O4@SiO2@HPG-FA	23.25
Fe3O4@HPG	0.029
Fe3O4@HPG-FA	0.131