Figure 5.

Room temperature NMR relaxation rates R₁ (a) and R₂ (b) measurements as a function of iron concentration c(Fe) of as-synthesized, centrifuged, and BSA-coated MNP measured at 1.5 T. The relaxation rates are obtained by linear regression and drawn as straight lines; the corresponding for the r₁ and r₂ values are listed in Table 1.