Figure 9.
(A) T2-weighted images of mice preinjection, and 0.1 h and 24 h post-MNP administration, highlighting the liver (yellow), spleen (red), and kidney (green). (B) Biodistribution of MNPs with different hydrodynamic diameters, in the liver (black), spleen (gray) and kidney (white); formulation A (86 nm) is approximately twice the size of formulation B (37 nm). While both formulations predominantly distribute in the liver and spleen, with minimal renal involvement, A shows gradual clearance from liver about 0.5 h postinjection, whereas B continues to accumulate in liver 1 h postinjection. Note: the height of the relative contrast intensity is only qualitative and depends on both iron oxide concentration and T2-relaxivity (r2/mM Fe/s) of MNPs (see Table 2).