Fig. 8

Evolution of the degradation of the APS, DEX and DMSA coated MNPs in the liver measured at different times by AC magnetic susceptibility. The magnetic susceptibility profiles of the liver in mice to which the different MNPs were administered: a, APS-MNPs; b, DEX-MNPs; and c, DMSA-MNPs. The different degradation times after the last dose administered are represented in the following colors: 7 days (purple), 14 days (cyan), 1 month (pink), 3 months (orange), 6 months (blue), 9 months (green), 12 months (black) and finally, 15 months (gray). The in-phase (real, χ′- on the left) and out-of-phase (imaginary, χ′′- on the right) components of the AC magnetic susceptibility measurements are shown. The inset in the upper left corner of the χ′ profile shows the paramagnetic contribution observed at very low temperatures