Fig. 3From: PDGFB-targeted functional MRI nanoswitch for activatable T1–T2 dual-modal ultra-sensitive diagnosis of cancera M-H hysteresis loops of Fe3O4, FS, and FMS at 300 K. b Grayscale T2WI, and c pseudocolor T2WI, and d corresponding r2 values of Fe3O4, FS, and FMS. e TEM images, f T1WI and T2WI, g r1 values, h r2 values, and i M-H hysteresis loops at 300 K of FMS-1 to FMS-5Back to article page