Fig. 4
Magnetic resonance imaging of size-isolated SPION. MRI of the crude, C1–C5, Resovist® and Sinerem® samples upon characterization on a 3 T clinical scanner. a T1- and T2-weighted MR images of the samples at a concentration of 0.01 mM. MR images for other SPION concentrations are provided in Additional file 1: Figure S8. b and c Longitudinal (r1) and transversal (r2) relaxivities of the samples in water. Values represent average ± standard deviation of three independent samples