Imaging Characteristics of USPIO Nanoparticles (<5 nm) as MR Contrast Agent In Vitro and in the Liver of Rats

<div>Relaxation profiles of USPIO nanoparticles with varying concentration. (a) T1-weighted and T2-weighted images of USPIO nanoparticles in saline solution (0.9% sodium chloride) with different iron concentrations from 0.1 mM to 1.5 mM. (b) The change of mean T1- and T2-weighted signal intensity as the iron concentration. (c) The relationship of longitudinal relaxation rate and iron concentration and the derived r1 relaxivity 0.556 mM−1·s−1. (d) The relationship of transversal relaxation rate and iron concentration and the derived r2 relaxivity 7.55 mM−1·s−1.</div>

Contrast Media & Molecular Imaging

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Figure 2

Figure 2: Imaging Characteristics of USPIO Nanoparticles (<5 nm) as MR Contrast Agent In Vitro and in the Liver of Rats