Gadolinium-labelled iron/iron oxide core/shell nanoparticles as - contrast agent for magnetic resonance imaging.

Magnetic resonance imaging (MRI) is indispensable and powerful in modern clinical diagnosis and has some advantages such as non-invasiveness and high penetration depth. Furthermore, dual - MR imaging has attracted crucial interest as it can decrease the risk of pseudo-positive signals in diagnosing lesions. And it's worth nothing that the dual-mode MR imaging displays a vital platform to provide relatively comprehensive diagnosis information and receive accurate results. Herein, we report a dual - MR imaging contrast agent (CA) grounded on the iron/iron oxide core/shell nanomaterials conjugated with gadolinium chelate. The Gd-labeled Fe@FeO NPs reveal the feasibility to utilize them to serve as a dual - MR imaging CA, and the relaxivity results in a 0.5 T MR system showed a longitudinal relaxivity value ( ) and transverse relaxivity value ( ) of 7.2 mM s and 109.4 mM s, respectively. The MTT results demonstrate the Gd-labeled Fe@FeO NPs have no obvious cytotoxicity and a good compatibility. The and MRI generated a brighter effect and darkening in -weighted MR imaging and -weighted images, respectively. The results clearly indicate that Gd-labeled Fe@FeO NPs have potential as a magnetic resonance imaging contrast reagent.