Two-step in vivo tumor targeting by biotin-conjugated antibodies and superparamagnetic nanoparticles assessed by magnetic resonance imaging at 1.5 T.

Purpose The purpose of this study was to assess two-step in vivo tumor targeting by specific biotin-conjugated antibodies and ultrasmall superparamagnetic iron oxide (USPIO)-anti-biotin nanoparticles as contrast agents for magnetic resonance imaging (MRI) at 1.5 T.