Surface and Interfacial Engineering of Iron Oxide Nanoplates for Highly Efficient Magnetic Resonance Angiography

Magnetic resonance angiography using gadolinium-based molecular contrast agents suffers from short diagnostic window; relatively low resolution and risk of toxicity. Taking into account the chemical exchange between metal Centers and surrounding protons; magnetic nanoparticles with suitable surface and interfacial features may serve as alternative T-1 contrast agents. Herein, we report the engineering on surface structure of iron oxide nanoplates to boost T-1 contrast ability through synergistic effects between exposed metal-rich Fe3O4(100) facets and embedded Gd2O3 clusters. The nanoplates show prominent T-1 contrast in a wide range of magnetic fields with an ultrahigh r(1) value up to 61.5 MM-1 s(-1). Moreover, engineering on nanobio interface through zwitterionic molecules adjusts the in vivo behaviors of nanoplates for highly efficient magnetic resonance angiography with steady-state acquisition Window, Superhigh resolution in vascular details, and low toxicity. This study provides a powerful tool for sophisticated design of MRI contrast agents for diverse use in bioimaging applications.