Novel Carbon Nanohybrids As Highly Efficient Magnetic Resonance Imaging Contrast Agents

Gadofullerenes derivatives had been proved to exhibit high relaxivities, even higher than that of commercial Gd-DTPA contrast agents. However, all reported gadofullerene contrast agents were based on the functionalized metallofullerene. In this presentation, we successfully constructed novel water-soluble carbon nanohybrids based on unmodified metallofullerene and graphene oxide, which exhibited high relaxivity and better brightening effect in magnetic resonance (MR) imaging in vivo. Gd@C₈₂ was produced and isolated by the industrial-scale production line of metallofullerenes firstly established in Institute of High Energy Physics, Chinese Academy of Science (CAS). A “secondary spin-electron transfer” relaxation mechanism was proposed to explain how the encaged Gd³⁺ ions of carbon nanohybrids interact with the surrounding water molecules. This approach opens new opportunities in developing highly efficient and low toxic MRI contrast agent.