Intrinsically zirconium-89-labeled manganese oxide nanoparticles for in vivo dual-modality positron emission tomography and magnetic resonance imaging

Manganese-based nanoparticles (NPs) have recently attracted much attention in the field of biomedical imaging due to their impressive enhanced T1 contrast ability. Although the reported manganese-based NPs have exhibited good imaging capabilities as contrast agents, it is still urgent to develop novel multifunctional manganese-based imaging probes for future biomedical imaging, especially PET/MRI probes. Herein, we present chelator-free zirconium-89 ( ⁸⁹ Zr, _t1/2 : 78.4 h) labeling of manganese oxide NPs (Mn ₃ O ₄ @PEG) with ∼78% labeling yield and good stability. Serial positron emission tomography (PET) and magnetic resonance imaging (MRI) studies non-invasively assessed the biodistribution patterns of the NPs and the feasibility of in vivo dual-modality imaging and lymph-node mapping. Since Mn ₃ O ₄ NPs exhibited desirable properties for enhanced T1 imaging and the simplicity of chelator-free radiolabeling, [ ⁸⁹ Zr]Mn ₃ O ₄ @PEG NPs offer a novel, simple, safe and accurate nanoplatforms for future precise cancer imaging and diagnosis.