Figure 5.
Long circulating bimodal nanoparticles for PET-MR and SPECT-MRI. (A) Bisphosphonate anchors allow strong and stable binding of PEG polymers and radionuclides on the surface of the USPIOs; (B) The bimodal nanoparticles circulate in the bloodstream, as indicated by the strong imaging signal in the heart and vessels. The compound can be detected using radionuclide imaging and T1-MRI. Negligible uptake in the reticuloendothelial system was detected.12 PET, positron emission tomography; MRI, magnetic resonance imaging; USPIOs, ultra-small superparamagnetic iron oxide.