Development of Ga-68 radiolabeled DOTA functionalized and acetylated PAMAM dendrimer-coated iron oxide nanoparticles as PET/MR dual-modal imaging agent

Gallium-68 radiolabeled DOTA- acetyl-PAMAM coated iron oxide nanoparticles (NPs) were developed as dual-modality agents for PET-MR imaging. The increase in the chelator content, acetylation step, and radiolabeling condition had distinctive effects on the physical, biological, and radiochemical properties of NPs. The r2 relaxivity coefficient value of the NPs was 96.7 mM−1s−1. High accumulation of candidate NPs was in the liver and spleen and about 3.4% ID/g uptake (tissue sampling), and a distinctive uptake (PET-CT image) were observed in the tumor site. These NPs could be used as the dual-modality agent for the diagnosis of the tumors via PET-MR imaging.