Intrinsically Zr-labeled GdOS:Eu nanophosphors with high stability for dual-modality imaging.

Radioluminescence imaging (RLI) employs high energy particles from radioisotope decay for excitation of selected nanophosphors. Co-injection of radiopharmaceuticals and nanophosphors suffers from suboptimal RL efficiency owing to the large separation between the source and the emitter. In addition, vastly different pharmacokinetic profiles of the two further impede the practical applications of this approach. To overcome the above challenges, chelator-free radiolabeled nanophosphors with excellent RL efficiency and dual-modality imaging capabilities have been proposed. Abundant O donors on GdOS:Eu could intrinsically chelate oxophilic radionuclide Zr with ~80 % labeling yield. Positron emission tomography demonstrated superb long-term radiostability of [Zr]GdOS:Eu@PEG nanoparticles , and a conventional optical imaging system was used to study radiouminescence properties of [Zr]GdOS:Eu@PEG nanoparticles and .