Combined Positron Emission Tomography and Cerenkov Luminescence Imaging of Sentinel Lymph Nodes Using PEGylated Radionuclide-Embedded Gold Nanoparticles

New imaging probes with high sensitivity and stability are urgently needed to accurately detect sentinel lymph nodes (SLNs) for successful cancer diagnosis. Herein, the use of highly sensitive and stable PEGylated radionuclide‐embedded gold nanoparticles (PEG‐RIe‐AuNPs) is reported for the detection of SLNs by combined positron emission tomography and Cerenkov luminescence imaging (PET/CLI). PEG‐RIe‐AuNPs show high sensitivity and stability both in vitro and in vivo, and are not toxic to normal ovarian and immune cells. In vivo PET/CLI imaging clearly reveals SLNs as early as 1 h post PEG‐RIe‐AuNP‐injection, with peak signals achieved at 6 h postinjection, which is consistent with the biodistribution results. Taken together, the data provide strong evidence that PEG‐RIe‐AuNPs are promising as potential lymphatic tracers in biomedical imaging for pre and intraoperative surgical guidance. PEGylated radionuclide‐embedded gold nanoparticles with excellent sensitivity and stability as new multimodal imaging platform are successfully applied to detect sentinel lymph nodes by the use of combined positron emission tomography and Cerenkov luminescence imaging, suggesting the strong feasibility of PEG‐RIe‐AuNPs as potential lymphatic tracers in the clinical setting.