Synchronous PET/MR imaging and visualizing penetration of nanomedicine within tumor based on ⁶⁸Ga-NaGdF₄ probes

Magnetic resonance imaging (MRI) and nuclear medicine imaging are widely used for cancer detection due to their high soft tissue resolution and sensitivity. Each modality has inherent limitations; therefore, integrated techniques such as positron emission tomography/magnetic resonance (PET/MR) have been developed. However, achieving simultaneous signal enhancement for both PET and MRI in clinical settings remains challenging. In this study, we employed gallium-68 (⁶⁸Ga)-labelled NaGdF₄@RGD nanoprobes as a model system to establish a synchronous PET/MR imaging strategy for tumor diagnosis. These nanoprobes exhibited suitable radiochemical half-life, and effective tumor-associated targeting, enabling successful PET/MR imaging across multiple tumor models, including hepatoma, renal cancer, and breast cancer in vivo. Notably, this imaging strategy allowed time-resolved visualization of nanoprobe distribution and prolonged retention behavior in orthotopic liver tumors during delayed imaging periods, providing imaging-based insights into nanomedicine pharmacodynamics.