Multi-parameter magnetic resonance imaging based on NaGdF₄ nanoprobes for diagnosis of intraperitoneal tumors

Conventional imaging techniques often fall short in detecting intraperitoneal tumors, such as colon cancer and its metastases. These tumors are easily missed due to the limited diagnostic resolution of single-mode (T₁ or T₂) magnetic resonance imaging (MRI), which fails to provide comprehensive diagnostic information. To address this challenge, we developed an MRI dual-mode nanoparticle, NaGdF₄@PEG, which can simultaneously and sensitively enable both T₁ and T₂-weighted imaging thanks to its native properties. Extensive biosafety evaluations, including cytotoxicity tests and long-term in vivo toxicity studies, have demonstrated the excellent biocompatibility of NaGdF₄@PEG nanoparticles. For tumor diagnosis, NaGdF₄@PEG achieved an imaging window period of over 4 h and allowed for precise localization of tumors in dual-mode sequences due to the enhanced permeability and retention (EPR) effect of tumors. It also enabled the identification of tumor vasculature. Overall, NaGdF₄@PEG offers a highly effective strategy for multi-parameter tumor diagnosis.