Lanthanide Complexes-Doped Silica Nanoparticles for Dual-Modal Ratiometric Time-Gated Luminescence/Magnetic Resonance Imaging of Inflammatory Diseases

Inflammation plays a pivotal role in various diseases, and a key biomarker of inflammation is hypochlorous acid (HClO), an upregulated reactive species that can cause extensive tissue damage. Accurate detection of HClO is essential for enhancing disease diagnosis and treatment management. Here, we report rationally designed lanthanide complex-doped nanoparticles (DNPs) for ratiometric time-gated luminescence (RTGL)/ magnetic resonance (MR) imaging of HClO. The DNPs nanoprobe consists of binuclear β-diketone-Eu3+-DO3A-Gd3+ complexes covalently conjugated to the surface of silica nanoparticles encapsulating PTTA-Tb3+ complexes. The DNPs magnetoluminescent silica nanoparticles combine the advantages of both RTGL and MR detection modes, enabling high accuracy and sensitivity across a wide range of resolutions from subcellular to whole-body imaging. The prepared nanoprobe showed a rapid, sensitive, and selective RTGL (I539/I607) response, along with MR turn-off response to HClO. Its applicability was demonstrated through RTGL imaging of HClO in live cells and zebrafish as well as bimodal RTGL/MR imaging of HClO in a mouse model of acute liver inflammation. These findings highlight the potential of DNPs for the diagnosis and monitoring of inflammation.