Three-Dimensional Afterglow Luminescence–MRI Fusion Tomography with Magnetically Targeted Luminescent-Magnetic Nanoparticles for Deep-Seated Tumor Imaging

Optical imaging offers high sensitivity and specificity for noninvasive cancer detection, but conventional techniques suffer from limited probe accumulation, tissue autofluorescence, and poor depth resolution. Afterglow luminescence overcomes autofluorescence by emitting persistent light after excitation, yet its utility in vivo remains hindered by weak tumor enrichment and two-dimensional readouts lacking spatial context. Here, we report luminescent-magnetic nanoparticles (LM-NPs) coencapsulating luminescent trianthracene (TA) molecules and iron oxide cores within the amphiphilic polymer pluronic-F127. Under an external magnetic field, LM-NPs rapidly accumulate in tumors, amplifying the fluorescence- and light-induced afterglow signals and enhancing the tumor-to-tissue ratio. To recover three-dimensional tumor features, we introduce afterglow luminescence tomography (ALT), a reconstruction framework that fuses LM-NP afterglow data with MRI structural maps in a unified space. By modeling photon propagation via finite-element analysis and solving the inverse model with an alternating-direction method of the multipliers algorithm, ALT precisely localizes nanoparticle distributions in deep tissues, delineates lesion morphology and margins, and enables quantification of nanoparticles' uptake. We demonstrated the effect of three-dimensional reconstruction of ALT in subcutaneous, orthotopic glioma and pancreatic cancer mouse models, achieving superior depth penetration, sensitivity, and spatial resolution compared to planar methods. This nanoplatform, combining magnetic targeting, dual-excitation afterglow, and 3D tomography imaging, shows great promise for early cancer detection, intraoperative guidance, and longitudinal therapeutic monitoring.