An amphiphilic lanthanide complexes-based liposome nanoprobe for dual-model time-gated luminescence and magnetic resonance imaging of hypochlorous acid in vitro and in vivo

The combination of complementary time-gated luminescence (TGL) and magnetic resonance (MR) imaging methods has become a powerful bioimaging tool. This study introduces a liposome nanoprobe, BHHBSB-Eu/Gd NPs, designed for bimodal TGL/MR imaging of hypochlorous acid (HClO) in vitro and in vivo. The BHHBSB-Eu/Gd NPs consist of amphiphilic β-diketone Eu³⁺/Gd³⁺ complexes that self-assemble into nanoparticles in aqueous solution. Due to the selective oxidation and decomposition of these β-diketone Eu³⁺/Gd³⁺ complexes by HClO, the magnetoluminescent nanoparticles, BHHBSB-Eu/Gd NPs, exhibit a rapid and specific response to HClO through HClO-triggered quenching of Eu³⁺ luminescence and a decline in MR relaxivity of the Gd³⁺ complex. By combining the subcellular resolution, high sensitivity and selectivity of TGL imaging with the unlimited depth penetration of MRI, the nanoprobe provides a robust tool for sensing and tracking HClO in vitro and in vivo. The nanoprobe was successfully used for TGL imaging of exogenous and endogenous HClO in living cells and zebrafish, as well as for bimodal TGL/MR imaging of HClO in a mouse model of drug-induced liver inflammation. These findings highlight the potential of BHHBSB-Eu/Gd NPs for the diagnosis and monitoring of inflammation.