NIR-II Photoresponsive Magnetoliposomes for Remote-Controlled Release and Magnetic Resonance Imaging.

Magnetic nanoparticles, especially iron oxide nanoparticles, have become versatile and widely used tools in nanomedicine due to their unique magnetic properties, biocompatibility, and tunable functionality. Liposomes have further enhanced the potential of iron oxide nanoparticles by serving as effective nanocarriers with advantages such as drug coencapsulation and enhanced molecular imaging properties. In this study, we present magnetoliposomes composed of ultrasmall free-floating iron oxide nanoparticles inside liposomes (LP-IONPs) and thermoresponsive phospholipids, which were designed as dual T₂-T₁ magnetic resonance imaging (MRI) contrast agents for image-guided liposome degradation and infrared light-responsive nanocarriers in the second biological window for remote-controlled drug delivery. We demonstrated a dynamic shift from T₂ to T₁ MRI contrast during intracellular degradation of LP-IONPs, along with successful light-activated drug release in cancer cells. Biodistribution studies using MRI and histological analysis confirmed their potential for in vivo applications. These results highlight the potential of LP-IONPs as image-guided and remote-controlled drug delivery systems.