Liquid Metal-Enabled Microspheres with High Drug Loading and Multimodal Imaging for Artery Embolization

Abstract

The drug-eluting microspheres that have been widely used in clinical treatments such as chemoembolization commonly suffer from inadequate drug loading and tracking difficulties. With inherent high density and excellent biocompatibility, liquid metal (LM) has been explored at the frontiers of medical imaging and clinical therapy. Herein, multifunctional microspheres (SA/LM/DOX) are reported with high drug loading and multimodal imaging by adsorbing silanized LM particles on sulfonated agarose microspheres (SA), which are capable of heating and accelerating drug release under an 808 nm near-infrared (NIR) laser. The negative SA microspheres can adsorb more positive drugs such as doxorubicin (DOX) up to 104 mg DOX per mL microspheres. It deserves to be mentioned that SA/LM/DOX microspheres have the function of multimodal imaging under computed tomography (CT), magnetic resonance imaging (MRI), and B-scan ultrasonography (US), which significantly facilitate location tracking during the embolization process. In rabbit ear central artery embolization, these microspheres are smoothly injected into the intended location of the vessel and successfully blocked blood flow, and eventually led to necrosis of rabbit ear. Overall, these microspheres with high drug loading capacity and multimodal contrast properties are promising candidates to be developed as new products for future clinical medicine.