Nanoplatforms with synergistic redox cycles and rich defects for activatable image-guided tumor-specific therapy

Abstract

<h2>Summary</h2> Multifunctional nanoplatforms for the early diagnosis and treatment of deep-seated tumors with high specificity are particularly desirable but face many challenges. Herein, nanoplatforms containing copper/manganese chalcogenide nanoflowers (CMC NFs) and ¹⁹F probes have been developed, which exhibit enhanced therapeutic efficiency and activatable ¹⁹F magnetic resonance imaging (MRI) capability within a tumor microenvironment (TME). CMC NFs containing synergistic redox pairs (Cu^ox/Cu^red, Mn^ox/Mn^red) and rich defects acted as integrated cascade enzyme mimics to effectively destroy the redox homeostasis of tumors via generation of reactive oxygen species (ROS) and GSH depletion. In addition, the ¹⁹F MRI signal could be switched on by attenuation of the paramagnetic relaxation enhancement (PRE) effect under TME conditions, affording a TME-activatable ¹⁹F MRI-guided tumor-specific chemodynamic therapeutic. These nanoplatforms could simultaneously boost therapeutic efficacy and regulate signal output, exhibiting significant potential for <i>in vivo</i> drug tracking and deep-seated tumor diagnosis and treatment.