Preparation of Dye Molecule‐Intercalated MoO₃ Organic/Inorganic Superlattice Nanoparticles for Fluorescence Imaging‐Guided Catalytic Therapy

Intercalation of organic molecules into the van der Waals gaps of layered materials allows for the preparation of organic/inorganic superlattices for varying promising applications. Herein, the preparation of a series of dye molecule/MoO₃ organic/inorganic superlattice nanoparticles by aqueous intercalation of several dye molecules into layered MoO₃ for fluorescence imaging-guided catalytic therapy is reported. The long MoO₃ nanobelts are treated by ball milling and subsequent aqueous intercalation followed by a cation ion exchange to obtain the dye molecule-intercalated MoO₃ organic/inorganic superlattices. Importantly, because of the activation induced by organic intercalation, the Nile blue (NB)-intercalated MoO_3-_x (NB-MoO_3-_x ) nanoparticles show excellent catalytic activity for the generation of reactive oxygen species, that is, hydroxyl radical (·OH) and superoxide anion (·O₂^- ), through catalyzing H₂ O₂ and O₂ , respectively. Moreover, the intense fluorescence of the intercalated NB molecules endows NB-MoO_3-_x with the in vivo fluorescence imaging capability. Thus, the polyvinylpyrrolidone-modified NB-MoO_3-_x nanoparticles can be used for tumor-specific catalytic therapy to realize efficient cancer cell elimination in vitro and fluorescence imaging-guided tumor ablation in vivo.