Fig. 1

Schematic illustration of the synthesis and tumor-inhibiting mechanism of Au-Pt@ur NPs. (a) The Synthesis of Au-Pt NPs: Briefly, the Au NP served as the core for the surface deposition of Pt atoms to form Au-Pt NPs. Ureases were then covalently immobilized onto Au-Pt NPs via HS-PEG₂₀₀₀-NH₂Cl linker. (b) The Tumor-inhibiting Mechanism of Au-Pt NPs: after intravesical administration, Au-Pt@ur NPs gained the power for self-propulsion via catalyzing urea in the bladder cavity and hydrogen peroxide in the tumor microenvironment, thus deeply penetrating the tumor. The NIR irradiation activated the photothermal effect of Au-Pt@ur NPs, together with the induction of significant reactive oxygen species (ROS), to ablate tumors