2D LDH-MoS₂ clay nanosheets: synthesis, catalase-mimic capacity, and imaging-guided tumor photo-therapy

Owing to the hypoxia status of the tumor, the reactive oxygen species (ROS) production during photodynamic therapy (PDT) of the tumor is less efficient. Herein, a facile method which involves the synthesis of Mg-Mn-Al layered double hydroxides (LDH) clay with MoS₂ doping in the surface and anionic layer space of LDH was presented, to integrate the photo-thermal effect of MoS₂ and imaging and catalytic functions of Mg-Mn-Al LDH. The designed LDH-MoS₂ (LMM) clay composite was further surface-coated with bovine serum albumin (BSA) to maintain the colloidal stability of LMM in physiological environment. A photosensitizer, chlorin e6 (Ce6), was absorbed at the surface and anionic layer space of LMM@BSA. In the LMM formulation, the magnetic resonance imaging of Mg-Mn-Al LDH was enhanced thanks to the reduced and acid microenvironment of the tumor. Notably, the ROS production and PDT efficiency of Ce6 were significantly improved, because LMM@BSA could catalyze the decomposing of the overexpressed H₂O₂ in tumors to produce oxygen. The biocompatible LMM@BSA that played the synergism with tumor microenvironment is a promising candidate for the effective treatment of cancer.