Biocompatible PEGylated MoS₂ nanosheets: Controllable bottom-up synthesis and highly efficient photothermal regression of tumor

Two-dimensional transition metal dichalcogenides, particularly MoS₂ nanosheets, have been deemed as a novel category of NIR photothermal transducing agent. Herein, an efficient and versatile one-pot solvothermal synthesis based on "bottom-up" strategy has been, for the first time, proposed for the controlled synthesis of PEGylated MoS₂ nanosheets by using a novel "integrated" precursor containing both Mo and S elements. This facile but unique PEG-mediated solvothermal procedure endowed MoS₂ nanosheets with controlled size, increased crystallinity and excellent colloidal stability. The photothermal performance of nanosheets was optimized via modulating the particulate size and surface PEGylation. PEGylated MoS₂ nanosheets with desired photothermal conversion performance and excellent colloidal and photothermal stability were further utilized for highly efficient photothermal therapy of cancer in a tumor-bearing mouse xenograft. Without showing observable invitro and invivo hemolysis, coagulation and toxicity, the optimized MoS₂-PEG nanosheets showed promising invitro and invivo anti-cancer efficacy.