Synthesis Of UCNPs@MS-PS-MnO₂ And MoO_x-PEG-Au₂₅ And Study On Anti-tumor Performance

In recent years,photothermal therapy,photodynamic therapy and other non-invasive treatments have become popular in research of new ways forclinical cancer therapy.Usinglight-sensitive nanomaterials to produce thermal radiation or single-line oxygen to achieve tumor treatment with near-infrared lightsis of non-tolerance,higher treatment efficiency and fewer side effects.Rare earth upconversion nanoparticles are often used for the diagnosis and treatment of cancer due to their outstanding imaging performance.Mesoporous materials and nanospheresare often utilized as carriers of photosensitizers and drugs due to their large specific surface areas.In addition,with the synthesis of multi-functional nano-materials,co-therapy of several treatment methods has become a major development direction of cancer treatment.The main contents of this paper are as follows:The upconversion nanoparticles were prepared with the method of high temperature pyrolysis,and the photosensitizers were loaded on the surface of the mesoporous silica layer.The manganese dioxide nanosheets were complexed to attain the final UCNPs@MS-PS-MnO_2.The core-shellmicrostructures of nanoparticles were characterized by XRD and TEM tests.FTIR and UV-Vis indicated that MnO₂nanosheets were successfully synthesized on the surface of nanoparticles.UCL,CT and MRI were used to test the multi-mode imaging effects and the photodynamic therapy was successfully completedin 980 nm near infrared light.In addition,the effect of photodynamic therapy was obviously enhanced in the presence of the MnO₂nanosheets.MoO_x nanosheets were synthesized with the hydrothermal method and modified water-soluble using the self-synthesized C₁₈PMH-PEG.The average size of the nanosheets,the ideal drμg carriers,was 135 nm and the thickness was less than 5 nm.What’s more,the MoO_x-PEG nanosheets can be self-degraded in neutral and acidic environments,and of good biocompatibility.The prepared gold nanoclusters were loaded onto the surface of the nanosheets by electrical adsorption.MoO_x nanosheets and gold clusters respectively showed outstanding photothermolysis and photosensitivity in 808 nm near infrared light,which successfμlly realized synergistic workof photothermal and photodynamic therapy.