Fe₃O₄-based Nanocomposites With Enhanced Photothermal Effect For Combined Cancer Therapy

Cancer has seriously threatened human health and life.In many cases,single-modality therapy approach cannot satisfy high therapeutic efficacy.It is important and necessary to combine multiple modalities and achieve superadditive therapy.Thus,we optimized the composition and structure based on the biocompatible Fe₃O₄ nanomaterials.The Fe₃O₄-IR806superparticles and the Fe₃O₄ superparticle@mSiO₂ were synthesized,respectively.Their application in photothermal-photodynamic therapy and photothermal-chemotherapy were explored.The main research contents are as follows:1.The Fe₃O₄-IR806 superparticles were constructed by introducing photosensitizer IR806.The Fe₃O₄-IR806 superparticles had photothermal effects and generated reactive oxygen species?ROS?with the illumination of near-infrared?NIR?light.The introduction of the IR806 and the fabrication of the self-assembled structure warrant 3.5 times increase in photothermal effect compared with the Fe₃O₄ nanoparticles.The photothermal effect of the Fe₃O₄-IR806 superparticles depended on the concentration and the incident laser density.The Fe₃O₄-IR806 superparticles exhibited negligible toxicity.The Fe₃O₄-IR806 superparticles efficiently inhibited the cultured glioma cells via photothermal ablation and ROS cytotoxicity in vitro,as well as suppressed the bearing glioma growth in vivo with the NIR light exposure.The research opens up a new way to construct therapeutic agents applied for photothermal-photodynamic therapy.2.The Fe₃O₄ superparticle@mSiO₂ with adjustable shell thickness were prepared by coating mesoporous SiO₂ on the surface of Fe₃O₄ superparticles.The coating of SiO₂ and the construction of mesoporous structure increased the photothermal effect of Fe₃O₄superparticles.The thicker the mesoporous SiO₂ shell,the higher the concentration or the laser power density,the better the photothermal performance.The drug loading efficiency of the Fe₃O₄ superparticle@mSiO₂ was 91.9%,which is higher than most reports.With the control of NIR light,the Fe₃O₄ superparticle@mSiO₂ efficiently killed the cultured glioma cells via photothermal-chemotherapy.The study provides an important theories and references for the design and construction of highly efficient photothermal-chemotherapy agents.