Preparation Of Nanocomposites Based Cerium Dioxide And Their In Vitro Anti-tumor Activity

Cancer has become a global problem that affects people’s health.Traditional cancer treatment options include surgery,chemotherapy,radiotherapy,and combinations of these treatments.However,these treatment modalities have resulted in high clinical mortality due to problems such as tumor recurrence after surgery and side effects on healthy tissues.In recent years,new strategies such as photothermal therapy（PTT）,chemodynamic therapy（CDT）,and photodynamic therapy（PDT）have been reported.These approaches are not only effective in killing tumor cells,but also have obvious advantages such as less toxicity and fewer side effects.Combination therapy is a combination of the advantages of a single treatment to better improve the effectiveness of tumor treatment.The emergence of combination therapy has provided new options for cancer treatment.In this paper,three kinds of nano-composites based on cerium dioxide were designed for PTT-CDT combined therapy.The main contents are as follows:（1）PPy@CeO₂ NPs was designed and synthesized for PTT-CDT combined tumor therapy.The nanoparticle were loaded with CeO₂ NPs on the surface of polypyrrole nanoparticle（PPy NPs）.As an organic polymer,PPy NPs have good photothermal properties.CeO₂ NPs can kill cells by generating hydroxyl radicals through Fenton-like reactions.The combination of PPy NPs and CeO₂ NPs can combine the advantages of the both in treatment,so as to achieve better therapeutic effect.The photothermal temperature of PPy@CeO₂ NPs（100μg/m L）reached 58℃in vitro under near infrared light irradiation.In vitro antitumor experiments showed that the survival rate of tumor cells was 24.3%,indicating the potential of PPy@CeO₂ NPs in tumor therapy.（2）CeO₂@MnO₂@ICG composite nanomaterials were designed and synthesized for photothermo-chemodynamic combined tumor therapy.In this work,porous CeO₂ hollow spheres were synthesized by self-template method,and MnO₂ particles were coated on the surface of porous CeO₂ hollow spheres to improve the ability of the composite to catalyze hydrogen peroxide to produce hydroxyl free radicals.Finally,CeO₂@MnO₂@ICG composite nanomaterials were obtained by loading ICG.CeO₂@MnO₂@ICG composite nanomaterial（200μg/m L）in vitro photothermal temperature reached 51.9℃,in vitro experiment showed that the survival rate of tumor cells was 18.3%.CeO₂@MnO₂@ICG composite nanomaterials provided a new strategy for tumor combination therapy.（3）CCPF NPs（CeO₂@CuS@PDA-FA NPs）were designed and synthesized for PTT-CDT combination therapy.The nanoparticles were loaded with CuS NPs on the surface of CeO₂ NPs,then polydopamine（PDA）was encapsulated on the surface of CeO₂@CuS NPs,and finally coupled with folic acid（FA）and PDA.CCPF NPs（200μg/m L）reached a photothermal temperature of 52.2℃under near-infrared red light irradiation,and in an in vitro cell experiment,compared with the control group,the tumor cell The survival rate was only 7%,achieving a better therapeutic effect.