Preparation,modification And Anti-tumor Performance Of Manganese-doped Single Atom Catalyst

In view of the obvious toxic and side effects in the traditional tumor treatment process and the greater harm to the human body,the use of nanomaterials to achieve endogenous destruction of tumors through enzyme catalyzed therapy,chemical dynamic therapy,photothermal therapy and other means has gradually become a hot field of research.In recent years,single atom catalysts have been used in the study of chemodynamic therapy of tumors due to their excellent catalytic ability,which can effectively utilize the tumor microenvironment to kill tumors.Based on this,this thesis designs two single atom catalyst therapeutic platforms to study their tumor therapeutic performance and biological effects.First,the construction of polyethylene glycol modified manganese-doped single atom catalyst(PSMC)and its anti-tumor performance were studied.The zeolite imidazole framework(ZIF-8)and manganese chloride were used to prepare the reaction precursor,and PSMC was prepared by high-temperature pyrolysis and atom migration,and the material preparation process was explored.Through TEM,SEM,XPS and other test methods,the existence of Mn as a single atom node in PSMC and the unique hollow structure are analyzed.The ability of PSMC to generate active oxygen was explored by detecting the absorbance changes of indicators such as methylene blue,which proved that it can catalyze the generation of active oxygen under acidic conditions.Under the irradiation of 808 nm laser,the PSMC heats up rapidly,and the photothermal conversion efficiency reaches 55%.In vitro tumor cell experiments and in vivo anti-tumor experiments in mice and showed excellent anti-tumor performance,tumor cell growth inhibition rate reached 45%.The successful preparation of PSMC provides a new feasible solution for the realization of chemical dynamic/photothermal combined therapy.In order to further improve the therapeutic effect of the single atom catalyst,a polyethylene glycol modified manganese-doped single atom catalyst supported gold(PSMCA)nanocomposite therapy platform was designed and used to realize the combined treatment mode of chemical kinetic/photothermal/starvation.Based on the unique properties and unique spatial structure of PSMC,the photoreduction method is used to grow gold in situ in its interior and pores.Gold has the properties of glucose oxidase and photothermal agent at the same time.Combining it with a single atom catalyst can achieve multi-mode treatment and effectively enhance the photothermal performance of the material,increasing its photothermal conversion efficiency to 64%.In in vitro tumor therapy and in vivo anti-tumor therapy in mice,PSMCA showed excellent therapeutic ability.The inhibition rate of tumor cells was increase to 61%,which was about16% higher than that of the PSMC system alone,which proved its feasibility as an anti-tumor treatment material.This study is based on manganese doped single atom catalysts loaded with gold to achieve a combination of multiple treatment methods,which provides a new idea for the development of single atom catalysts in the field of tumor therapy.This thesis discusses the synthesis process and material optimization of single atom catalysts.This study is based on manganese-doped single atom catalyst supported gold to realize the combination of various treatment methods.The synthesis process of single atom catalyst and later material modification are discussed.It is proved that the designed composite material can effectively destroy tumor cells,and is a single-atom catalyst.The future development of atomic catalysts provides new ideas.