Preparation,Characterization And Properties Research Of W₁₈O₄₉-xMn Nanomaterials

Cancer treatment methods based on near infrared light(NIR)have been extensively studied by researchers in cancer clinical investigations,such as photothermal therapy(PTT)and photodynamic therapy(PDT).The NIR area(700-1100 nm)is a biologically transparent window.Laser absorption of the tissue irradiated to this area is very low,and the light can reach deep inside the tissue.Since a single treatment method cannot achieve a satisfactory treatment effect,people have done a lot of work in developing the synergistic effect of photothermal therapy and photodynamic therapy based on near-infrared light to optimize the effect of tumor treatment.Compared with a single PTT or PDT,combination therapy can not only avoid a large number of drug injections to reduce side effects,but also greatly improve the therapeutic effect.One of the feasible combined treatment strategies is to design a PTT and PDT synergistic treatment system triggered by a single NIR laser.W₁₈O₄₉ was prepared by solvothermal method using different solvents,and the samples were anayzed using XRD,SEM and other characterization methods.Samples prepared with different solvents have different morphology and crystallinity.The ability of W₁₈O₄₉ dispersions of different concentrations to generate singlet oxygen(¹O₂)was studied and compared.1,3-Diphenylisobenzofuran(DPBF)was used as an indicator of ¹O₂,and ¹O₂ was generated at a concentration of 1 mg/m L better oxygen capacity.At the same time,according to the heating curve,1 mg/m L solution by 808 nm laser irradiation reached the temperature is 42.1 ^oC for 16minutes can kill the tumor.According to the cooling curve,the photothermal conversion efficiency is good and calculated to be 26.21%.W₁₈O₄₉ has good biocompatibility to normal cells and has killing effect on MCF-7 tumor cells.It provides a certain foundation for W₁₈O₄₉ nanomaterials to realize PDT/PTT synergistic treatment.In order to solve the problem that the tumor hypoxia microenvironment limits the effect of PDT,Mn-doped W₁₈O₄₉(W₁₈O₄₉-x Mn,x is the mole percentage of doped manganese)were prepared using different solvents.XRD and SEM characterization showed that Mn²⁺ions can replace the W site of monoclinic W₁₈O₄₉nanorods,it interferes with the formation of W₁₈O₄₉ morphology,but does not change the growth orientation of W₁₈O₄₉.The photothermal conversion efficiency of nanomaterials prepared with ethanol,n-propanol and isopropanol as solvents reached19.6%,33.47%and 33.68%.Ultraviolet visible absorption spectroscopy tests the production of ¹O₂,in which Mn²⁺reacts with H₂O₂ to generate oxygen and increase the content of ¹O₂,showing good photodynamic performance.The nanomaterial prepared with isopropanol as a solvent exhibits a two-phase coexisting nanomaterial and excellent photodynamic performance.In addition,the W₁₈O₄₉-x Mn nanomaterial and human umbilical vein endoderm cells(HUVEC)are co-cultured,showing good biocompatibility.