Prussian Blue Nanomaterials Loaded With Iridium In Enhancement Of Tumor Phototherapy

Tumor is one of the major diseases that seriously threaten human health.At present,the treatment methods often used clinically are mainly surgery,chemotherapy and radiotherapy,and there are problems with large trauma area,large side effects of radiotherapy and chemotherapy,cell resistance and other on.Recently,phototherapy with small,efficient,and low toxic side effects of human trauma has entered people’s vision.Phototherapy includes photothermal therapy（PTT）and photodynamic therapy（PDT）.PTT uses materials with high photothermal conversion efficiency to convert light energy to heat under near-infrared sources,locally killing tumor cells to inhibit tumor growth,PDT uses photosensitizers for locally producing reactive oxygen（ROS）under visible light or near-infrared light.Photothermal therapy tumor has good short-term effect and photodynamic therapy duration is longer.However,a single mode of phototherapy often does not completely eradicate tumors,such as photothermal therapy has problems such as the penetration of near-infrared light sources in the body,and the tedious oxygen nature of most solid tumors will severely limit the efficiency of photodynamic therapy.Developing multi-functional materials to realize PTT and PDT collaborative therapy not only inherits the advantages of low phototherapy toxicity and small side effects,but also makes the two treatment methods learn from each other,which is an effective strategy to improve the curative effect and reduce toxic side effects.According to the needs of PTT and PDT collaborative therapy,Prussian blue with photoheat conversion capability and catalase-like synthesis and iridium nanoparticles with oxidase activity,constructed the Prussian blue nanocomposite（Ir-PB）with iridium nanoparticles on its surface,and characterized its composition,structure,stability,optical properties and in vitro phototherapy effect.The specific research is as follows:Prussian blue nanoparticles loaded with iridium was composed by co-precipitation and we controlled iridium loaded in composite by changing feeding ratio.The morphology and structure was determined by transmission radio mirror,X-ray diffraction,The dispersdispersion and stability of Ir-PB Using UV-visible-near-infrared absorption spectroscopy and fluorescence spectrum,we confirmed that Ir-PB has a strong absorption peak at the first near-infrared window at 808 nm,And has a better light and thermal effect,Meanwhile,a hydroxy radical（·OH）and singlet oxygen（¹O₂）that can destroy the cell mitochondria can be produced by laser irradiation at a wavelength of 808 nm.Using the oxygen analyzer to verify the active and oxygen production effects of Ir-PB solution,we selected Prussian blue nanoparticles with the best effective iridium load,and had better optical and oxygen production properties compared with Prussian blue nanoparticles,to provide the basis for subsequent in vitro cell experiments.To confirm the application of the material at the cell level,CCK8experiments were used to demonstrate good biocompatibility.In vitro phototherapy experiments confirmed that the phototherapy effect of Ir-PB was slightly stronger than Prussian blue,which can kill more than 80%of He La cells under 808 nm,0.8 W/cm²laser irradiation of 10 min,demonstrating the development potential of Ir-PB NPs in the field of tumor phototherapy,and fluorescence experiments confirmed that catalase activity at the cell level,decomposed H₂O₂in the tumor microenvironment,improve the oxygen deficiency state in the tumor system,and enhanced the PDT treatment effect of tumors.In conclusion,the Prussian blue nanometerials loaded with Iridium is a good photothermal agent and photosensitizant with good biocompatibility,which can improve the PDT effect by improving the tumor dull oxygen environment,providing endogenous oxygen,and with good photothermal vitality,and it can be expected as new nanomaterials for PTT/PDT collaborative treatment of tumors.