Preparation And Photothermal Properties Of Tungsten Oxide Nanocomposites

Photothermal therapy is a new method that uses near-infrared laser to irradiate the tumor site,and then the thermal effect of the photothermal conversion agent generates high temperature to kill cancer cells.The advantages of photothermal therapy are small trauma,high selectivity,high treatment efficiency,and small toxic and side effects.It is an effective cancer treatment method.Spherical WO_3-x@PEG were prepared by solvothermal method using PEG-400as surface modifier.By infrared spectrum analysis,PEG was coated on the surface of WO_3-x.The specific surface area of WO_3-x@PEG nanoparticles an reach 125.065m²/g.Under dark conditions,the decolorization rate of the two samples to a concentration of 30 mg/L methylene blue solution was more than 98%within 15 min.The WO_3-x@PEG-Gd nanocomposites was synthesized by solvothermal method using gadolinium nitrate hexahydrate as the source.Control the W:Gd value and the type of surface modifier to obtain nanospheres,nanowires and irregular nanoparticles.Elemental distribution tests showed that the Gd element was enriched in WO_3-x@PEG-Gd nanomaterials.The photothermal performance test showed that when the aqueous solution of WO_3-x@PEG-Gd at a concentration of 1 mg/m L was irradiated with the 808 nm laser with a power of 0.85 W/cm² for 3 min,the solution temperature was above 50oC.WO_3-x@PEG-Gd aqueous solution exhibits excellent CT imaging ability at a concentration of 100 mg/m L.After co-culture of WO_3-x@PEG-Gd and LO2 cells for 24 h,the cell survival rate was above 90%.WO_3-x@DTPA-Gd nanoparticles were synthesized by solvothermal-mechanical stirring method.Elemental distribution test showed that Gd was attached to the surface of WO_3-x@PEG-Gd nanoparticle.In the photothermal performance test,the sample solution was irradiated with an 808 nm laser for 10 min and the temperature reached 46.9oC.The WO_3-x@PEG-Gd aqueous solution at a concentration of 100mg/m L also has excellent CT imaging capabilities.After co-culture of WO_3-x@DTPA-Gd and LO2 cells for 24 h,the cell survival rate was above 89%.In summary,we have synthesized WO_3-x@PEG,WO_3-x@PEG-Gd and WO_3-x@DTPA-Gd,and performed characterization and performance analysis.Analysis shows that tungsten oxide-based nanocomposites are a potential photothermological diagnosis and treatment integrated cancer therapeutic agent.