Study On Green Synthetic Of Doped Cerium Dioxide Nanoparticles And Their Efficacy

In recent years,the application of cerium dioxide nanoparticles in biology and medicine has gradually emerged in research,so it is necessary to improve the safety and biocompatibility of cerium dioxide nanoparticles.This problem can be solved well by the method of green synthesis.In this project,a better raw material was selected through comparative experiments,and the cerium dioxide nanoparticles synthesized by it were characterized and evaluated for efficacy under the best process conditions.In addition,the synthetic cerium dioxide nanoparticles are doped and modified to improve their efficacy and make better use.The specific contents are as follows:（1）Betaine,tea polyphenols,rutin and carboxymethyl chitosan were used as raw materials to synthesize Ce O₂nanoparticles,and the scavenging rate of DPPH free radicals was used as an indicator by Na OH synthesis,and the optimal raw material was selected as carboxymethyl chitosan.In addition,the synthesis conditions were optimized,and the concentration of cerium nitrate was finally determined to be 0.2 M,the calcination time was 2h,and the calcination temperature was 600°C.（2）The synthesized Ce O₂nanoparticles are cubic fluorite structure,the morphology is spherical,and the particle size is about 17.5 nm.It has good UV absorption,with an SPF value of 38.26 at 10,000μg/m L.At the same time,it has certain antioxidant and anti-inflammatory abilities,which increase with the increase of sample concentration.Within a certain range,Ce O₂nanoparticles are not toxic to Ha Ca T cells,indicating that it has good biocompatibility.In addition,it also has a certain inhibitory effect on bacteria and fungi.（3）The morphology of Ce O₂nanoparticles does not change after silver doping,but its grain size and unit cell volume decrease,and the lattice spacing increases.The doping of silver also redshifted its ultraviolet absorption peak,and the SPF value increased,up to 41.26.The doping of silver also significantly improves the oxidation resistance of Ce O₂nanoparticles.However,its cytotoxicity to Ha Ca T will increase with the increase of doping amount and concentration.In addition,with the increase of silver doping content,the inhibitory rate of Ce O₂nanoparticles on bacteria and fungi is getting higher and higher.However,anti-inflammatory activity is not very related to doping silver.