Design And Synthesis Of New Inorganic Composite Nanomaterials And Their Applications In The Field Of Biomedicine

The rise of nano-materials in medical field can effectively avoid the disadvantages of traditional cancer treatment methods to a certain extent.Inorganic nano-materials have a series of unique physical and chemical properties,and have unique potential application value in the field of biomedical imaging and cancer treatment.Prussian blue is a kind of dyestuff.It has attracted much attention in biomedical field because of its high photothermal conversion,low biological toxicity,facile and environmental synthesis,and strong controllability of structure.Bismuth sulfide,as a transition metal sulfur compound,has the characteristics of low toxicity and high photothermal conversion efficiency.Bismuth sulfide and Prussian blue nanoparticles were selected as photothermal conversion agents,and their properties and applications in the field of cancer diagnosis and treatment were investigated.The results are as follows:1.A new two-dimensional sheet bismuth sulfide nanostructure was successfully synthesized by solvothermal method using triphenyl bismuth and dibenzyl disulfide as raw materials.The surface of the material was modified by PEG.The modified composite was characterized by different methods.The experimental results show that the material has large surface area,surface negative electron enrichment,high drug loading capacity,good pH drug release performance and light intensity.Bi₂S₃-PEG has high thermal performance and good photoacoustic imaging effect with low cytotoxicity.DOX@Bi₂S₃-PEG has a significant lethal effect on cancer cells under near infrared irradiation at 808 nm.The combination of photothermal therapy and drug treatment has been realized.2.We synthesized a Prussian blue nano-sized particle with uniform particle size by hydrothermal method.The carboxylated chitosan hydrogel with pH-responsibility was coated onto Prussian blue nanoparticles by emulsion polymerization.Through the modification of the nanoparticle structure,hollow structure were prepared by thermal decomposition of its hollow mesoporous structure to produce drug free azo two isopropyl imidazoline hydrochloride.（AIBI）,the mesoporous structure was encapsulated by gelatin with enzymatic hydrolysis.The obtained composite structure has been characterized by various methods.It has been proved that the material has good water solubility,low biological toxicity,good near infrared absorption capacity and high photothermal conversion capacity.The innovation of this subject is the photothermal performance of Prussian blue,which not only realizes the pyrolysis of AIBI,but also provides the heat source of photothermal therapy.