Synthesis And Sonodynamic Anti-tumor Properties Of Co-based Nanomaterials

Given the high death rate from cancer,people have invested a lot of energy in basic and clinical research to explore and develop effective and practical cancer treatment.The development of efficient anti-tumor agents has a high practical significance.The recent remarkable technological progress in the field of nanotechnology provides unprecedented opportunities for nano-drugs to enhance the development of cancer treatment.At present,the main treatment methods of cancer include surgery,natural therapy,radiotherapy and chemotherapy,but these treatment methods have the disadvantages of large toxic side effects,easy recurrence and metastasis,and low cure rate.Innovative therapeutic methods include sonodynamic therapy,photothermal therapy,photodynamic therapy,chemdynamic therapy.These therapeutic methods are non-invasive,controllable,highly selective,excellent therapeutic effect and other advantages.Sonodynamic therapy（SDT）is a novel treatment that induces apoptosis of tumor cells by stimulating the production of cytotoxic reactive oxygen species（ROS）by sonosensitizers under low intensity ultrasound（US）conditions.Sonodynamic therapy has many advantages,including high accuracy,deeper tissue penetration,fewer side effects,targeting,non-invasive,easy regulation and so on.In order to further improve the anti-tumor effect,multiple diagnosis and treatment methods were coordinated and integrated on this basis.Based on this,the Co-based nanomaterials were synthesized in this paper.It was taken as the main research object,and the synergistic integration of sonodynamic therapy and chemodynamic therapy was conducted to study its anti-tumor properties.Specific research contents are as follows:（1）Porous hexagonal nanosheets with defect rich nickel（Ni）doped cobalt oxide（Ni-Co O@PEG）were synthesized by a simple hydrothermal method as sonosensitizer.The Ni-doped band gap is further reduced from 1.67 e V（Co O）to 1.36 e V（Ni-Co O）.ESR analysis showed that the active group was divided into dissolved O₂ and US generated electron ¹O₂.In addition,doping introduces more oxygen vacancy（Ov）,which is not only conducive to the efficient separation of electron holes,but also enhances the interaction with O₂ and promotes the production of ROS.Ni-Co O@PEG nanosheet has POD and CAT simulation activities,which can convert endogenous H₂O₂ into·OH and O₂.The above cascade process induces a large anticancer effect,facilitating subsequent suppression of metastasis and recurrence by invoking anti-tumor immunity.（2）Co–based metal-organic framework material（MOF）was prepared.The nanomaterial can produce ROS under ultrasonic conditions and achieve sonodynamic therapy to inhibit tumor growth.CC11@PEG has catalase activity and peroxidase activity,can catalyze H₂O₂ to produce oxygen and·OH.The O₂ produced can relieve tumor hypoxia,promote the production of more ROS in sonodynamic therapy,and improve the effect of sonodynamic therapy.In addition,the material can consume intracellular glutathione,prevent excessive GSH depletion ROS in the tumor area,and improve the therapeutic effect.The material can also perform MR Imaging,showing good tumor diagnosis and treatment effect.（3）The defect rich cobalt titanate nanomaterials were synthesized.Oxygen vacancy was produced by calcination of cobalt titanate nanomaterial and sodium borohydride under inert gas atmosphere.Compared with the raw material,the prepared cobalt-rich defect titanate material showed high electron hole separation ability and high ROS production ability,and was a good ultrasound sensitive agent.In addition,it shows good biological safety under the condition of no ultrasound.It is suitable for treatment in vivo.