Nano-CuO And Activated Carbon For Chemokinetic-photothermal Combined Tumor Therapy

Cancer is one of the diseases that pose a significant threat to human health.The use of selective tumor treatment is an effective strategy to reduce side effects and improve treatment effects.It has become the focus of current research,which utilizes the inherent biochemical properties of tumor cells through chemical reactions that can only occur under the specific conditions and the non-toxic substances are converted into highly toxic substances to achieve the purpose of tumor treatment.The content of hydrogen peroxide(H₂O₂)in tumor cells is much higher than that in normal cells,about0.1 m M to 1 m M.Chemodynamic therapy(CDT)is to catalyze the highly concentrated H₂O₂ in tumor cells to produce potent oxidative hydroxyl radicals(^·OH),therefore oxidatively damages tumor cells.Because the content of H₂O₂ in normal cells is much lower than that in tumor cells,CDT has little effect on normal cells.Based on this,CDT realizes selective treatment of tumors.Besides,cancer cells are more sensitive to temperature than normal cells.When the outside temperature reaches 45?,it can damage cancer cells without affecting normal cells.Therefore,photothermal therapy(PTT)using photothermal agents at the tumor site can also achieve selective tumor treatment.Besides,PTT can increase the tumor site's temperature while also promoting the production efficiency of^·OH during the CDT process,enhancing the effect of CDT.This thesis carries out CDT and PTT-CDT combined anti-tumor research.The main research contents and results are as follows:1.Synthesis of two-dimensional CuO nanosheets and its CDT anti-tumor activityFe-based Fenton reagent's CDT process has the disadvantages of low reaction rate in vivo and strict requirements on pH environment.Therefore,it is a feasible strategy to search for alternatives to the low-pH-dependent Fe-Fenton reagents to improve the therapeutic effect of CDT.At the same time,using Cu⁺as a CDT drug is easily converted into Cu²⁺and Cu through redox reactions in the body,thereby reducing the therapeutic effect.On the contrary,Cu²⁺can stabilize in the body while also exerting the CDT therapeutic effect.In this chapter,H₂O₂ is used to treat hollow Cu S(HCu S)to synthesize two-dimensional CuO nanosheets(CuO NSs)for the first time,the Cu²⁺-based CDT process significantly improves the CDT treatment effect.2.Coconut shell-based nano-activated carbon photothermal-chemical kinetics collaborative diagnosis and treatment system construction and activity studyCarbon materials have good biocompatibility and certain catalytic activity,and the development of new types of carbon nanomaterials with high quality,low price,high activity with peroxidase-mimic nanozyme is a promising method.This chapter uses nano activated carbon(ANs)prepared from coconut shell,which has good peroxidase activity.Based on this,the clinically used nuclear magnetic resonance contrast agent gadodiamide was put into ANs holes and wrapped with polyvinylpyrrolidone(PVP)to obtain Gd@PANs.Gd@PANs can effectively catalyze a large amount of H₂O₂ in tumor cells to produce^·OH for cancer treatment,but it has little effect on normal cells.Simultaneously,the photothermal conversion efficiency of PANs is 45.20%,which reflects the excellent PTT function.Furthermore,during the PTT process,the increasing temperature significantly enhanced the peroxidase activity of PANs,achieving the ideal PTT-CDT synergistic therapeutic effect.Gd@PANs can also be used for T1-magnetic resonance imaging(MRI)of tumors to realize the integration of treatment and diagnosis.