Synthesis And Cancer Theranostic Exploration Of Several Chalcogenide And Rare Earth Nanomaterials

The incidence and mortality of cancer are increasing year by year,bringing a heavy burden to countless families.As nanomaterials have incomparable advantages,nanomaterials have brought dawn for accurate diagnosis and treatment of cancer.In this dissertation,a series of work have been carried out on how to design and synthesize multifunctional nanotheranostics agents,and we investigated their feasibility in the applications of biomedical imaging and cancer diagnosis and treatment.The research content mainly includes the following five parts:1.PEGylated GdF3:Fe nanoparticles(abbreviated as PEG-GdF3:Fe NPs)were reasonable designed and synthesized by hydrothermal/solvent method.PEG-GdF3:Fe NPs has good hydrophilicity,low cytotoxicity and high biocompatibility.At the same dose,PEG-GdF3:Fe NPs can simultaneously enhance the signals of T1/T2 dual-mode weighted magnetic resonance(MR)and X-ray computed tomography(CT)imaging.Therefore,PEG-GdF3:Fe NPs could be used as potential multimodal contrast agents for cancer diagnosis.2.PVP modified copper doped Ag2S nanoparticles(Cu-Ag2S/PVP NPs)were reasonable designed and synthesized by cation exchange and ligand exchange methods.Cu-Ag2S/PVP NPs can be used as photoacoustic(PA)imaging guided photothermal therapy(PTT)nanotheranostics agents.In addition,Cu-Ag2S/PVP NPs with high photothermal conversion efficiency(5 8.2%),low cytotoxicity,rapid excretion in vitro,low long-term toxicity in vivo.More importantly,Cu-Ag2S/PVP NPs can effectively inhibit tumor growth.In vivo experiments indicated that Cu-Ag2S/PVP NPs can be used as multifunctional nanotheranostics agents for cancer diagnosis and treatment.3.Biodegradable CuS nanoparticles(CuS NPs)were reasonable designed and synthesized by organic phase synthesis and ligand exchange method.CuS NPs are promising nanotheranostic platform for in situ magnetic resonance imaging(MRI)guided synergistic photothermal therapy(PTT)and photodynamic therapy(PDT).Based on density functional theory,electrons are easy to transition on(1 0 2)crystal plane under the near infrared light laser radiation,thus CuS NPs have high photo-thermal conversion efficiency(46%).Under 808-nm laser irradiation,then a large amount of Cu+ ions can be released from CuS NPs.Cu+ ions can generate reactive oxygen species in tumor microenvironment.Meanwhile,the oxidation product Cu2+ ions can be applied for in situ T1-weighted magnetic resonance imaging.Therefore,CuS NPs with good biodegradability and biocompatibility have great potentials in cancer diagnosis and treatment.4.Folic acid and bovine serum albumin modified Bi-Bi2S3 nanotheranostic agent(Bi-Bi2S3/BSA&FA NPs)were reasonable designed and synthesized by albumin mineralization method.Bi-Bb2S3/BSA&FA NPs could be used for CT and photoacoustic imaging(PA)guided photothermal therapy(PTT).Bi-Bi2S3/BSA&FA NPs have low cytotoxicity,good biocompatibility and safety,high targeting and excellent ability to inhibit tumor growth.In vivo and in vitro experiments show that Bi-Bi2S3/BSA&FA NPs could be used as potential targeting nanotheranostic agent for cancer diagnosis and treatment.5.Gd-integrated Te nanoparticles(Te@BSA-Gd NPs,named as TBG NPs)were reasonable designed and synthesized by albumin mineralization method.TBG NPs can be used as all-in-one nanotheranostic agents for magnetic resonance(MR)imaging and X-ray computed tomography(CT)imaging guided synergistic photothermal therapy(PTT)and photodynamic therapy(PDT)of cancer.Based on density functional theory,transition of excited electron can be easily occurred from valence band to conduction band on(1 0 1)and(1 0 2)crystal planes of TBG NPs.Therefore,TBG NPs could generate effective photothermal conversion efficiency(NIR-I:42%,NIR-II:41%)and good photodynamic properties on the(1 0 1)and(1 02)crystal planes triggerred by 808-nm(NIR-I)or 1064-nm(NIR-II)laser.More importantly,the biocompatible TBG NPs have several advantages,including excellent safety,good biocompatibility as well as low systemic adverse effects.Based on the above experimental results,TBG NPs have great potentials in cooperative photothermal therapy(PTT)and photodynamic therapy(PDT)guided by multi-modal imaging.