Preparation Of Chalcogenides And Their Application In Cancer Diagnosis And Treatment

Nanomaterials have special properties that differ from traditional materials,such as quantum size effect,small size effect and surface effect,are widely used in the biological field.Integrating nanomaterials with nanotechnology to solve medical problems has been hot research in the field of nanomedicine.At present,nanomedicine is expected to overcome the problems of traditional medicine and provide new ways for the early diagnosis and treatment of cancer.In this paper,we designed and synthesized two major categories of low-toxicity chalcogenide nanomaterials which were used to construct biosensors with signal amplification technology.The biosensors with high sensitivity and selectivity,excellent stability and reproducibility can achieve early diagnosis of cancer.In addition,the nanomaterial with photothermal conversion property has been used for cancer therapy research.Details are as follows:1.Controllable synthesis of cubic EuSe nanoparticles based on DDT and its application in near-infrared photothermal cancer therapy:Preparate EuSe nanoparticles(NPs)with good dispersion through thermal decomposition method,and explore factors that affect its size,shape and performance.Regulate the amount of n-dodecanethiol(DDT),the ratio of Eu and Se,the temperature and the reaction time to synthesise cubic EuSe NPs.Modified oil-soluble cubic EuSe NPs into water-soluble cubic EuSe NPs using surface modification technique.Experiment with photothermal property of nanomaterials,results showed that cubic EuSe NPs had the performance of photothermal transformation,the photothermal conversion efficiency of cubic EuSe NPs under the laser irradiation of 808 nm was 29%.Further,cubic EuSe NPs were applied for the photothermal therapy of breast cancer cells(MCF-7),Experiments on living-dead cells showed that cubic EuSe NPs could heat up rapidly to kill cancer cells under near infrared light.Therefore,cubic EuSe NPs can be used as a novel potential photothermal conversion nanomaterials for cancer therapy.2.Applications of self-reinforced ECL cytosensors based on CTAB-encapsulated cubic EuSe nanoparticles:The oil-soluble cubic EuSe NPs were transferred to aqueous solutions using the cationic surfactant cetyltrimethylammonium bromide(CTAB),modified EuSe@CTAB using silicon dioxide(SiO2)and 3-aminopropyltriethoxysilane(APTES),and surface functionalization with folic acid(FA)to obtain EuSe@CTAB@SiO2@FA NPs,ECL cytosensor was constructed based on the specific binding capacity of FA and folate receptor(FR)which was over-expressed on the cytomembrane of Hela cells.The presence of CTAB could accelerate the rate of electron transfer in the reaction to enhance ECL signal and improve detection sensitivity.The experimental results showed that the detection range of the cytosensor was I.5×102～3.0±1.07 cells/mL,the detection limit was 23 cells/mL,and it had excellent selectivity and good stability,which realized the sensitive detection of Hela cells,provided one possibility for clinical analysis.3.Synthesis and characterization of CuFeS2 quantum dots and application for ECL immunosensors:CuFeS2 quantum dots(QDs)with uniform size were synthesized by thermal injection,the water-soluble CuFeS2 QDs were obtained by surface modification technique.Assembled CuFeS2 QDs with gold nanoparticles(Au NPs)and magnetic beads(MB)to obtain MB@Au@CuFeS2 QDs,which enhanced the ECL signal of CuFeS2 QDs;then graphene oxide(GO)and Au NPs were electrodeposition on the surface of the electrode(GCE)to improve the conductivity of electrode surface,thus to achieve double amplification of ECL signal.In this paper,sandwich-ECL immunosensor was designed to detect Cyclin-Dl(CCND1)which was overexpressed on breast cancer cells(MCF-7).The experimental results showed that the immunosensor had a wide detection range(40 fg/mL～0.8 mg/mL)and low detection limit(15.8 fg/mL),exhibiting good performance with excellent selectivity,stability and reproducibility.