Preparation Of Noble Metal Nanoclusters And Their Applications In Biological Detection

As more and more diseases endanger human health,the early diagnosis of the disease is crucial to the discovery and control of the disease.The detection of specific biomarkers of the disease can greatly improve the survival rate of patients.Therefore,the demand for the development of fast,sensitive and cost-effective biosensors has greatly increased.Metal nanoclusters(NCs),due to their special size-dependent chemical,electrical and optical properties,have been widely used in basic scientific research and a variety of biological applications.In this paper,two different fluorescent metal nanoclusters are synthesized.In order to improve the anti-interference ability and accuracy of the detection platform,other materials with fluorescent properties are introduced.The constructed ratio fluorescence sensing platform has the function of self-correction to the signal,Which greatly reduces the system error.Based on the above principles,different ratio fluorescence sensing platforms were constructed and applied to the specific quantitative detection of acetylcholinesterase.In the chapter 2,we first demonstrated the intrinsic oxidase-like activity of the synthesized single-atom nanozymes,and combined it with the fluorescent properties of the synthesized polyvinylpyrrolidone-stabilized copper nanoclusters to form a specific The ratio fluorescent probe for the detection of acetylcholinesterase is linearly related to the concentration of acetylcholinesterase in the range of 2-70 U L^-1 based on the ratio of two easily distinguishable fluorescence emission intensities at the same excitation wavelength,and the detection limit is 0.56 U L^-1.Successfully complete the applicability experiment in actual samples.In addition,the relevant mechanism of the fluorescence interaction between the two materials was discussed,which opened the way for the application of single-atom nanozymes in the field of fluorescence analysis.In the chapter 3,firstly,blue fluorescent silicon nanoparticles with good water solubility were prepared by hydrothermal synthesis,and then silver ion-modified orange fluorescent gold nanoclusters were prepared,and the self-assembly method of electrostatic interaction The combination of the two forms a new type of fluorescent nanocomposite material.Based on the principle that the product obtained by acetylcholinesterase-catalyzed hydrolysis of the substrate has a sulfhydryl group to quench the fluorescence of the gold nanoclusters,a new ratio fluorescence sensing platform was constructed,and the detection range was 0.03-4.0 U L^-1.The quantitative detection limit of acetylcholinesterase is as low as 0.019 U L^-1.And it has been verified that its application in actual biological samples has potential value.