Synthesis Of Copper And Silver Fluorescent Nanoclusters Anndtheir Application In Biomolecular Analysis

Due to its unique optical properties,biocompatibility and catalytic properties,metal fluorescent nanoclusters are widely used in environmental monitoring,biological assay and cell imaging.The fluorescence properties of metal nanoclusters closely depend on synthesis method and template molecules.There are many methods for the synthesis of fluorescent nanoclusters,however,some of them are unstable,complicate and timeconsuming,especially synthesis of copper and silver fluorescent nanoclusters.The drawback of synthesis methods and unstable fluorescent property limit the application of copper and silver nanoclusters.This thesis focuses on the synthesis and application of copper and silver nanoclusters and discusses the improvement of the synthesis methods of copper and silver fluorescent nanoclusters and their potential application prospects.By optimizing the synthesis conditions,copper nanoclusters with novel and stable fluorescence properties were prepared here for ascorbic acid detection.Silver nanoclusters synthesized by improved light reduce methods was used for dopamine detection.The content of this thesis has three parts as follows:1.The synthesis of trypsin-copper nanoclusters was studied and used for the detection of ascorbic acid.The mixing of trypsin and copper ion can produce a trypsincopper complex under alkaline conditions and a kind of fluorescent copper nanoclusters could be produced in the presence of ascorbic acid.The fluorescence intensity of the produced copper nanoclusters has a good linear relationship with the concentration of ascorbic acid added.Based on this phenomenon,a fluorescence spectroscopy method for ascorbic acid detection was established based on trypsin-copper nanoclusters.Ascorbic acid in the range from 0.5 to 30.0 mM can be linearly detected with the detection limit of 16.5 ?M.2.Studied a method for a novel fluorescent copper nanoclusters synthesis using ascorbic acid as a template.A fluorescent copper nanocluster was firstly synthesized using a reported method.And then,by further controlling and optimizing the reaction temperature,the ratio of copper to ascorbic acid and pH value,a blue-color and greencolor emission copper nanoclusters was synthesized respectively.The green-emission copper nanocluster has an excitation wavelength of 376 nm and an emission wavelength of 534 nm,while the blue-emission copper nanocluster has an excitation wavelength of 380 nm and an emission wavelength of 452 nm.The green-emission fluorescent copper nanocluster is a new type of fluorescent copper nanocluster that is more stable than other reported copper nanoclusters.3.A green and rapid method for synthesizing bovine serum albumin-silver nanoclusters was established with a light reduction method using bovine serum albumin as a template.Compared with the traditional synthesis method,UV-light was directly used to reduce silver ions to silver nanoclusters.The fluorescence emission peak of the synthesized silver nanoclusters was located at 550 nm that is different from silver nanoclusters synthesized by a common method.In addition,in the presence of dopamine,the absorption and fluorescence intensity of the nanocluster would increase with the increasing of dopamine selectively.Based on this phenomenon,a highly selective and sensitive method for the detection of dopamine was established in the dopamine concentration range from 5.0 to 100.0 ?M with a detection limit of 1.6121 ?M.