Electrochemical And Electrogenerated Chemiluminescent Collisions Of Ruthenium (Ⅱ) Tris(2,2’-Bipyridyl)Functionalized Nanoparticles

Electrochemical analysis of single nanoparticle detection technology has been developed in recent 20 years,which mainly involves single nanometer material study of electrochemical properties,electrocatalytic activity,individual material properties,individual biomolecular behavior and so on.Nanoporous electrochemistry,which appeared in the 1950 s,has been realized the detection of single molecule,single nanoparticle,single cell,etc.but this technology is an indirect method,which cannot obtain the electrochemical properties of nanoparticle itself.As a convenient and rapid method,Electrochemical analysis of single nanoparticle not only can obtain the properties of single nanoparticles(SNPs),such as the particle size,concentration,aggregation,and catalytic reactivity;but also has broadened applications in many fields,including electrocatalysis,bioelectrochemistry,and biosensing.At present,the single particle detection methods mainly include the following types:optical methods,scanning probe microscopy method,electrochemical method and so on.Single particle collision electrochemical detection is mainly based on four modes:blocking,integral electrolysis,electrocatalytic amplification and charge substitution.Electrogenerated chemiluminescence(ECL)method have the double advantages of both electrochemical and chemical luminescence method.Compared with electrochemical methods,ECL allows the detection of analytes at low concentrations over a wide linear range.Compared with fluorescence methods,ECL does not involve a light source,spectroscopic system and can simplify the instrument,reduce the background value.However,there are few reports on ECL detection of SNPs collisions.Thus,how to use ECL to detect SNPs collision to further reduce the background signal and improve the detection signal sensitivity is the focus of our research.In this thesis,based on two different single nanoparticle,the electrochemical and ECL collision behaviors of SNPs on ultramicroelectrode(UME)are studied.The fullthesis is divided into three chapters,the main contents are summarized as follows:In chapter 1,firstly,the concept,characteristics,preparation methods and related applications of UME are summarized.Secondly,the characteristics and application of single particle are introduced.Then,the basic principle and research status of single particle electrochemical collision are reviewed.Finally,the content and research significance of this thesis are presented.In chapter 2,the electrochemical and ECL collision behavior of single Au-Nafion@Ru nanoparticles on Au UME are studied.which it based on the surface of Au-Nafion nanoparticles was functionalized with Ru(bpy)3Cl2·6H2O(Ru).The results show that the Au-Nafion@Ru nanocomposite has stronger current compared with Nafion@Ru nanocomposite.The relationship between Au-Nafion@Ru current,charge,collision time and number were obtained from the electrochemical collision current-time curve.In addition,with the presence of the coreactant reagent Tri-n-propylamine(TPr A),the simultaneous signal of Au-Nafion@Ru/TPr A by electrochemical and ECL detection methods are realized.The strategy developed in this study may be a promising approach and could be extended to the developing of electrochemical and ECL collision system for detection of other single particle.In chapter 3,the electrochemical and ECL collision behavior of single Meldola’s Blue(MDB)-Ru nanoparticles on Au UME are studied,which it based on the surface of organic dye-MDB nanoparticles was functionalized with Ru.The electrochemical collision method of new type organic dye nanoparticles was established on the UME.The results show that MDB-Ru nanocomposite has good current response signal in the UME collision.Besides,ECL behavior of MDB-Ru/TPr A and MDB-Ru/N,N-dibutyl ethanolamine(DBAE)are studied on Au UME and gold electrode,respectively.The results show that MDB-Ru/DBAE system has stronger ECL intensity and the ECL intensity was approximately 10 times at gold electrode.In this work,the electrochemical collision system of organic dye single particle isextended and a new idea for the detection of electrochemiluminescent single nanoparticles is provided.