Development And Application Of A New Bipolar Analysis And Detection Platform Based On High Performance Quantum Dots

Electrochemiluminescence（ECL）is a technology with high detection sensitivity,low operating cost,and wide application range.It has great potential of development in the field of analysis and detection.Currently,the luminescent materials of ECL sensors are mainly ruthenium-based molecules.With the development of materials science,more and more new light emitters exhibit excellent ECL performance.However,some inherent defects,such as hydrophobicity,solvent dependence,and aggregation-induced quenching,greatly limit the use of these materials in ECL sensing applications.Bipolar electrodes（BPE）can solve these problems well.The bipolar system has two separate space,which have the necessary conditions for biomolecule detection and stable ECL generation.Therefore,the study of ECL systems based on bipolar electrode is significant to further broaden the application range of ECL sensing.By studying the properties of the new luminophore and the characteristics of the bipolar electrochemical analysis system,this thesis proposes a BP-ECL analysis and detection platform which is suitable for the detection of a variety of biomolecules while ensuring a stable and efficient ECL response.Many new materials are used in electrochemiluminescence and broaden the scope of their biological analysis and detection.The main work is divided into the following four parts:（1）A tetraphenylethylene derivative aggregates were prepared by a template self-assembly method,and the ECL phenomenon was observed in acetonitrile solution.The ECL strength of the aggregates was nearly 20 times higher than that of the monomer.As a new type of luminophore,the molecule is expected to show broader application prospects in the field of ECL sensing and analysis.（2）CsPbBr₃ QDs were synthesized by a ligand-assisted reprecipitation method,and the ECL of CsPbBr₃ QDs was observed in acetonitrile solution.Through the analysis of the electrochemistry and ECL of CsPbBr₃ QD,a reasonable ECL mechanism was proposed,and the influence of solvent polarity and oxidation potential on the ECL of CsPbBr₃ QD was studied respectively.The result shows that at a lower oxidation potential,CsPbBr₃ QD has a higher quantum yield and good stability in non-polar solvents.（3）A molecularly imprinted sensor was prepared by electropolymerization method and used as the sensing element,the Ru（bpy）₃²⁺/TPr A system was used as the ECL reporting element,and the c-MIP-BPECL platform for the analysis and detection of dopamine is established through the bipolar electrode,which has realized electricity between the sensing electrode and the reporting electrode.The established platform has excellent detection performance in the linear range of 2.0×10^-7-2.6×10^-4 M and 2.6-6.2×10^-4 M,and the limit of detection（LOD）is 1.0×10^-7 M.In addition,this study confirmed that molecular imprinting technology can effectively improve the sensitivity and detection selectivity of the bipolar system,which provides a new research idea for the combination of molecular imprinting and bipolar electrochemiluminescence.（4）By introducing bipolar electrode into electrochemiluminescence,a bipolar electrochemiluminescence detection platform（CBP-ECL）based on a series of new luminophores was established,which can separate the recognition system of target molecules in aqueous media,and generate a stable and high-intensity ECL signal in the organic phase.The established analysis and detection platform was used to detect H₂O₂.The linear range is 2.0×10^-5-1.2×10^-2 M,and the limit of detection（LOD）is 9.2×10^-8M.This study uses the spatially separated structural characteristics of the closed bipolar electrode to construct a new bipolar detection platform,which provides a new solution for the wide application of organic luminescent reagent ECL sensing.In this thesis,by synthesizing and studying the ECL characteristics of new luminescent materials such as tetraphenylethylene derivatives and perovskite quantum dots,and combining molecular imprinting technology,the bipolar electrochemiluminescence platform is innovatively designed for the detection of dopamine.And further using the structural characteristics of the closed bipolar electrode,a bipolar electrochemiluminescence platform that suitable for two-phase is designed,which greatly broadens the application range of ECL reagents.It is great significant for the further development of the new generation of high-sensitivity,high-resolution and high-throughput analysis technology.