Multiple Signal Amplification Electrochemiluminescence Immunoassay For Detecting Small Molecules Based On Quantum Dots And Gold Nanoparticles

Electrochemiluminescence immunoassay?ECLIA?is a detection method that combines electrochemiluminescence?ECL?with immunoassay?IA?.The use of new functional nanomaterials in electrochemical luminescence immunoassay can lead to a wider detection range,lower detection limits and higher sensitivity,and has a good application prospect.In this paper,nano-materials such as CdSe QDs,gold nanoparticles?AuNPs?,CdSe@CdS and polyethyleneimine?PEI?modified graphene?PEI-GO?were synthesized and used in electrochemical luminescence immunoassay.A representative?-adrenergic agonist—ractopamine?RAC?in pork and pig food and diclofenac sodium?DCF?in sewage samples were detected rapidly and sensitively.This paper mainly includes the following four aspects:1.It elaborates the research background and significance of the paper.This paper mainly introduces ECL,the types of ECL,ECL immunoassay and the application of functional nanomaterials in ECL immunoassay and sensor.2.L-cysteine modified CdSe QDs and gold nanoparticles-labeled horseradish peroxidase have been prepared.The above-mentioned functional nanomaterials were assembled into dual-signal amplified electroluminescent immunosensors for the detection of RAC with a detection limit of 1.7 pg mL^-1.Dual signal amplification technology was based on AuNPs and enzyme cycle amplification.In this immunoassay assay,the presence of AuNPs increases the amount of antibody and HRP,which directly accelerates electron transfer and greatly enhances electrochemical quenching.3.It introduces the preparation and process of CdSe@CdS,AuNPs,PEI-GO,PEI-GO-AuNPs and PEI-GO-AuNPs/CdSe@CdS nanocomposites.These materials wereusedtoconstructmulti-signalamplifiedelectrochemicalluminescent immunosensor for detecting DCF with the minimum detection limit of 1.5 pg mL^-1.Both PEI-GO and AuNPs have a large specific surface area and are capable of supporting a large number of CdSe@CdS-DCF antibodies that are specifically bound by coating antigen to achieve signal amplification.4.The CdSe QDs,AuNPs,CdSe@CdS and GO were characterized by TEM,UV and dynamic particle size distribution.