Spectral-resolved Electrochemiluminescence Immunoassay And Electrochemiluminescence Properties Of Perovskite

Electrochemiluminescence(ECL)analysis is technology has attracted wide attention in the fields of biosensing and imaging.Because it does not require excitation of light sources and the experimental equipment is simple,there is no interference of stray light.The selectivity and sensitivity of the experiment are greatly improved.The construction of ECL sensors and the development of new luminescence materials has been a hot spot in recent years.This paper develops a spectrum-resolved ECL sensing strategy that can achieve the simultaneous detection of two components.In addition,the ECL properties of perovskite nanocrystals are also studied.The main contents are as follows:1.A spectral-resolved immunosensor was developed with CdSe(λmax= 550 nm)and CdTe(λmax= 776 nm)nanocrystals as ECL tags,and with(NH4)2S2O8 as cathodic ECL co-reactant.CdSe and CdTe NCs were labeled with respective probe antibodies of carcinoembryonic antigen and alpha-fetoprotein,respectively,and then immobilized onto the glassy carbon electrode via sandwich-type immunoreactions.With the proposed ECL biosensor,carcinoembryonic antigen and alpha-fetoprotein were simultaneously detected and quantified with an extremely low detection limit of 1 pg/mL for carcinoembryonic antigen and 10 fg/mL for alpha-fetoprotein.This work demonstrated the probability of performing multianalyte assays via a spectral-resolved ECL strategy with improved sensitivity.2.The redox nature and ECL of organometal halide perovskite CH3NH3PbBr3 nanocrystals in aqueous medium were investigated.CH3NH3PbBr3 nanocrystals could be electrochemically reduced to negative charge radicals and oxidized to positive charge radicals,respectively,and the charge transfer between positive and negative radicals could generate ECL.A large redox current is unfavorable for ECL.Charge mobility within CH3NH3PbBr3 nanocrystals has a very important influence on the3.intensity of ECL in a co-reactant route.The ECL spectra of CH3NH3PbBr3 nanocrystals were consistent with their photoluminescence spectra with a maximum emission around 535 nm,and full width at half-maximum around 25 nm.This makes the CH3NH3PbBr3 nanocrystals likely to be a good ECL emitter.4.The ECL properties of organometal halide perovskite CH3NH3PbBr3 nanocrystals in the presence of polymethyl methacrylate and carboxylated carbon nanotubes were studied with TPrA as anodic co-reactant.Polymethyl methacrylate and carboxylated carbon nanotubes did not affect the properties of CH3NH3PbBr3 nanocrystals,and CH3NH3PbBr3 nanocrystals still maintained good fluorescence and ECL properties.Because polymethyl methacrylate is insoluble in water,the contact between water and CH3NH3PbBr3 nanocrystals is avoided,making the CH3NH3PbBr3 nanocrystals stable in the detection time.This provides new idea for the application of CH3NH3PbBr3 nanocrystals in ECL analysis.