Electropolymerization Of Luminescence Functional Materials Based On Poly (Aniline-luminol) And Its Analytical Applification

In recent years,the electrochemiluminescence（ECL）sensor has the characteristics of easy miniaturization,low cost,good stability,high selectivity and time-saving,and so on,and it has been widely used in the field of clinical diagnosis,public food safety and environmental monitoring.At the same time,as one of the commonly used chemiluminescent reagents,luminol has been used in ECL detection of different markers.Therefore,the ECL biosensor based on luminol has been paid more and more attention by researchers.In this paper,the luminol and aniline were immobilized on the electrode surface by electropolymerization,and the luminescent properties of luminol in the composite were improved by compounding the materials in favor of luminol luminescence.Based on the poly（aniline-luminol）luminescent functionalized nanomaterials,three novel ECL biosensors were constructed for the sensitive detection of cholinergic in milk,lymphocyte activating gene-3（LAG-3）in serum and hydrogen peroxide in mouthwash.The main contents are as following:1.Poly（aniline-luminol-hemin）nanocomposites was prepared on an electrode surface through electropolymerization.And the obtained nanocomposites were further characterized by scanning electron microscopy（SEM）,atomic absorption spectrometry（AAS）,and electrochemiluminescence（ECL）.The results indicated that hemin was successfully electropolymerized into poly（aniline-luminol）nanocomposites and the ECL intensity of poly（aniline-luminol-hemin）nanocomposites was better than that of poly（aniline-luminol）nanocomposites.Based on the obtained composites,an ECL biosensor for the detection of choline was prepared by enzyme-catalyzed reaction of choline oxidase（CHOD）.The enhanced ECL signal of the prepared ECL biosensor was linear with the logarithm of concentration of choline over the range of 1.0×10^-11～1.0×10^-7mol·L^-1with a low detection limit of 1.2×10^-12mol·L^-1.Moreover,the proposed biosensor has been successfully applied to the detection of choline in the milk.2.Aniline and luminol were deposited on the surface of graphite electrode by electrodeposition.Then,a new type of poly（aniline-luminol-Au NPs）luminescent functionalized nano-material was successfully prepared by electrostatic adsorption of Au nanoparticles（Au NPs）and Polyaniline.Then,the SEM,EDS-Mapping,cyclic voltammetry（CV）and ECL were used to characterize the nanocomposites.The results show that the introduction of Au NPs into poly（aniline-luminol）nanocomposites can not only improve the electron transfer ability of the membranes,but also enhance the ECL properties of the membranes.Based on the excellent electrochemiluminescence properties of poly（aniline-luminol-Au NPs）,the electroplated composites were used to construct a new ECL biosensor for detecting LAG-3.The detection of LAG-3 by this ECL biosensor has the characteristics of wide linear range and low detection limit.The linear range and detection limit are1.0×10^-13-1.0×10^-7mol·L^-1and 6.3×10^-14mol·L^-1,respectively.And the proposed immunosensor can be used for sensitive detection of LAG-3 in serum.3.The feasibility of electropolymerization of poly（aniline-luminol-MWCNT）composite film on graphite surface was studied and the nanocomposites was characterized.The results showed that poly（aniline-luminol-MWCNT）composite material was successfully prepared on the electrode surface,and the material had excellent ECL properties.In this chapter,based on the enhanced effect of H₂O₂on the ECL signal of the material,a new ECL biosensor for detecting H₂O₂was constructed.The enhanced ECL signal was linear with the logarithm of H₂O₂concentration over the range of 1.0×10^-11-1.0×10^-6mol·L^-1and the detection limit was 4.3×10^-12mol·L^-1.The biosensor could be used to detect H₂O₂in mouthwashes.