| Electrochemiluminescence(ECL),as a branch of electrochemistry,is a product of the combination of electrochemistry and chemiluminescence technology.It has the advantages of simplicity,efficiency,and sensitivity,widely used in environmental testing,clinical diagnosis,and food testing.After the luminescent material or identification element is fixed on the surface of the electrode,a certain voltage is applied to it to cause the system to undergo redox reaction to obtain the ECL signal.In the process of ECL research,we found that it is necessary to improve the sensitivity and stability of the sensor.Therefore,the introduction of nanomaterials can be used as a co-reaction promoter to improve the sensitivity of detection,nanomaterials with larger specific surface area and abundant active sites can effectively improve the stability of the sensor.This article mainly starts from the development of nanomaterials with better biocompatibility and excellent ECL performance,and constructs a new type of ECL sensor for sensitive drug detection.The specific research work is divided into the following parts:1.Fe2O3/Au NPs/GCE detection of permethrinIn this chapter,an ECL sensor has been developed for the determination of permethrin based on Fe2O3 and Au NPs.Au NPs were prepared by reducing chloroauric acid with ascorbic acid.Fe(NO3)3·9H2O and PVP as the core layer,PVA as the shell layer,using the coaxial electrospinning method,nanofibers with a core-shell structure were prepared,after drying and high-temperature calcination,Fe2O3 nanomaterials are obtained.The Au NPs and Fe2O3 were assembled on the electrode using the drip coating method to construct an ECL sensor with better sensitivity and stability.Among them,Au NPs show higher electron transfer efficiency due to small specific surface area and good electrical conductivity.Fe2O3adsorbs more electrochemically active substances due to its loose structure,and at the same time can be used as a co-reaction promoter to improve the sensitivity of the sensor.Permethrin can enhance the ECL response of the entire system,and this feature provides the possibility for sensor preparation.In addition,as the concentration of permethrin increases,the ECL response increases,and the content of permethrin can be determined by the change in ECL intensity.Under the best experimental conditions,the ECL sensor can effectively detect permethrin in the range of 2.6×10-9 mol/L to 4.3×10-5 mol/L,the detection limit is 8.7×10-10 mol/L.It provides a simple and reliable method for the determination of permethrin,and has broad application prospects in pesticide detection.2.MIP/Nafion/Fe2O3@Ru(bpy)32+/GCE detection of clenbuterolBased on Nafion/Fe2O3@Ru(bpy)32+,CLB as template molecule and pyrrole as functional monomer,an ECL sensor was prepared using molecular imprinting technology to achieve selective detection of CLB.Fe2O3 as a carrier due to its loose structure,combined with Nafion membrane to achieve immobilization of Ru(bpy)32+on the electrode surface.According to the combination of different concentrations of CLB and CLB holes on the surface of molecularly imprinted membranes,different intensities of ECL signals will be generated,and a new method for detecting CLB has been constructed.The logarithm of the concentration of CLB and the ECL response has a good linear relationship.The linear range was from 1×10-9 mol/L to 1×10-4mol/L with a detection limit of 3.3×10-10 mol/L.In addition,the experimental conditions have been optimized,the selectivity and repeatability of molecular imprinting were investigated,and it performed well in actual sample detection.3.Nafion/Ach E/GO@MWNTs/Ru(bpy)32+/Zn O-Fe2O3/GCE detection of organicphosphorusThis chapter constructs an ECL biosensor based on Nafion/Ach E/GO@MWNTs/Ru(bpy)32+/Zn O-Fe2O3/GCE for the detection of organophosphorus.Use the mixture of PVP,Fe(NO3)3·9H2O ang C4H6O4Zn·2H2O as the core layer and PVA as the shell layer,Zn O-Fe2O3 nanomaterials were prepared by coaxial electrospinning and high-temperature calcination.Zn O-Fe2O3,Ru(bpy)32+,GO@MWNTs,Acetylcholinesterase(Ach E),Nafion were fixed to the surface of glassy carbon electrode by layer and layer.The synthesized Zn O-Fe2O3 and GO@MWNTs were selected as supporting material to anchor Ru(bpy)32+and Ach E,respectively.Meanwhile,Zn O-Fe2O3can be used as co-reaction accelerators,improve the ECL intensity.The porous structure and abundant active groups of GO@MWNTs interact with enzymes to improve the stability of the sensor.When the concentration of OPs increases,enzyme activity is inhibited,resulting in a decrease in ACh produced by ATCl;in addition,OPs will consume the co-reactant and reduce the concentration of the co-reactant,ECL response is weakened.The novel ECL sensor achieved an efficient detection of OPs range from 6.6×10-10 mol/L to 3×10-6mol/L with a detection limit of 2.2×10-12 mol/L.The strategy can provide a simple and reliable approach for determining of OPs,indicating that it has great application prospects in malathion detection. |
PDF Full Text Request