A New Method For The Determination Of Fenitrothion And Butachlor In Environmental Samples Based On Electrochemical Sensors

In recent years,with the increasing population and deepening industrialization,environmental pollution has became increasingly serious and has gradually became one of the most challenging issues in the world.In order to better detect trace pollutants in the environment,it is necessary to establish a fast,sensitive and cost-effective detection method.Electrochemical sensors have received widespread attention due to their advantages of simple assembly,portability,high sensitivity,selectivity and stability.In this paper,the subjects of study were fenitrothion and butachlor.Electrochemical sensors were prepared based on metal nanomaterials for the detection of fenitrothion and molecular imprinting for the detection of butachlor.The main research work is as follows:（1）NiFe₂O₄nanomaterials were synthesized by hydrothermal method,their morphology and structure were characterized by Fourier transform infrared spectroscopy（FTIR）,scanning electron microscopy（SEM）and X-ray photoelectron spectroscopy（XPS）.The NiFe₂O₄/Nafion/GCE electrode was prepared by dispersing NiFe₂O₄nanomaterials in Nafion solution and coating mixture dropwise on the surface of the glassy carbon electrode.After air drying,the NiFe₂O₄/Nafion/GCE electrode was prepared.The properties of the electrode were characterized by cyclic voltammetry（CV）and alternating impedance spectroscopy（EIS）,the feasibility of detecting fenitrothion was studied.According to the study of scanning rate,the basic principle of the electrode for detecting fenitrothion was explained.Explored the effects of material loading and electrolyte p H on the detection performance of the electrode.Under the optimal conditions,the current response intensity of CV method is linearly related to the concentration of fenitrothion,shows a low detection limit(1×10^-8mol·L^-1),wider detection range(3×10^-7-1.018×10^-3mol·L^-1),excellent anti-interference performance,stability for long-term detection and repeatability.The method was applied to the determination of fenitrothion in actual samples,the recovery rate was102.41%-104.13%.（2）By utilizing the affinity between pyrrole and butachlor,a MIP/PPy/GCE electrode for rapid and ultra sensitive detection of butachlor was prepared by simultaneously polymerizing pyrrole and butachlor on the surface of the GCE through electrodeposition.The NIP/PPy/GCE electrode was prepared using the same method without the addition of butachlor.The electrochemical characterization of the two electrodes was studied based on CV method,differential pulse voltammetry（DPV）and EIS method,the basic principle of the MIP/PPy/GCE electrode for detecting butachlor was explained.Explored the effects of electrochemical elution and incubation time on the detection performance of MIP/PPy/GCE electrodes.Under optimal conditions,the current response intensity of the DPV method exhibits a"4S"logistic logarithmic relationship with the concentration of butachlor,exhibits a good detection range(0.3-1600 pmol·L^-1),extremely low detection limit(0.16 pmol·L^-1),excellent selectivity and repeatability.This method has been applied to the determination of butachlor in actual samples,the recovery rate was 98.4%-102%.Figure[22]table[8]reference[91]...