The Construction And Pesticides Detection Of The Electrochemical Biosensor Modified By Nickel And Copper Doped Cobalt Oxide

Organophosphorus and carbamate pesticide as the inhibitor of the acetylcholinesterase can reduce the activity of acetylcholinesterase in the human body.Due to the inhibition,the neurotransmitter acetylcholine's decomposition and production are not effectively balanced,thereby affecting the human nervous system and endangering human health.The chromatography,mass spectrometry,and chromatography-mass spectrometry were developed to performed the pesticide residue.In recent years,electrochemical biosensor technology has become a new research hotspot in pesticide residue detection because of its rapid detection and easy operation.In this paper,electrochemical biosensors modified with nanomaterials are based on the inhibition of acetylcholinesterase to achieve rapid and sensitive detection of pesticides.At the same time,the scanning electron microscopy,transmission electron microscopy,X-ray diffraction,X-ray photoelectron spectroscopy was employed to performed the morphology and composition of the carbon based metal oxide hybrid nanomaterials that derived from the synthetic organic metal framework materials,and two electrochemical biosensors were prepared for effectively detecting pesticides:?1?The nickel-doped carbon-supported cobalt oxide prepared by hydrothermal method was dissolved in absolute ethanol,then fixed to the surface of the glassy carbon electrode by drop-coating method,and the acetylcholinesterase was immobilized by chitosan and nafion solution.The electrodes are stored in the refrigerator for later use.Throughing a series of electrochemical tests on the electrochemical workstation,the detection of the pesticide carbofuran was achieved,and a relatively good current response was obtained.Under the optimal test conditions,the linear range of the prepared electrochemical biosensor for carbofuran was 1.9×10^-12 M/L-1.9×10^-66 M/L,and the detection limit reached 1.9×10^-12M/L,for the real sample detection of carbofuran,the relative standard deviation is 3.73%.?2?The copper-doped carbon-based cobalt oxide nanosheets synthesized by hydrothermal method are stacked together.It provides more fixed active sites for acetylcholinesterase.After modification,the biosensor exhibits excellent electrochemical performance.After optimization of experimental conditions,the biosensor showed a good detection performance for chlorpyrifos.It showed a good linear relationship at a pesticide concentration of 2.5×10^-12 M/L-2.5×10^-6 M/L,and its stability and repeatability also meets high requirements...