Preparation Of Chemiluminescent Probe Of Biomimetic Antibody On Fe₃O₄ Particle Surface And Its Detection For 2,4-D

2,4-dichlorophenoxyacetic acid（2,4-D）has been widely used as herbicide because it can be used as plant growth regulator in low concentration and herbicide in high concentration.The remain of 2,4-D has a significant influence on public body through crop enrichment or direct contact.hence,it is important to expand a speed and susceptible method to monitor 2,4-D.At present,the instrument detection method of human urine and water body has been able to achieve a lower detection concentration.However,the sample pretreatment and instrument cleaning process are complex and tedious,as well as labor-intensive and and costly.In this paper,the enzyme-linked immunochemiluminescence（ELISA）analysis method was combined with the magnetic molecular imprinting technology to detect 2,4-D residual,this method has the detection broad and sensitivity of enzyme-linked immunochemiluminescence assy,at the same time,it has the specific selective recognition ability of molecular imprinting,and can be easily recycled under the effect of external magnetic field,which overcomes the lack of selectivity of traditional enzyme-linked immunochemiluminescence.In the first chapter,the preparation,development and application of molecularly imprinted biomimetic antibody and enzyme-linked immunochemiluminescence were introduced.The second chapter is the preparation and result characterization of Fe₃O₄nanoparticles.The Pros and cons of three ways to prepare magnetic Fe₃O₄ are talk over.The ending show that the experimental scheme（1）results in a relatively uniform particle size.Further orthogonal experiments are carried out to optimize the experimental scheme,and further characterization is carried out by grain diameter spread,X-ray fluorescence diffraction,infrared,Raman,etc.The outcome are demonstrated in the external,The grain diameter of Fe₃O₄ prepared by experiment（1）is about 250nm,the particle size distribution is uniform,and there are almost no other peaks in the XRD spectrum,which shows that the prepared Fe₃O₄ is relatively pure.Further more,the strongest peak（311）calculated by Scherrer formula shows that the microspheres are composed of Fe₃O₄ nanoparticles with the grain size of 9.01nm.The infrared spectrum analysis shows that the surface of Fe₃O₄ nanoparticles is rich in hydroxyl groups.The magnetic bionic antibody are prepared in Chapter 3 to Chapter 5 respectively Fe₃O₄@SiO₂,Fe₃O₄@AM,Fe₃O₄@4-VP bionic antibody was testify by scanning electron microscopy,IR,Raman and kinetic thermodynamics.The ending.make known that the three kinds of imprinted shells were successfully prepared.In the kinetic and thermodynamic experiments,the largest Adsorption capacity of Fe₃O₄@SiO₂imprinting material is 36.9mg·g-1,non imprinting Fe₃O₄@SiO₂ is 13.0mg·g-1,The maximum adsorption capacity of imprinted material Fe₃O₄@AM is 45.7 mg·g-1,non imprinted material Fe₃O₄@AM is 17.6 mg·g-1,The maximum adsorption capacity of imprinted material Fe₃O₄@4-VP can reached 63.2mg·g-1,however the non imprinted Fe₃O₄@4-VP is only 23.3 mg·g-1.In Chapter 6,we introduced a direct competitive enzyme-linked immunochemiluminescence method for the detection of 2,4-D,and select the magnetism with excellent adsorption capacity prepared in Chapter 5 Fe₃O₄@4-VP As a bionic antibody,at the same time,the optimal distribution ratio of each group of chemiluminescent intensity was obtained through optimization tests which included p H,luninol,H₂O₂ and others.Because of the molecular imprinted bionic antibody pair 2,4-D has specific adsorption capacity.Therefore,a certain amount of 2,4-D is added to96 well plate with molecularly imprinted bionic antibody to compete with enzyme-linked 2,4-D（2,4-D-HRP）for direct reaction.Then,the chemiluminescent substrate solution is added to measure the luminescent intensity,and the standard curve of the experiment is fitted with a typical four parameter equation,Finally,the detection line of the selective chemiluminescence method for 2,4-D can reach 1.33 x 10^-8mg/L.The chapter 7 is the conclusion and the expectation.