The Preparation Of Metal-organic Framework Materials And NiS Nano-materials And Their Application In Electrochemical Sensor

The metal-organic framework materials(MOFs)have porous structure,adjustable pore and particle size,large specific surface area,easy to modify and other characteristics,which have been favored by more and more researcher.In this paper,the metal-organic framework MIL-101 was synthesized and used to prepare a electrochemical sensor for the rapid detection of morphine.However,MOFs are limited in their electrochemical applications because of their weak electrical conductivity and their insulating properties.In this paper,metal nanoparticles are loaded on the metal-organic framework materials,which can enhance the conductivity and biocompatibility and strong catalytic performance.In this thesis,Au NPs/MIL-101 and Pt NPs@ UiO-66-NH2 were synthesized to construct immunosensor which for detection of microcystins(MC-LR)and C-reactive protein(CRP).In addition,Au NPs/nickel sulfide(NiS)nanoparticles were used as substrates for immunosensor detection of CRP.The details are summarized as follows:(1)In this paper,MIL-101,a kind of metal organic frameworks(MOFs),was synthesized using hydro-thermal method and modified onto the surface of glassy carbon electrode to prepare electrochemical sensor(MIL-101/GCE)to detect morphine quickly and sensitively.The electrochemical behavior of morphine on the sensor(MIL-101/GCE)was characterized by differential pulse voltammetry and cyclic voltammetry.Under the optimized conditions,linear range was from 1.5×10-6to 2.0×10-4 mol/L.The detection limit was 5×10-7 mol/L.The recovery was 101.7%,which is satisfied.The good testing results indicate that the MIL-101/GCE sensor has a great prospect in practical application.(2)This study developed an electrochemical immunosensor for ultrasensitive detection of microcystins-LR in water.MIL-101,a porous metal organic frameworks(MOFs)material based on trivalent chromium skeleton were synthesized by hydrothermal synthesis method and loaded with the Au nanoparticles(Au NPs)to prepare Au NPs/MIL-101 composite materials which were used as a marker to labelanti MC-LR.The composite materials have strong catalytic properties to the oxidation of ascorbic acid.Anti-MC-LR was immobilized on glassy carbon electrode surface using electrodeposition graphene oxide(rGO)as a immobilized matrix to construct a competitive microcystin-LR immunosensor.The electrochemical immunosensor display linear relationship in the range of 0.05 ng/mL-75?g/mL,linear correlation coefficient was 0.9951 and detection limit of 0.02 ng/mL(S/N=3).This sensor was used to detect microcystins-LR in the water sample.The recovery was102.43%,which is satisfied.The good testing results indicate that sensor has a great prospect in practical application.(3)UiO-66-NH2,a kind of metal organic frameworks(MOFs),was prepared by hydrothermal synthesis and loaded with Pt nanoparticles(Pt NPs)to obtain Pt NPs@UiO-66-NH2 nanocomposite material.The material has good catalytic effect on p-nitrophenol.A label-free immunosensor was prepared by immobilizing CRP antibody on glassy carbon electrode with Pt NPs@ UiO-66-NH2.When CRP binds with CRP antibody,the immune complexes formed will obstruct the catalysis of Pt@UIO-66-NH2 to p-nitrophenol and reduce the response current,which can be used to realize the rapid detection of CRP.The detection limit was 0.02 ng/m L,and the linear range was 0.01 to 500 ng/m L.The sensor has the advantages of simple manufacture,low cost,high sensitivity and high stability.(4)In this article,nickel sulfide(Ni S)was synthesized and used to load gold nanoparticles(Au NPS)and modified on the surface of glassy carbon electrode(GCE)by chitosan as immobilized matrix to fix anti-CRP.Ferroennecarboxylic acid was labeled on the C-reactive protein antibody to fabricate sandwich type of C-reaction protein immunosensor.Differential pulse voltammetry(DPV)was used to detect a characteristic peak of ferrocenecarboxylic acid at 0.3V which is propotinal to the concentration of CRP antigen binding with anti-CRP.It may realize the detection of CRP.Under the optimal experimental conditions,the linear range was 0.01-500ng/mL with detection limit of 3.3pg/mL.This immunosensor offers a method for detecting CRP more effectively and more sensitively.