Shape-controlled Synthesis Of Metal Oxide/multi-walled Carbon Nanotube Compositises And Their Application In Electrochemical Glucose Biosensors

Nanomaterials have been widely used to construct the electrochemical glucose biosensors due to their large specific surface area,good biocompatibility,high catalytic efficiency and strong adsorption ability.The synergistic effect of different components in nanocomposites can further enhance the detection performance of biosensor.This thesis put emphasis upon studies on preparation of new carbon nanotubes composites by combining the advantages of metal oxide,poly(3,4-ethylenedioxythiophene)(PEDOT)and carbon nanotubes,which is applied in the construction of electrochemical glucose sensor.The preparation and analysis conditions were optimized,and the properties of as-prepared sensors were investigated systematically for glucose detection.The main original results are as follows:(1)The PEDOT functionalized multi-walled carbon nanotubes(MWCNTs)supporting six-pointed star Cu2O microcrystal composite was synthesized using the string method,and a novel electrochemical glucose sensor was fabricated by modifying this composite on the glassy carbon electrode(GCE).The surface morphology and structure of the synthesized materials were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).Cyclic voltammetry and chronoamperometry methods were used to evaluate the response performance of the prepared sensor toward glucose detection.The results demonstrate that the fabricated Cu2O/PEDOT/MWCNTs/GCE sensor has good electrocatalytic activity to glucose oxidation.Under the optimum conditions,the sensor exhibits a wide linear range from 0.495 ?M?0.374 mM and 0.374 mM?3.446 mM and a low detection limit of 0.04 ?M(S/N=3),as well as excellent reproducibility(seven parallel determination,relative standard deviation is 4.6%),stability(the amperomertic response can still maintain 82.9%of its initial response current after 28 days)and anti-interference ability(L-arginine,H2O2,ascorbic acid,Uric acid,dopamine and sodium chloride have no obvious interference to the glucose detenction).(2)The MWCNTs supporting polyhedron-like CuOx micropartical was synthesized using the anti-solvent method,and a novel electrochemical glucose sensor was fabricated by modifying this composite on the glassy carbon electrode(GCE).The surface morphology and structure of the synthesized materials were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).Cyclic voltammetry and chronoamperometry methods were used to evaluate the response performance of the prepared sensor toward glucose detection.The results demonstrate that the fabricated CuOx/MWCNTs/GCE sensor has good electrocatalytic activity to glucose oxidation.Under the optimum conditions,the sensor exhibits a wide linear range from 2?M?13.21 mM and a low detection limit of 0.75 ?M(S/N=3),as well as excellent reproducibility(seven parallel determination,relative standard deviation is 3.9%),stability(the amperomertic response can still maintain 81.2%of its initial response current after 31 days)and anti-interference ability(L-arginine,H2O2,ascorbic acid,Uric acid,dopamine,epinephrine and sodium chloride have no obvious interference to the glucose detenction).(3)The MWCNTs supporting spindle-like MnOx micropartical was synthesized using the hydrothermal method,and a novel electrochemical glucose sensor was fabricated by modifying this composite on the glassy carbon electrode(GCE).The surface morphology and structure of the synthesized materials were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).Cyclic voltammetry and chronoamperometry methods were used to evaluate the response performance of the prepared sensor toward glucose detection.The results demonstrate that the fabricated MnOx/MWCNTs/GCE sensor has good electrocatalytic activity to glucose oxidation.Under the optimum conditions,the sensor exhibits a wide linear range from 1.37?M?9.834 mM and a low detection limit of 0.6 ?M(S/N=3),as well as excellent reproducibility(eight parallel determination,relative standard deviation is 3.6%),stability(the amperomertic response can still maintain 81.1%of its initial response current after 29 days)and anti-interference ability(L-arginine,H2O2,ascorbic acid,Uric acid,dopamine,epinephrine and sodium chloride have no obvious interference to the glucose detenction).