Fabrication And Application Of Enzymatic Biosensors Based On Nano-gold Particles & Functional Multi-walled Carbon Nanotubes

Biosensor plays an important role in clinical and environmental test. It is very important to choose the modification materials with excellent properties to build a biosensor with high selectivity and high sensitivity. Carbon nanotubes(CNTs) are becoming more and more valuable because carbon nanotubes have the excellent physical, chemical, mechanical, electrical properties. Carbon nanotubes can be used as modification materials in biosensors. It can increase the electron transfer efficiency and reduce the electro-active material’s working potential. And it has good biocompatibility and other excellent characteristics. Based on these backgrounds, by using carbon nanotubes and other modification materials, a novel biosensor was manufactured in this thesis.In this thesis, the multi-walled carbon nanotubes were treated in acid to be functionalized. After modified the functional multi-walled carbon nanotubes(F-MWCNTs) on the surface of the electrodes, nano-Au particles(AuNPs) and neutral red(NR) were electro-deposited on the electrode by the cyclic voltammetry method. At last, the modified electrode could adsorb horseradish peroxidase(HRP) on the surface of glassy carbon electrode(GCE). Finally, HRP/AuNPs/PNR/F-MWCNTs/GCE electrochemical biosensor was prepared. This novel biosensor has good catalytic performance to hydrogen peroxide(H2O2). The stability and sensitivity of this biosensor are also good.In the construction of the enzymatic biosensor experiments, we researched the modification methods and optimized the modification conditions. The horseradish peroxidase biosensor is easy to build and shows good performance for the detection of H2O2, but its sensitivity and stability need to do further study.