The Study Of Potential Electrochemical Biosensor Based On The Copper Electrode

In this thesis, the potentiometric electrochemical sensors of sulfite and glucosewere designed, built up and studied based on different chemical modifications ofcopper electrodes.According to the coordination effect of8-hydroxyquinoline with copper atom,the self assembly membrane was formed on the surface of copper electrode surface.The SAM modified copper electrode shows a recognition properties to sulfite anion intwo concentration ranges of1.0×10^-17mol/L～1.0×10^-11mol/L and1.0×10^-10mol/L～1.0×10^-6mol/L with the lowest detection limit of1.0×10^-17mol/L. The recognitionmolecular mechanism has been verified by semi-empirical quantum chemicalcalculation with MOPAC2009.The in-site modification of copper electrode surface of secretions induced fromphotosynthetic bacteria with substrate, sulfite, was prepared, and used as a biosensorto determine sulfite by potentiometry in aqueous solution in the concentration rangesof1.0×10^-16mol/L～1.0×10^-10mol/L,1.0×10^-9mol/L～1.0×10^-6mol/L with thelowest detection limit of1.0×10^-16mol/L. The Sulfide ion-induction process has beenverified by fluorescence spectrometry. The method has been used in the detection ofsulfite in river of Shenyang normal university campus with the recovery of93.52%～97.28%and RSD of4.09%.The in-site modification of copper electrode surface of secretions induced fromphotosynthetic bacteria with substrate, glucose, was prepared, and used as a biosensorto determine glucose by potentiometry in aqueous solution in the concentration rangeof1.0×10^-7mol/L～1.0×10^-3mol/L with the lowest detection limit of1.0×10^-7mol/L,which meet the demand of glucose detection in blood. The method has been used inthe detection of glucose in human blood with the recovery of93.24%～102.6%andRSD of5.59%.In summary, these studies focus on the SAM of8-hydroxyquinoline on copperelectrode surface to obtain the sulfite anion potentiometric sensor, and the in-site modification of copper electrode surface of secretions induced from photosyntheticbacteria with substrates to obtain the sulfite and glucose biosensors, which shows anexample to use the cheap metal electrode and offers an idea and method to design thenew biosensors.