Electrochemistry Research Of Biosensor Based On Nanocomposite Materials

Biosensor possesses some characteristics obtained strong selectivity, high sensitivity, fast chemical response, low cost of preparation and implement detection online in complicated conditions etc, is one of hot research items of disciplines of analysis and detection in every country. Nanocomposite materials applied to electrochemistry domain as a novel biosensing medium material attract extensive interest of many researchers. In this paper, prepared some kinds of nanocomposite materials and dedicated to new biosensor modified by them,primary research contents contained some following aspects:1. Pt nanoparticles were deposited on the Si substrate electrod of gold plated with the methods of potentiostatic deposition, Fe₃O₄ magnetic nanoparticles (MNPs) were preparaed with the method of chemical coprecipitation were immobiled on the surface of modified electrod, then the Au/Pt/Fe₃O₄electrod was preparaed and used for detection of liquid ethanol, the detection of ethanol without enzyme came true; it was found Fe₃O₄ MNPs played strong catalytic role for oxidation of ethanol. The linear range of Au/Pt/Fe₃O₄NPs electrod for ethanol was 2×10-5 1.1×10-4 mol·L^-1 and detection limit was 3.193×10-6 mol·L^-1(S/N = 3).2. Based on electric conductivity and wide potential window of ionic liquid(IL) and electric property of single-wall carbon nanotubes(SWCNTs), composite material of IL–SWCNTs was preparaed, glucose sensor was builded with this material for immobiling glucose oxidase(GOx). It showed good response, sensitivity and stability for long time for glucose detection. Linear range for the detection of glucose was from 0.5×10-6 mol·L^-1 to 12×10-6mol·L^-1 while detection limit was 6.26×10-8 mol·L^-1 (S/N = 3).3. Prussian blue (PB) nanoparticles protected by Polyvinylpyrrolidone (PVP) were preparaed and characterized by TEM and UV-vis. Au/DNA/PVP-PB/MCH electrod was preparaed for detection of H2O2, in which PB nanoparticles were used as sensitive material, its linear range was 6.25×10-7 1×10-5 mol·L^-1and detection limit was 7.12×10-8 mol·L^-1 (S/N = 3). Besides,the H2O2 of Romas celles was detected by it, The linear range was 400 80000 mL^-1. This sensor showed good electrochemistry response and sensitivity to H2O2.