MWNTs Modified Glassy Carbon Biosensor for Glucose

Significant research and development efforts have been devoted to producing reliable glucose sensors for in vitro or in vivo applications, because of high demand for blood glucose monitoring and other application. The outstanding electrochemical properties of carbon nanotubes, along with their high surface area, can promote electron-transfer and enlarge enzyme loading, which provide the available ground for their application in biochemical sensors. We have successfully constructed a glucose oxidase supported on MWNTs modified glassy carbon (GOD/MWNTs/GQ biosensor. The MWNTs modified glassy carbon electrode was referred as MWNTs/GC electrode. The characterization results of cyclic voltammetry and chronoamperometry for the prepared MWNTs/GC electrode and the GOD/MWNTs/GC biosensor show that MWNTs can enormously enhance the electron transfer. The reaction process is a surface-controlled one and a reversible, two-proton coupled with two-electron redox reaction process. The linear range of the biosensor response to glucose reaches 2 mmol/L with the sensitivity of 0.61 muA/mM and the responding time less than 2 s. The biosensor prepared by this method has a rather long stability after storage in PBS for two weeks with the response to glucose almost no change