Direct electron transfer of glucose oxidase immobilized on a mesoporous silica KIT-6 matrix to screen-printed electrodes

• Published in: Journal of nanoscience and nanotechnology Vol. 9; no. 8; p. 4767
• Main Authors: Zuo, Shaohua, Wu, Xianbo, Teng, Yuanjie, Yuan, Huihui, Lan, Minbo, Lawrance, Geoffrey A, Wei, Gang
• Format: Journal Article
• Language: English
• Published: United States 01.08.2009
• Subjects: Adsorption; Electrodes; Electrons; Enzymes, Immobilized - chemistry; Glucose Oxidase - chemistry; Microscopy, Electron, Scanning; Silicon Dioxide - chemistry; X-Ray Diffraction
• ISSN: 1533-4880
• DOI: 10.1166/jnn.2009.1080

The direct electron transfer of glucose oxidase (GOx) immobilized on a large-pore mesoporous silica KIT-6 matrix fixed to a screen-printed electrode (SPE) and its application as a disposable biosensor were studied. KIT-6 plays a vital role in this method through immobilizing GOx and facilitating the electron communication between the active centers of GOx and the surface of the SPE. GOx immobilized on KIT-6 maintains its bioactivity and structure and displays stable and well-defined redox peaks with a formal potential of -428 mV (vs. Saturated Calomel Electrode), with a heterogeneous electron transfer rate constant of 4.15 s(-1) in phosphate buffer (0.05 M, pH 6.0). Upon the addition of glucose into air-saturated phosphate buffer solution, the reduction peak current decreases, which can be used analytically for glucose detection. The biosensor exhibits a linear response to glucose concentration ranging from 0 to 2.83 mM and a sensitivity of 7.29 microA (mM)(-1) cm(-2) at an applied potential of -0.5 V. The present work provides a promising strategy for fabricating a novel and disposable mediator-free glucose biosensor, which could be potentially mass-produced through further development.