Ferrocene was immobilized on the surfaces of single-walled carbon nanotube (SWCNT) bundles, and the ferrocene/SWCNT hybrid shows a high stability not only in water but also in an organic solvent. Furthermore, the nanohybrid exhibits greatly improved electron-transfer behavior and provides more electrochemical active sites. This study presents an alternative route to reconstitute an electrical contact through a single-walled carbon nanotube-ferrocene hybrid between the active center of glucose oxidase and the electrode. The fabricated glucose biosensor shows a fast rate and a high sensitivity. (C) 2008 Elsevier B.V. All rights reserved.