Development of amperometric glucose biosensor based on glucose oxidase co-immobilized with multi-walled carbon nanotubes at low potential

The electrodes modified with multi-walled carbon nanotube (MWCNT) film containing adsorbed glucose oxidase (GOx) with respect to highly sensitive glucose detection are developed and demonstrated by electrochemical studies at low potential. Glucose-sensing properties were studied using cyclic voltammetric and chronoamperometric techniques. A linear calibration plot was obtained in the concentration range between 1.0 and 500.0 mu M, and the detection limit was determined to be 1.3 +/- 0.1 mu M. Interferences from other biological compounds were studied. The long-term stability, reproducibility, and sensitivity of the GOx biosensor were measured. The proposed glucose biosensor was successfully applied to human serum sample. (C) 2008 Elsevier B.V. All rights reserved.