Analytical Sciences

Abstract − Analytical Sciences, 20(9), 1277 (2004).

Amperometric Hydrogen Peroxide Biosensor Based on Horseradish Peroxidase-labeled Nano-Au Colloids Immobilized on Poly(2,6-pyridinedicarboxylic acid) Layer by Cysteamine
Chun-Xiang LI,* Ke-Qing DENG,** Guo-Li SHEN,** and Ru-Qin YU**
*College of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, P. R. China
**State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
A sensitive hydrogen peroxidase (H2O2) amperometric sensor based on horseradish peroxidase (HRP)-labeled nano-Au colloids has been proposed. Nano-Au colloids were immobilized by the thiol group of cysteamine, which was associated with the carboxyl groups of poly(2,6-pyridinedicarboxylic acid) (PPDA). With the aid of the hydroquinone, the sensor displayed excellent electrocatalytical response to the reduction of H2O2. Compared with the non-Au-colloid modified electrode, i.e., PPDA/HRP, the Au-colloid modified electrode exhibited better performance characteristics, including stability, reproducibility, sensitivity and accuracy. The biosensor shows a linear response to H2O2 in the range of 3.0 × 10-7 - 2 × 10-3 M. The detection limit was 1.0 × 10-7 M.