Modified electrode based on immobilizing horseradish peroxidase on nano-gold with choline covalently modified glassy carbon electrode as base

作者：Zheng Yu; Lin Xiang Qin^*

来源：Chinese Journal of Analytical Chemistry, 2008, 36(5): 604-608.

DOI：10.1016/S1872-2040(08)60034-1

• choline
• nano-gold
• horseradish peroxidase
• modified electrode

Glassy carbon electrode was covalently modified with choline, which can improve the activity of the electrode markedly. The choline film on the modified electrode with plenty of positive charges could adsorb nano-gold colloids with negative charges, the nano-gold colloids could immobilize horseradish peroxidase (HRP) to form a hydrogen peroxide (H(2) O(2)) sensor. The electrochemical characteristics of the biosensor were studied by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). As the result showed, the biosensor was with good catalytic activity. The surface coverage of HRP (Gamma*) was 1.2 x 10(-9) mol/cm(2), the K(M)(app) of HRP at the biosensor was determined to be (1.55 +/- 0.11) mmol/L. The linear response of the modified electrode to H(2)O(2) was in the range of 1.2 x 10(-6) - 3.2 x 10(-3) mol/L with a detection limit of 4.0 x 10(-7) mol/L. The modified electrode was easy for preparation and exhibited good selectivity and stability.

• 出版日期2008-5
• 单位中国科学技术大学