Phytic Acid-Based Layer-by-Layer Assembly for Fabrication of Mesoporous Gold Film and Its Biosensor Application

作者：Wang, Yao; Ma, Xiaoling; Wen, Ying; Zheng, Yaqing; Duan, Guoping; Zhang, Zongrang; Yangz, Haifeng^*

来源：Journal of the Electrochemical Society, 2010, 157(1): K5-K9.

DOI：10.1149/1.3246592

• GLASSY-CARBON ELECTRODE
• HORSERADISH-PEROXIDASE
• HYDROGEN-PEROXIDE
• TIO2 PHYTATE
• CYTOCHROME-C
• DIRECT ELECTROCHEMISTRY
• MULTILAYER FILMS
• OXIDE MEMBRANES
• NANOPARTICLES
• IMMOBILIZATION

Phytic acid was introduced as a binder to construct a controllable structure at an electrode surface. In this paper, phytic acid and gold nanoparticles were assembled onto the surface of a gold electrode layer-by-layer to form a three-dimensional mesoporous gold interface. Then, a high sensitive horseradish peroxidase (HRP) biosensor was prepared based on the proposed mesoporous interface. Atomic force microscopy, Raman spectroscopy, and electrochemical impedance spectroscopy were applied to characterize the process of forming nanofilms. Hydrogen peroxide was detected with the aid of a hydroquinone mediator to transfer electrons between the electrode and the HRP. The immobilized HRP displayed the feature of a peroxidase and gave an excellent electrocatalytic response to the reduction of H2O2. The biosensor showed a linear response to H2O2 over a concentration range from 6.5 x 10(-6) to 1.4 x 10(-5) mol L-1 with a detection limit of 3.3 x 10(-6) mol L-1 (signal-to-noise ratio = 3). The Michaelis-Menten constant (K-M(app)) was estimated to be 0.078 mmol L-1. The biosensor exhibited high sensitivity, good accuracy, and acceptable stability.

• 出版日期2010
• 单位上海师范大学