辣根过氧化物酶在Au-Gemini纳米复合物修饰玻碳电极上的直接电化学

将辣根过氧化物酶(HRP)固定在Au-Gemini纳米复合物修饰的玻碳(GC)电极表面,制备了HRP修饰电极(HRP/Au-Gemini/GC),研究了HRP在Au-Gemini纳米复合膜中的直接电化学,考察了其对H_2O_2的电催化还原作用.研究表明,HRP在Au-Gemini纳米复合膜中发生了准可逆的电化学反应,其氧化峰峰电位(E_(pa))和还原峰峰电位(E_(pc))分别为-0.236 V和-0.273 V.HRP/Au-Gemini/GC修饰电极对H_2O_2具有良好的电催化还原响应,其表观米氏常数K_m=2.0×10~(-5)mol/L,H_2O_2浓度在1.0～7.0μmol/L范围内与催化电流呈线性关系.该研究为实现氧化还原酶的直接电子传递和生物传感器的构制提供了一种有效途径.

Direct Electrochemistry of Horseradish Peroxidase Based on Au-Gemini Nanocomposite Modified Glassy Carbon Electrode

A horseradish peroxidase (HRP) modified electrode (HRP/Au-Gemini/GC) was fabricated by immobilized on the Au-Gemini nanocomposite modified glassy carbon (GC) electrode. The direct electrochemistry of HRP was investigated on the HRP/Au-Gemini/GC electrode, and the modified electrode was applied to study the electrocatalytic reduction of H_2O_2. The results showed that the direct electrochemistry of HRP can be facilely achieved on HRP/Au-Gemini/GC and a couple of quasi-reversible redox peaks of HRP were observed at about -0. 236 V(E_(pa)) and -0. 273 V(E_(pc)). The HRP/Au-Gemini/GC electrode displayed good electrocatalytic reduction of hydrogen peroxide. The apparent MichaelisMenton (K_m) was2.0×10~(-5) mol/L and the linear range was 1.0-7.0 μmol/L. The study provides an efficient strategy to achieve the direct electron transfer of redox enzymes and fabrication of biosensors.