Hydrogen peroxide biosensor based on direct electron transfer of horseradish peroxidase with vapor deposited quantum dots
Hydrogen peroxide biosensor based on direct electron transfer of horseradish peroxidase with vapor deposited quantum dots
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基于气相沉积量子点辣根过氧化物酶直接电子转移的过氧化氢生物传感器
DOI：
10.1016/j.snb.2008.12.040
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发表时间：
2009-04-24
影响因子：
8.4
通讯作者：
Zhao, Yuan-Di
中科院分区：
文献类型：
--
作者：
Wang, Zhan;Xu, Qiao;Zhao, Yuan-Di
辣根过氧化物酶（HRP）和亲脂性量子点（QD）被纳入到玻碳（CC）电极表面以各种方式。结果表明，只有当电极通过气相沉积用量子点修饰时，HRP才能将电子直接转移到CC电极上。响应电流与扫描速率呈线性相关，表明该反应是一个表面控制过程。HRP在电极表面的平均覆盖度为2.29 × 10 ~（-11）mol cm ~（-2），非均相电子转移速率常数k为5.80 ± 0.70 s ~（-1）。吸收光谱和傅里叶变换红外光谱表明，固定在电极上的HRP构象没有明显变化。进一步的研究表明，固定化HRP对H2 O2具有良好的催化活性。该修饰电极可作为H_2O_2的传感器，检测线性范围为5.0 × 10 ~（-6）~ 1.0 × 10 ~（-4）M，检出限为2.84 × 10 ~（-7）M。该传感器具有重现性、稳定性。(C)2008 Elsevier B. V.保留所有权利。
Horseradish peroxidase (HRP) and lipophilic quantum dots (QDs) were incorporated onto the surface of glassy carbon (CC) electrodes in various ways. It was found that HRP transfers electron directly onto the CC electrode only when the electrode was modified with QDs through vapor deposition. The response currents were linearly correlated with scan rate, indicating that the reaction is a surface controlled process. The average coverage of HRP on the electrode surface can be calculated as 2.29 x 10(-11) mol cm(-2), and the heterogeneous electron transfer rate constant k was 5.80 +/- 0.70 s(-1). Absorption spectra and Fourier-transform infrared spectra showed that the conformation of HRP immobilized on the electrode has no obvious change. Further studies indicated that immobilized HRP retains excellent catalytic activity to H2O2. The apparent Michaelis-Menten constant was calculated as 0.152 mM. It was also found that the modified electrode could be used as a sensor for H2O2, and the linear range of detection was 5.0 x 10(-6) to 1.0 X 10(-4) M, with a detection limit of 2.84 x 10(-7) M. The sensor exhibited reproducibility, stability. (C) 2008 Elsevier B.V. All rights reserved.