Institute of Analytical Science/Shaanxi Province Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi'an, China.
Analyst. 2011 Feb 21;136(4):781-6. doi: 10.1039/c0an00379d. Epub 2010 Dec 13.
A novel H(2)O(2) sensor based on enzymatically induced deposition of electroactive polyaniline (PANI) at a horseradish peroxide (HRP)/aligned single-wall carbon nanotubes (SWCNTs) modified Au electrode is fabricated, and its electrochemical behaviors are investigated. Electrochemical impedance spectroscopy of the sensor confirmed the formation of PANI on SWCNTs through the HRP catalytic reaction. Cyclic voltammograms of PANI/HRP/SWCNTs modified Au electrodes showed a pair of well-defined redox peaks of PANI with reduction peak potentials of 0.211 and oxidation peak potentials of 0.293 V in 0.1 M HOAc-NaOAc (pH 4.3) solution. The oxidation peak current response of PANI is linearly related to H(2)O(2) concentration from 2.5 μM to 50.0 μM with a correlation coefficient of 0.9923 and a sensitivity of 200 μA mM(-1). The detection limit is determined to be 0.9 μM with a signal-to-noise ratio of 3. Thus, the synergistic performance of the enzyme, the highly efficient polymerization of PANI, and the templated deposition of SWCNTs provided an extensive platform for the design of novel electrochemical biosensors.
基于辣根过氧化物酶（HRP）/定向单壁碳纳米管（SWCNTs）修饰金电极上酶诱导的电活性聚苯胺（PANI）沉积，制备了一种新型 H（2）O（2）传感器，并研究了其电化学行为。传感器的电化学阻抗谱证实了通过 HRP 催化反应在 SWCNTs 上形成了 PANI。PANI/HRP/SWCNTs 修饰金电极的循环伏安图显示，在 0.1 M HOAc-NaOAc（pH 4.3）溶液中，PANI 具有一对定义良好的氧化还原峰，还原峰电位为 0.211 V，氧化峰电位为 0.293 V。PANI 的氧化峰电流响应与 H（2）O（2）浓度在 2.5 μM 至 50.0 μM 范围内呈线性关系，相关系数为 0.9923，灵敏度为 200 μA mM（-1）。检测限确定为 0.9 μM，信噪比为 3。因此，酶的协同性能、PANI 的高效聚合以及 SWCNTs 的模板沉积为设计新型电化学生物传感器提供了广泛的平台。
