Influence of redox molecules on the electronic conductance of single-walled carbon nanotube field-effect transistors: Application to chemical and biological sensing
Influence of redox molecules on the electronic conductance of single-walled carbon nanotube field-effect transistors: Application to chemical and biological sensing
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DOI：
10.1021/ja075131f
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发表时间：
2008-03-26
影响因子：
15
通讯作者：
Fan, Janine
中科院分区：
文献类型：
--
作者：
Boussaad, Salah;Diner, Bruce A.;Fan, Janine
为了开发用于化学和生物传感的敏感纳米级器件，我们使用液体门控技术检查了氧化还原介体存在下基于半导体单壁碳纳米管的场效应晶体管（SWCNT-FET）的电导率。例如，氧化还原对 K3Fe(CN)(6)/K4Fe(CN)(6) 和 K2IrCl6/K3IrCl6 被证明可以部分通过电解质门对溶液静电势的影响来调节 SWCNT-FET 电导，如 Larrimore 等人所述。 (Nano Lett. 2006, 6, 3129-1333) 部分是通过氧化还原介体和纳米管之间的电子转移。在后一种情况下，电子转移速率由氧化还原介体和单壁碳纳米管之间的化学势差以及氧化还原对的氧化和还原形式的浓度决定。此外，这些装置可以通过氧化还原酶对酶底物氧化态变化的敏感性来检测其活性。给出了蓝色铜氧化酶（Trametes versicolor 漆酶）的示例，其中 SWCNT 器件电导的变化率与底物 10-(2-羟乙基)吩恶嗪的氧化率成线性比例，在皮摩尔范围内随漆酶浓度变化超过 2 个数量级。这项工作中描述的行为提供了一种使用 SWCNT 进行化学和生物传感的高度灵敏的方法，该方法不同于先前在该材料的文献中描述的电流、电容和场效应型传感方法。
In an effort to develop sensitive nanoscale devices for chemical and biological sensing, we have examined, using liquid gating, the conductance of semiconducting single-walled carbon nanotube-based field-effect transistors (SWCNT-FETs) in the presence of redox mediators. As examples, redox couples K3Fe(CN)(6)/K4Fe(CN)(6) and K2IrCl6/K3IrCl6 are shown to modulate the SWCNT-FET conductance in part through their influence via the electrolyte gate on the electrostatic potential of the solution, as described by Larrimore et al. (Nano Lett. 2006, 6, 3129-1333) and in part through electron transfer between the redox mediators and the nanotubes. In the latter case, the rate of electron transfer is determined by the difference in chemical potential between the redox mediator and the SWCNTs and by the concentrations of the oxidized and reduced forms of the redox couple. Furthermore, these devices can detect the activity of redox enzymes through their sensitivity to the change in oxidation state of the enzyme substrate. An example is given for the blue copper oxidase, Trametes versicolor laccase, in which the rate of change of the SWCNT device conductance is linearly proportional to the rate of oxidation of the substrate 10-(2-hydroxyethyl)phenoxazine, varied over 2 orders of magnitude by the laccase concentration in the picomolar range. The behavior described in this work provides a highly sensitive means with which to do chemical and biological sensing using SWCNTs that is different from the amperometric, capacitive, and field-effect type sensing methods previously described in the literature for this material.