Electron Transfer Mediated by Surface-Tethered Redox Groups in Nanofluidic Devices.
Electron Transfer Mediated by Surface-Tethered Redox Groups in Nanofluidic Devices.
复制标题
DOI：
10.1002/smll.201603268
复制
发表时间：
2017-02
期刊：
影响因子：
13.3
通讯作者：
T. Steentjes;S. Sarkar;P. Jonkheijm;S. Lemay;J. Huskens
中科院分区：
文献类型：
--
作者：
T. Steentjes;S. Sarkar;P. Jonkheijm;S. Lemay;J. Huskens
电化学提供了一个强大的传感器转导和放大机制，非常适合用于集成，大规模并行分析。本研究展示了柔性线性聚乙二醇聚合物的循环伏安检测方法，该聚合物已被氧化还原活性二茂铁（Fc）基团功能化，并在由两个微尺度电极组成的纳米流体装置内表面系固，该装置以<100 nm的间隙分开。表面结合的聚合物链在水电解质中的扩散允许氧化还原基团重复地将电子从一个电极转移到另一个电极，从而产生大大放大的稳态电流。聚合物长度的变化提供了对电流的控制，因为每个Fc片段的活性似乎取决于相对电极的聚合物层可以相互渗透从而交换电子的程度。这些结果概述了传感装置的设计规则，这些设计规则是基于通过将分析物结合到聚合物链上来改变聚合物的长度、灵活性和/或扩散性。这种纳米流体的配置提供了一种放大和高灵敏度的替代其他电化学检测机制。
Electrochemistry provides a powerful sensor transduction and amplification mechanism that is highly suited for use in integrated, massively parallelized assays. Here, the cyclic voltammetric detection of flexible, linear poly(ethylene glycol) polymers is demonstrated, which have been functionalized with redox-active ferrocene (Fc) moieties and surface-tethered inside a nanofluidic device consisting of two microscale electrodes separated by a gap of <100 nm. Diffusion of the surface-bound polymer chains in the aqueous electrolyte allows the redox groups to repeatedly shuttle electrons from one electrode to the other, resulting in a greatly amplified steady-state electrical current. Variation of the polymer length provides control over the current, as the activity per Fc moiety appears to depend on the extent to which the polymer layers of the opposing electrodes can interpenetrate each other and thus exchange electrons. These results outline the design rules for sensing devices that are based on changing the polymer length, flexibility, and/or diffusivity by binding an analyte to the polymer chain. Such a nanofluidic enabled configuration provides an amplified and highly sensitive alternative to other electrochemical detection mechanisms.