Spatially Resolved Chemical Detection with a Nanoneedle-Probe-Supported Biological Nanopore
Spatially Resolved Chemical Detection with a Nanoneedle-Probe-Supported Biological Nanopore
复制标题
使用纳米针探针支持的生物纳米孔进行空间分辨化学检测
DOI：
10.1021/acsnano.8b09667
复制
发表时间：
2019
期刊：
影响因子：
17.1
通讯作者：
White Ryan J.
中科院分区：
文献类型：
--
作者：
Shoji Kan;Kawano Ryuji;White Ryan J.
在这篇文章中，我们描述了金纳米针离子通道探针的定量表征，并证明了该探针的实用性，用于空间分辨检测的小分子使用离子通道活性。我们的报告建立在Ide及其同事的最近报告的基础上，他们报告了使用用聚乙二醇单层修饰的蚀刻金线作为脂质双层和随后的单离子通道记录的支持。虽然这种纳米针电极的方法以前报道过，在我们的报告中，我们研究了几个操作参数对离子通道测量和电化学现象的性能的影响，这些现象发生在支持的双层和金电极之间的纳米限制空间。更具体地说，我们解决的支持单层的长度和组成的电解质浴通道电流测量的影响，并提供了一个定量描述的工作电极（双层充电）进行电流。此外，我们证明了自由扩散蛋白质控制蛋白质插入方向（尖端侧）的能力，这是以前没有报道过的，前一种方法（尖端侧）能够使用重建的α-溶血素通道进行β-环糊精（βCD）的单分子检测。最后，预计未来使用的纳米针为基础的生物纳米孔探针在扫描探针显微镜，我们证明了定量和空间分辨的微流体通道中的βCD分子的浓度的能力。我们相信，从长远来看，所描述的基于纳米针的生物纳米孔探针可以用于例如使用离子通道的扫描离子电导显微镜。
In this article, we describe the quantitative characterization of a gold nanoneedle ion channel probe and demonstrate the utility of this probe for spatially resolved detection of a small molecule using ion channel activity. Our report builds on recent reports of Ide and co-workers, who reported the use of an etched gold wire modified with a poly(ethylene) glycol monolayer as a support for a lipid bilayer and subsequent single ion channel recordings. Although this nanoneedle electrode approach was reported previously, in our report, we investigate the effects of several operational parameters on the performance of the ion channel measurement and electrochemical phenomenon that occur in the nanoconfined space between the supported bilayer and the gold electrode. More specifically, we address the effects of length of the supporting monolayer and the composition of the electrolyte baths on channel current measurements and provide a quantitative description of what carries current at the working electrode (double-layer charging). In addition, we demonstrate the ability to control the direction of protein insertion (tip sidevsbath side) with freely diffusing protein, which has not been previously reported, with the former method (tip side) enabling single-molecule detection of β-cyclodextrin (βCD) using a reconstituted α-hemolysin channel. Finally, anticipating future use of a nanoneedle-based biological nanopore probe in a scanned-probe microscopy, we demonstrate the ability to quantify and spatially resolve the concentration of βCD molecules in a microfluidic channel. We believe, in the long term, the described nanoneedle-based biological nanopore probe can be employed in, for example, scanning ion conductance microscopy using ion channels.