Name: development of a 3d graphene electrode dielectrophoretic device
Uploaded: 2014-06-22T14:00:00.000+00:00
Duration: 11 min 15 s
Description: Watch this Scientific Journal Video about Development of a 3D Graphene Electrode Dielectrophoretic Device at JoVE.com

感谢XG科学的慷慨捐赠的石墨烯纸。由于三弗里德里希博士慷慨地让我们用微钻设备。特别感谢扩展到Tayloria亚当斯为叙述的视频。

1，制作出层叠电极/绝缘三维结构<ol><li>为6的石墨烯层，5层胶带设备，切石墨烯纸用手术刀或类似刀片和直边尺到60.7厘米×1.5cm的矩形，并用剪刀切开双面压敏胶粘带为51.3厘米X〜5厘米条纹。 注:由于如图1a所示，这会产生一个3接地电极，3个交流信号电极装置。该7毫米导电层宽度足够窄，以适应到载玻片上，但足够宽，以便于钻孔。 2毫米的长度不容易在重复使用时破裂并有足够的空间来安装铜线。该设备深度由立铣刀深度的限制。 </li><li>打好的石墨烯纸的第一层上干净的载玻片上。慢慢地覆盖石墨烯纸用的胶带1条的一端，使1〜2 mm的边界，以保证两个相邻的石墨烯纸的层间绝缘（ 图1b </strong&gt;）。 </li><li>放置的石墨烯纸在第二层上的带的顶端偏移到的石墨烯纸（ 图1a）的第一层。另外每个导电层后申请中等压力（按均匀拇指，〜100不大于0.7 平方厘米面积），以确保层间良好的密封。 </li><li>重复步骤1.2和1.3的剩余层，留下的顶部和底部层的石墨烯纸。沿图1b所示，从设备的边缘留下一个小约1 mm的边界，以保证纸张的石墨烯层之间的密封绝缘除去过量的磁带上的虚线切割（ 图1b）。 注:双面胶带不利用作为顶层和底层，以避免收集碎屑作为该层叠结构是钻，装在载玻片上，并且填充有样品。 </li><li>用万用表（电阻模式）执行快速绝缘测试。定位的正和负的探针在th的两个不同侧面E设备（A和B上图1c）;高抗（千至兆欧）表示层之间良好的绝缘性。从载玻片移除层状结构为微钻井作准备。 注:设备通常失败的绝缘测试时，在步骤1.2至1.4邻近的石墨烯纸层进行接触。丢弃此类设备。 </li></ol> 2，钻微孔的复合结构<ol><li>使用计算机控制的机械微型铣床和选择端铣刀具有700微米，直径切2.1毫米的长度。固定上使用适当的夹具的微研磨阶段的层状结构（ 图2a和b）。运行铣床的主轴在8600转，然后放下端铣刀慢慢进入并穿过所述叠层结构的中心。移动旋转端铣刀上下贯通的微孔以平滑的内壁。 <ol><li>选择微孔直径，这是由切割宽高比可用端铣刀直径/长度的限制。确保在微孔的内表面是通过微以及垂直和清洁尽可能最佳的电场梯度和光通道。 </li></ol></li><li>从微孔干净的碎片与压缩空气。如1.5中所述，执行另一个绝缘测试。 </li></ol> 3，附加电气导致叠层结构<ol><li>折两个3厘米长的32G铜线成直角在2厘米。混〜1.5 A部分和环氧导电银乙毫升。 注意: <img alt="式（1）" fo:content-width="3in" src="/files/ftp_upload/51696/51696eq1.jpg" /></li><li>手动应用混合银环氧树脂的顶部和所有的3个石墨烯纸层的前端，以保证层上的叠层结构（ 图1c）的A面之间的良好接触，然后将1厘米铜导线端部中的环氧基和任意两个之间层。轻声平方米ueeze层以去除多余的环氧树脂，并保证良好的电接触。重复的层叠结构的B侧。 </li><li>将整个装置在炉架，干通宵70℃，1个大气压。 </li></ol> 4，准备样品和媒体<ol><li>制备电导率的频谱使用电导率仪，290毫甘露醇原液和等渗磷酸盐缓冲盐水（PBS）串行加法等渗介质。 注意:〜290毫渗透摩尔浓度/ L PBS电导率和体积浓度之间存在线性相关性（导通）在〜290毫渗透摩尔浓度/ L甘露醇溶液（不导通）。视频功能的0.01 S / m的导电介质。 </li><li>混合聚苯乙烯珠与准备电导率介质或电子纯净水（〜5×10 -6 S / M），以1:50体积:体积比。这个协议是很容易适应生物的细胞。 </li></ol> 5，安装和试验设备操作<ol><li>夹紧装置ØNTO使用改性纸夹具或等效中等压力（ 图2d）的载玻片上。基脚应该是足够接近的微孔密封层叠结构在载玻片防止样品泄露。夹紧应该适合于显微镜载物台与压力优化，以a）阻止叠层结构的变形，以及b）保证微井流体不泄漏。变形改变了很好的几何形状和光通路减少实验的重复性。 </li><li>使用微注射器或等效慢慢〜1微升的样品注入到微井和避免引入任何气泡。如有必要，重复注射并要当心不要与锋利的针损坏微孔壁上。稍过量填充微孔，并立即滑动​​玻璃盖在微孔去除多余的液体，防止蒸发，并确保可重复的量为每次实验。 注:钻石尖玻璃刀工程以及SCORe和裂纹玻璃盖大小。 </li><li>确保完成层压微型的显微镜载物台，并连接函数发生器的电极导线的两个铜导线在设备上。在的AxioVision（蔡司软件），点击按钮开始摄像机录制的多维采集模式。开始CCD摄像机记录文件具有和不施加的电场的响应后，启动函数产生的信号在一个固定的时间段。 注:在这里，100 Hz至10 MHz的频率，具有15 V 峰峰值信号被应用和实验观察到在10倍的放大倍率在1〜200的载玻片表面之上，持续2秒，而不需要现场和〜5分钟与现场应用。图像进行数字化保存在每秒（fps）的1至5个帧进行进一步分析。 </li><li>当实验完成后，删除该设备，拆除夹具。双方沉浸在肥皂水载玻片和设备，然后冲洗干净。约30时再利用设备s的一贯表现。 </li></ol> 6，数据分析和图像处理<ol><li>分析与优选的软件，如ImageJ的图像数据。从连续的图像在一个给定的时间步长之间的​​质点位移计算速度。 </li><li>计算基于速度编译趋势及理论29比较实验介电泳力和磁场强度。 </li><li>测量粒子的速度沿径向在微井几何与电场梯度的形状相一致。从微井边缘向中心，找出8同心等电轮廓（350，300，... 50，0微米），这导致在7个区域。 注:时间为粒子穿越50微米的距离来计算速度。当几何变化必要吧，等电轮廓进行了小幅调整。 </li></ol>

作者没有冲突披露。

这个手稿详细介绍用于制造新型的6石墨烯层和5层带微型协议。此外，设备的操作是通过6.08微米的聚苯乙烯珠观测到的DEP行为以及一个独特的，几何有关粒子速度分析方法说明。这种多用途的方法构造非线性电动设备比电极与流体层的微细加工技术成本更低，同时产生同样可靠的结果。 此外，这种新颖的三维石墨烯纸微型产生了同意这两个理论预测行为的实验介电泳结果和?...

石墨烯是以其高品质的电子特性和潜在的化学和生物传感器的应用1一种新型材料。石墨纳米片已用于催化剂载体2，3，4的生物传感器，超级电容器5，及复合电极，包括石墨烯/聚苯胺和硅纳米颗粒/石墨复合材料6-8。此手稿描述作为一个独特的三维（3D）的电极，分层微流体装置利用石墨烯纸。石墨烯纸电极层叠绝缘性的双面胶带，并钻出一个室，在该进行的聚苯乙烯珠三维AC介电电泳。 介电电泳（DEP）是指可极化粒子的运动下的非均匀电场。当颗粒都或多或少极化比周围介质，RESU正DEP（pDEP）或负的DEP（NDEP）发生，lting向着最强或最弱的电场运动分别。这种非线性的电动工具已被用于分离，分选，陷印，和识别粒子和生物细胞9-15中。经历的一个偏振粒子的介电电泳力是电场梯度，粒子半径和形状，粒子的介电性能，包括电导率和介电常数，以及介质电导率和介电常数的函数。在传统的两维（2D）DEP，粒子运动是在典型的微加工表面的电极之间形成的电场梯度的主平面;相比，在面内方向中的大多数设备在垂直方向上的运动可忽略不计。但是，利用的电场梯度为三维DEP此第三维允许更高的样品通量并增加了通用性，设计新的和改进的介电电泳分离，其中流动是特拉沃注册结构工程师的磁场梯度16，17。其他具体的设计包括三维绝缘体为基础的DEP 18，三维碳电极的DEP 13，19，和3D电镀DEP 10。就证明了研成三维结构，这种装置可以以连续流模式进行操作，以实现更高的吞吐量。在3D粒子的运动在我们的三维分层观测设备实现频率和介质电导率通过光学显微镜在不同焦距的高度的函数。 Fatoyinbo 等人首先报道了DEP在3D使用交替叠放30μm的铝箔和150微米的环氧树脂膜20层叠电极/绝缘结构。夜蛾等。然后设计类似于3D层叠电极与35μm铜胶带和118微米的聚酰亚胺胶粘剂21。这部作品借用了3D井设计22，23以及唯一地利用为50μm的石墨烯纸的方便作为导电层和100μm的双面胶带作为绝缘层，其中实现密封和足够的电屏蔽。石墨烯纸的多功能性是三维电极微型器件具有明显的优势，因为石墨烯纳米片必须兼任生物传感器，其中该组先前表明24的能力。 石墨烯纸/聚合物内取得的磁场梯度层叠三维微器件依赖于微井的尺寸，石墨烯纸层，和所施加的电场。关键尺寸包括垂直电极间距（导电和绝缘层厚度）和微孔的直径和高度（通过层层叠确定）。该电信号可以通过振幅和频率进行调谐。当前设备的结构是间歇操作，但是可以根据一个连续流动的装置。该设备厂这里描述rication技术适用于开发3D层叠电极与各种各样的石墨烯纳米薄片属性简单地通过交换所使用的石墨烯纸。利用石墨烯纸的优点是通用性的物理和化学性能，降低了费用，并且石墨烯纳米片可以同时作为生物传感器来检测范围广bioanalytes 24。高吞吐量的3D DEP系统的长期目标是，以迅速确定细胞类型25-27，或实现无标记，电介导的细胞病变细胞分选从健康细胞28的人口。本文演示材料的优化和设备的准备和操作，后跟说明和典型结果分析。

<table><tbody><tr><td>Polystyrene Beads</td><td>Spherotech, Inc.</td><td>PP-60-10</td><td>6.08 &amp;mu;m diameter</td></tr><tr><td>Graphene paper</td><td>XG Sciences, Inc.</td><td>XG Leaf B-072</td><td></td></tr><tr><td>Double sided tape</td><td>3M</td><td>N/A</td><td>136 office tape</td></tr><tr><td>Silver conductive epoxy</td><td>MG chemicals</td><td>8331-14G</td><td>Part A &amp;amp; B included</td></tr><tr><td>Mannitol</td><td>Sigma Aldrich</td><td>091M0020V</td><td></td></tr><tr><td>Phosphate buffer saline</td><td>OmniPur</td><td>0381C490</td><td></td></tr><tr><td>Microscope (CCD Camera)</td><td>Zeiss</td><td>Axiovert 200M</td><td></td></tr><tr><td>Function/waveform generator</td><td>Agilent</td><td>33250A</td><td></td></tr><tr><td>Syringe</td><td>Hamilton</td><td>84505</td><td></td></tr><tr><td>Paper Clamp</td><td>ADAMS</td><td>3300-50-3848</td><td></td></tr><tr><td>Oven</td><td>Fisher Scientific</td><td>280A</td><td></td></tr><tr><td>Multimeter</td><td>OMEGA</td><td>HHM25</td><td></td></tr><tr><td>Micro-milling machine</td><td>AEROTECH</td><td>ABL1500 stages/A3200 Npaq controller</td><td></td></tr><tr><td>End mill</td><td>ULTRATOOL</td><td>708473</td><td></td></tr><tr><td>AxioVision</td><td>Zeiss</td><td>Version 4.8</td><td></td></tr></tbody></table>

development of a 3d graphene electrode dielectrophoretic device

采用50μm厚的石墨烯纸和100μm的双面胶带的新型三维电极微型装置的设计和制作方法进行说明。该协议详细说明了程序，以构建一个通用的，可重复使用的，多个层，夹层介电电泳室。具体而言，为50微米×0.7 2cm×2cm的石墨烯纸和5层的双面胶带6层交替地叠在一起，然后夹紧到载玻片上。然后一个700微米直径的微孔中穿过叠层结构用计算机控制的微型钻孔机钻孔。邻近的石墨烯层之间的带层的绝缘性能有保证的电阻测试。银导电环氧树脂连接的石墨烯纸交替层形成的石墨烯纸和外部铜导线电极之间的稳定连接。成品器件，然后夹紧并密封到载玻片上。电场梯度在t蓝本他的多层器件。 6微米的聚苯乙烯珠介电行为进行了论证，在1毫米深的微孔，具有中等电导率从0.0001 S / m至1.3 S / m的，并应用于信号频率从100 Hz至10 MHz。负的介电电泳反应，观察在三个维度在大部分导电频率空间和交叉频率值与先前文献报道值相一致。该设备并没有阻止交流电电渗和电热流动，这发生在低频和高频区域，分别为。在此设备中使用的石墨烯纸是多才多艺，随后可能作为一个生物传感器后的介电电泳的刻画是完整的。

在6微米的聚苯乙烯珠的介电电泳实验是在0.38 立方毫米的圆柱形微孔进行。结果表明，一个三维层叠的石墨烯纸为基础的装置可以说明类似的介电电泳的签名作为三维金属箔层压装置20，21，传统的二维金属电极26，27，和二维绝缘体装置25。在下面的实验中，一个15 V 峰峰值 AC信号被施加并且频率从100赫兹到10 MHz 30改变。定性DEP结果在时间0现场应用...

Watch this Scientific Journal Video about Development of a 3D Graphene Electrode Dielectrophoretic Device at JoVE.com

Development of a 3D Graphene Electrode Dielectrophoretic Device

与高通量电位A微型用于演示的三维（3D）介电电泳（DEP）的新颖材料。石墨烯纳米薄片纸，双面胶带交替堆叠;一个700微米的微井钻横切层。的聚苯乙烯小珠的DEP行为表现在微井。

三维石墨电极介电泳装置的研制

The design and fabrication of a novel 3D electrode microdevice using 50 &#181;m thick graphene paper and 100 &#181;m double sided tape is described. The ...

development-of-a-3d-graphene-electrode-dielectrophoretic-device

Research

JoVE Journal

Engineering

11.9K 次观看.  Michigan Technological University. 与高通量电位A微型用于演示的三维（3D）介电电泳（DEP）的新颖材料。石墨烯纳米薄片纸，双面胶带交替堆叠;一个700微米的微井钻横切层。的聚苯乙烯小珠的DEP行为表现在微井。 

视频: Development of a 3D Graphene Electrode Dielectrophoretic Device

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities

Owing to its relativistic low-energy charge carriers, the interaction between graphene and various impurities leads to a wealth of new physics and degrees of freedom to control electronic devices. In particular, the behavior of graphene&#8217;s charge carriers in response to potentials from charged Coulomb impurities is predicted to differ significantly from that of most materials. Scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) can provide detailed information on both the spatial and energy dependence of graphene&#39;s electronic structure in the presence of a charged impurity.&#160;The design of a hybrid impurity-graphene device, fabricated using controlled deposition of impurities onto a back-gated graphene surface, has enabled several novel methods for controllably tuning graphene&#8217;s electronic properties.1-8 Electrostatic gating enables control of the charge carrier density in graphene and the ability to reversibly tune the charge2 and/or molecular5 states of an impurity. This paper outlines the process of fabricating a gate-tunable graphene device decorated with individual Coulomb impurities for combined STM/STS studies.2-5 These studies provide valuable insights into the underlying physics, as well as signposts for designing hybrid graphene devices.

This paper details the fabrication process of a gate-tunable graphene device, decorated with Coulomb impurities for scanning tunneling microscopy studies. Mapping the spatially dependent electronic structure of graphene in the presence of charged impurities unveils the unique behavior of its relativistic charge carriers in response to a local Coulomb potential.

对于扫描隧道显微学与库仑杂质制造门可调谐石墨烯器件

Owing to its relativistic low-energy charge carriers, the interaction between graphene and various impurities leads to a wealth of new physics and degrees ...

科研

工程学

Synthesis and Functionalization of 3D Nano-graphene Materials: Graphene Aerogels and Graphene Macro Assemblies

Efforts to assemble graphene into three-dimensional monolithic structures have been hampered by the high cost and poor processability of graphene. Additionally, most reported graphene assemblies are held together through physical interactions (e.g., van der Waals forces) rather than chemical bonds, which limit their mechanical strength and conductivity. This video method details recently developed strategies to fabricate mass-producible, graphene-based bulk materials derived from either polymer foams or single layer graphene oxide. These materials consist primarily of individual graphene sheets connected through covalently bound carbon linkers. They maintain the favorable properties of graphene such as high surface area and high electrical and thermal conductivity, combined with tunable pore morphology and exceptional mechanical strength and elasticity. This flexible synthetic method can be extended to the fabrication of polymer/carbon nanotube (CNT) and polymer/graphene oxide (GO) composite materials. Furthermore, additional post-synthetic functionalization with anthraquinone is described, which enables a dramatic increase in charge storage performance in supercapacitor applications.

This video method describes the synthesis of high surface area, monolithic 3D graphene-based materials derived from polymer precursors as well as single layer graphene oxide.

合成和3D纳米石墨烯材料的功能化:石墨烯气凝胶和石墨烯宏组件

Efforts to assemble graphene into three-dimensional monolithic structures have been hampered by the high cost and poor processability of graphene. ...

Flow-assisted Dielectrophoresis: A Low Cost Method for the Fabrication of High Performance Solution-processable Nanowire Devices

Flow-assisted dielectrophoresis (DEP) is an efficient self-assembly method for the controllable and reproducible positioning, alignment, and selection of nanowires. DEP is used for nanowire analysis, characterization, and for solution-based fabrication of semiconducting devices. The method works by applying an alternating electric field between metallic electrodes. The nanowire formulation is then dropped onto the electrodes which are on an inclined surface to create a flow of the formulation using gravity. The nanowires then align along the gradient of the electric field and in the direction of the liquid flow. The frequency of the field can be adjusted to select nanowires with superior conductivity and lower trap density. 
In this work, flow-assisted DEP is used to create nanowire field effect transistors. Flow-assisted DEP has several advantages: it allows selection of nanowire electrical properties; control of nanowire length; placement of nanowires in specific areas; control of orientation of nanowires; and control of nanowire density in the device. 
The technique can be expanded to many other applications such as gas sensors and microwave switches. The technique is efficient, quick, reproducible, and it uses a minimal amount of dilute solution making it ideal for the testing of novel nanomaterials. Wafer scale assembly of nanowire devices can also be achieved using this technique, allowing large numbers of samples for testing and large-area electronic applications.

In this paper, flow assisted dielectrophoresis is demonstrated for the self-assembly of nanowire devices. The fabrication of a silicon nanowire field effect transistor is shown as an example.

流动辅助介: 一种低成本的制备高性能溶液可纳米线器件的方法

Flow-assisted dielectrophoresis (DEP) is an efficient self-assembly method for the controllable and reproducible positioning, alignment, and selection of ...

Using Graphene Liquid Cell Transmission Electron Microscopy to Study in Situ Nanocrystal Etching

Graphene liquid cell electron microscopy provides the ability to observe nanoscale chemical transformations and dynamics as the reactions are occurring in liquid environments. This manuscript describes the process for making graphene liquid cells through the example of graphene liquid cell transmission electron microscopy (TEM) experiments of gold nanocrystal etching. The protocol for making graphene liquid cells involves coating gold, holey-carbon TEM grids with chemical vapor deposition graphene and then using those graphene-coated grids to encapsulate liquid between two graphene surfaces. These pockets of liquid, with the nanomaterial of interest, are imaged in the electron microscope to see the dynamics of the nanoscale process, in this case the oxidative etching of gold nanorods. By controlling the electron beam dose rate, which modulates the etching species in the liquid cell, the underlying mechanisms of how atoms are removed from nanocrystals to form different facets and shapes can be better understood. Graphene liquid cell TEM has the advantages of high spatial resolution, compatibility with traditional TEM holders, and low start-up costs for research groups. Current limitations include delicate sample preparation, lack of flow capability, and reliance on electron beam-generated radiolysis products to induce reactions. With further development and control, graphene liquid cell may become a ubiquitous technique in nanomaterials and biology, and is already being used to study mechanisms governing growth, etching, and self-assembly processes of nanomaterials in liquid on the single particle level.

Using Graphene Liquid Cell Transmission Electron Microscopy to Study in Situ Nanocrystal Etching

Graphene liquid cell electron microscopy can be used to observe nanocrystal dynamics in a liquid environment with greater spatial resolution than other liquid cell electron microscopy techniques. Etching premade nanocrystals and following their shape using graphene liquid cell Transmission Electron Microscopy can yield important mechanistic information about nanoparticle transformations.

用石墨烯液细胞透射电镜研究原位纳米晶蚀刻

Graphene liquid cell electron microscopy provides the ability to observe nanoscale chemical transformations and dynamics as the reactions are occurring in ...

化学

Fabrication of Three-Dimensional Graphene-Based Polyhedrons via Origami-Like Self-Folding

The assembly of two-dimensional (2D) graphene into three-dimensional (3D) polyhedral structures while preserving the graphene's excellent inherent properties has been of great interest for the development of novel device applications. Here, fabrication of 3D, microscale, hollow polyhedrons (cubes) consisting of a few layers of 2D graphene or graphene oxide sheets via an origami-like self-folding process is described. This method involves the use of polymer frames and hinges, and aluminum oxide/chromium protection layers that reduce tensile, spatial, and surface tension stresses on the graphene-based membranes when the 2D nets are transformed into 3D cubes. The process offers control of the size and shape of the structures as well as parallel production. In addition, this approach allows the creation of surface modifications by metal patterning on each face of the 3D cubes. Raman spectroscopy studies show the method allows the preservation of the intrinsic properties of the graphene-based membranes, demonstrating the robustness of our method.

Fabrication of Three-Dimensional Graphene-Based Polyhedrons via Origami-Like Self-Folding

Here, we present a protocol for fabrication of 3D graphene-based polyhedrons via origami-like self-folding.

基于折纸式自折叠的三维石墨烯正多面体的制备

The assembly of two-dimensional (2D) graphene into three-dimensional (3D) polyhedral structures while preserving the graphene's excellent inherent ...

Preparation of Graphene Liquid Cells for the Observation of Lithium-ion Battery Material

In this work, we introduce the preparation of graphene liquid cells (GLCs), encapsulating both electrode materials and organic liquid electrolytes between two graphene sheets, and the facile synthesis of one-dimensional nanostructures using electrospinning. The GLC enables in situ transmission electron microscopy (TEM) for the lithiation dynamics of electrode materials. The in situ GLC-TEM using an electron beam for both imaging and lithiation can utilize not only realistic battery electrolytes, but also the high-resolution imaging of various morphological, phase, and interfacial transitions.

Here, we present a protocol for the fabrication and preparation of a graphene liquid cell for in situ transmission electron microscopy observation, along with a synthesis of electrode materials and electrochemical battery cell tests.

锂离子电池材料用石墨烯液位的制备

In this work, we introduce the preparation of graphene liquid cells (GLCs), encapsulating both electrode materials and organic liquid electrolytes between ...

Production of a Strain-Measuring Device with an Improved 3D Printer

A traditional strain measurement sensor needs to be electrified and is susceptible to electromagnetic interference. In order to solve the fluctuations in the analog electrical signal in a traditional strain gauge operation, a new strain measurement method is presented here. It uses a photographic technique to display the strain change by amplifying the change of the pointer displacement of the mechanism. A visual polydimethylsiloxane (PDMS) lens with a focal length of 7.16 mm was added to a smartphone camera to generate a lens group acting as a microscope to capture images. It had an equivalent focal length of 5.74 mm. Acrylonitrile butadiene styrene (ABS) and nylon amplifiers were used to test the influence of different materials on the sensor performance. The production of the amplifiers and PDMS lens is based on improved 3D printing technology. The data obtained were compared with the results from finite element analysis (FEA) to verify their validity. The sensitivity of the ABS amplifier was 36.03 &plusmn; 1.34 &#181;&epsilon;/&#181;m, and the sensitivity of the nylon amplifier was 36.55 &plusmn; 0.53 &#181;&epsilon;/&#181;m.

This work presents a strain measurement sensor consisting of an amplification mechanism and a polydimethylsiloxane microscope manufactured using an improved 3D printer.

使用改进的 3D 打印机生产应变测量设备

A traditional strain measurement sensor needs to be electrified and is susceptible to electromagnetic interference. In order to solve the fluctuations in ...

Evaluating the Electrochemical Properties of Supercapacitors using the Three-Electrode System

The three-electrode system is a basic and general analytical platform for investigating the electrochemical performance and characteristics of energy storage systems at the material level. Supercapacitors are one of the most important emergent energy storage systems developed in the past decade. Here, the electrochemical performance of a supercapacitor was evaluated using a three-electrode system with a potentiostat device. The three-electrode system consisted of a working electrode (WE), reference electrode (RE), and counter electrode (CE). The WE is the electrode where the potential is controlled and the current is measured, and it is the target of research. The RE acts as a reference for measuring and controlling the potential of the system, and the CE is used to complete the closed circuit to enable electrochemical measurements. This system provides accurate analytical results for evaluating electrochemical parameters such as the specific capacitance, stability, and impedance through cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). Several experimental design protocols are proposed by controlling the parameter values of the sequence when using a three-electrode system with a potentiostat device to evaluate the electrochemical performance of supercapacitors. Through these protocols, the researcher can set up a three-electrode system to obtain reasonable electrochemical results for assessing the performance of supercapacitors.

The protocol describes the evaluation of various electrochemical properties of supercapacitors using a three-electrode system with a potentiostat device.

使用三电极系统评估超级电容器的电化学性质

The three-electrode system is a basic and general analytical platform for investigating the electrochemical performance and characteristics of energy ...

Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection

In the current study, graphene and its derivatives have been investigated and used for many applications, including electronics, sensing, energy storage, and photocatalysis. Synthesis and fabrication of high quality, good uniformity, and low defects graphene are critical for high-performance and highly sensitive devices. Among many synthesis methods, chemical vapor deposition (CVD), considered a leading approach to manufacture graphene, can control the number of graphene layers and yield high-quality graphene. CVD graphene needs to be transferred from the metal substrates on which it is grown onto&#160;insulating substrates for practical applications. However, separation and transferring of graphene onto new substrates are challenging for a uniform layer without damaging or affecting graphene&#39;s structures and properties. Additionally, electrolyte-gated graphene field-effect transistor (EGGFET) has been demonstrated for its wide applications in various biomolecular detections because of its high sensitivity and standard device configuration. In this article, poly (methyl methacrylate) (PMMA)-assisted graphene transferring approach, fabrication of graphene field-effect transistor (GFET), and biomarker immunoglobulin G (IgG) detection are demonstrated. Raman spectroscopy and atomic force microscopy were applied to characterize the transferred graphene. The method is shown to be a practical approach for transferring clean and residue-free graphene while preserving the underlying graphene lattice onto an insulating substrate for electronics or biosensing applications.

The present protocol demonstrates the development of electrolyte-gated graphene field-effect transistor (EGGFET) biosensor and its application in biomarker immunoglobulin G (IgG) detection.

用于生物标志物检测的电解质门控石墨烯场效应晶体管的开发与功能化

In the current study, graphene and its derivatives have been investigated and used for many applications, including electronics, sensing, energy storage, ...

用单层石墨烯包覆 CryoEM 网格以改善冷冻样品制备

Application of Monolayer Graphene to Cryo-Electron Microscopy Grids for High-resolution Structure Determination

In cryogenic electron microscopy (cryoEM), purified macromolecules are applied to a grid bearing a holey carbon foil; the molecules are then blotted to remove excess liquid and rapidly frozen in a roughly 20-100 nm thick layer of vitreous ice, suspended across roughly 1 &#181;m wide foil holes. The resulting sample is imaged using cryogenic transmission electron microscopy, and after image processing using suitable software, near-atomic resolution structures can be determined. Despite cryoEM&#39;s widespread adoption, sample preparation remains a severe bottleneck in cryoEM workflows, with users often encountering challenges related to samples behaving poorly in the suspended vitreous ice. Recently, methods have been developed to modify cryoEM grids with a single continuous layer of graphene, which acts as a support surface that often increases particle density in the imaged area and can reduce interactions between particles and the air-water interface. Here, we provide detailed protocols for the application of graphene to cryoEM grids and for rapidly assessing the relative hydrophilicity of the resulting grids. Additionally, we describe an EM-based method to confirm the presence of graphene by visualizing its characteristic diffraction pattern. Finally, we demonstrate the utility of these graphene supports by rapidly reconstructing a 2.7 &#197; resolution density map of a Cas9 complex using a pure sample at a relatively low concentration.

作者聚焦：在显微镜网格上使用石墨烯单层增强 CryoEM 样品制备 

The application of support layers to cryogenic electron microscopy (cryoEM) grids can increase particle density, limit interactions with the air-water interface, reduce beam-induced motion, and improve the distribution of particle orientations. This paper describes a robust protocol for coating cryoEM grids with a monolayer of graphene for improved cryo-sample preparation.

单层石墨烯在冷冻电子显微镜网格中的应用，用于高分辨率结构测定

In cryogenic electron microscopy (cryoEM), purified macromolecules are applied to a grid bearing a holey carbon foil; the molecules are then blotted to ...