Name: a high performance impedance-based platform for evaporation rate detection
Uploaded: 2016-10-17T15:00:00.000+00:00
Duration: 6 min 39 s
Description: Watch this Scientific Journal Video about A High Performance Impedance-based Platform for Evaporation Rate Detection at JoVE.com

这项工作得到了科技部，台湾教育部科技部105-2627-B-005-002主办，在授予数量MOST 104-2221-E-241-001-MY3和。

1.实验芯片模块<ol><li> 制造的氧化铟锡（ITO）通过光刻和化学湿法蚀刻工艺电极片 <ol><li>商业获取ITO基板（370毫米×480毫米×0.5毫米（长x宽x高））与2,600 ITO层（见材料清单）。切片ITO基板以90mm的×90毫米×0.5毫米的玻璃切割器用于在4英寸对准ITO电极图案化工艺的尺寸。 </li><li>使用超声波清洗机清洗ITO玻璃用丙酮，然后用去离子水，每次15分钟。擦干ITO玻璃清洁干燥空气。 </li><li>分配溶于5ml阳性光致抗蚀剂溶液涂布在ITO玻璃的表面上。 </li><li>使用旋涂机，在500×g离心30秒，以产生均匀的光致抗蚀剂层。在90℃在热板上，然后烘烤5分钟以在光致抗蚀剂除去多余的溶剂。 </li><li>露出ITO玻璃对紫外线的14毫瓦为3.1秒吨436纳米hrough与设计的图案的膜的光掩模（参见材料清单）。 </li><li>沉浸在60ml发展溶液样品在23℃下30秒，以开发图案化的路线。在120℃在热板上，然后烘烤10分钟以硬化光致抗蚀剂和提高光致抗蚀剂粘附性。 </li><li>浸入样品3分钟在60毫升在80℃蚀刻溶液来蚀刻未受保护的ITO层。 </li><li>浸入样品1分钟在60毫升丙酮中以在ITO玻璃的表面除去光致抗蚀剂。 </li><li>切片ITO玻璃成62毫米×35毫米为实验ITO电极芯片（ 图1）用玻璃切割器的尺寸。 </li></ol></li></ol><img alt="图1" src="/files/ftp_upload/54575/54575fig1.jpg" /> 图1:ITO电极芯片的带8中的电极图案的路由的示出制造的ITO芯片。有15个电极<html>尺寸为2mm×8 mm，在侧边缘，并且中央两条路由共享相同的电极。在测试以及每对电极指之间的距离为7毫米。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/54575/54575fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <ol start="2"><li> 构建实验芯片模块 <ol><li>清洗用超声波清洁器商用8孔硅氧烷阵列， 如图2用洗涤剂，然后用去离子水洗涤，然后95％的乙醇，然后用去离子水，每次15分钟。 </li><li>干燥吹入清洁干燥空气在8孔硅阵列。 </li><li>按以形成实验芯片模块（ 图3）在8孔硅氧烷数组在ITO芯片。紧紧硅阵列和ITO芯片绑定。 </li></ol></li></ol>54575fig2.jpg"/&gt; 图2: 硅以及阵列商用8孔硅阵列可同时容纳8测试样品。每个孔的大小为11mm×8毫米×8.5毫米（长x宽x高）。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/54575/54575fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/54575/54575fig3.jpg" /> 图3:实验芯片模块的ITO电极芯片附着有8孔硅阵列以形成实验芯片模块。硅阵列和ITO芯片之间的粘合性强。因此，在硅阵列和ITO芯片可以用于粘合在一起，没有任何粘合物质。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/54575/54575fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 2.阻抗测量<ol><li>连接个人计算机，锁定放大器，和开关继电器以形成阻抗读出模块， 如图4。 </li></ol><img alt="图4" src="/files/ftp_upload/54575/54575fig4.jpg" /> 图4:在基于阻抗的装置的原理图锁相放大器，开关继电器，和个人计算机构成的阻抗读出模块。商用相位敏感锁定放大器被用来发送和提取电信号。连接各种ITO芯片的自制开关继电器电路用于指定哪个井和ITO芯片进行测试。总共6芯片可以连接到开关继电器以时间共享的方式，指定48个样本。相电阻和测试溶液的信号相移被连续记录在个人计算机上对整个evaporat实时离子的过程。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/54575/54575fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <ol start="2"><li>把实验芯片模块插入开关继电器的插座。 </li><li>输入参数中的计算机程序。输入信号频率（1千赫），指定的井号（0-7），则执行周期（100），和文件名（HA）。 </li></ol> 3.蒸发实验<ol><li>在水中于0，0.05，0.5和w / v的％制备四种2.5毫升透明质酸溶液。发生在一个小瓶测量14.75毫米×45毫米×8毫米（OD x高x ID），每一块有2.5 ml样品液。 </li><li>对于每种溶液，加入0.5 ml样品溶液，以在ITO芯片模块的单井。 </li><li>称重并通过电子天平机记录每个小瓶的初始重量。 </li><li>执行该计算机程序，以自动测量和记录实时同相电阻和信号p在ITO芯片上指定井HASE转变。 </li><li>在由称重方法和阻抗方法都在同一个地方同时开始蒸发实验。 </li><li>称重并通过电子天平机在预定的时间点记录各小瓶的重量。 </li><li>在称重法和阻抗法分析收集的数据。19 </li></ol>

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作者什么都没有透露。

蒸发测量在这个基于阻抗的检测关键步骤是测试的解决方案的制备。去离子水不能由于其巨大的阻抗被使用。相反，使用含有导电离子的自来水制备用于实验透明质酸溶液。但是，自来水的电性能不是使用恒定的。因此，归一化，如相对蒸发速率，以水在这项研究中，获得通过作为蒸发的替代指标。该技术的限制是，测试的解决方案必须有电化学表征导电离子。 <p class="jov...

蒸发是一种液体汽化并沿水集体体的气 - 液界面发生。表面附近的水分子，由于水分子的碰撞成为能够从液体中逸出。蒸发速度蒸发的过程中，一个重要的关键因素。一般地，平衡或体积管1-3被广泛使用的，以检测溶液的蒸发。然而，它需要很长的时间来测量的蒸发速率由于平衡或体积管的精度的限制。出于这个原因，一个响应和高灵敏度的仪器必须开发探入蒸发过程的细节。 电化学阻抗谱（EIS）是一个快速响应，在原位阻抗检测电化学系统表征4方面敏感和有效的实验手段。因此，交流阻抗可以以各种呸施加LDS， 如最近对细胞行为5项研究，生物分析检测6-7，电解8，导电聚合物9和电化学提取10。尽管EIS系统已成功应用于多种学科的应用，存在其应用蒸发研究的一个非常小的数字出版物。 透明质酸，高分子量的多糖具有较强的水结合的潜力，是用于化妆品应用公知的保湿剂。一个透明质酸分子可绑定多达500个水分子11和达到1000倍原来体积12。透明质酸的极少量可具有保湿功能13-14。由于高的保湿性，透明质酸已经成为化妆品的保湿剂的产品与世界各地的15个高的商业价值的重要组成部分。 ŧ他的研究提出了基于阻抗新颖装置具有高速检测，小体积的样品的要求，和多个样品测量16-19的方法。它是为重点的解决方案，以此来验证比传统的称重方式创新的检测机制的优越性之间的相对蒸发速率比较。

<table><tbody><tr><td>95% ethanol</td><td>Echo Chemical Co., Ltd., Miaoli, Taiwan</td><td>484000001103C-00EC</td><td></td></tr><tr><td>Acetone</td><td>Avantor Performance Materials Inc., Center Valley, PA, USA</td><td>JTB-9005-68</td><td></td></tr><tr><td>Development solution</td><td>Kemitek Industrial Crop., Hsinchu, Taiwan</td><td>12F01031</td><td>KTD-1</td></tr><tr><td>Etching solution</td><td>eSolv Technology Co., Taipei, Taiwan</td><td></td><td>EG-462</td></tr><tr><td>Hyaluronic acid</td><td>Shandong Freda Biopharm Co., Ltd., Jinan, China</td><td>1010212</td><td>Molecular weight 980k, Cosmetic Grade</td></tr><tr><td>Photoresist solution</td><td>AZ Electronic Materials Taiwan Co., Ltd., Hsinchu, Taiwan</td><td>65101M19</td><td>AZ6112</td></tr><tr><td>8-well silicone array</td><td>Greiner bio-one Inc., Frickenhausen, Baden-W&amp;uuml;rttemberg, Germany</td><td>FlexiPERM</td><td></td></tr><tr><td>ITO glass</td><td>GemTech Optoelectronics Co., Taoyuan, Taiwan</td><td></td><td></td></tr><tr><td>Vial</td><td>Sigma-Aldrich Co. LLC., St. Louis, MO, USA</td><td>854190</td><td></td></tr><tr><td>Film photomask</td><td>Taiwan Mesh Co., Ltd, Taoyuan, Taiwan</td><td></td><td></td></tr><tr><td>Lock-in amplifier</td><td>Stanford Research Systems, Inc., Palo Alto, CA, USA</td><td>SR830</td><td></td></tr><tr><td>Switch relay</td><td>Instrument Technology Research Center, National Applied Research Laboratories, Hsinchu, Taiwan</td><td></td><td></td></tr><tr><td>Electronic balance machine</td><td>Radwag Inc., Radom, Poland</td><td>AS 60/220/C/2</td><td></td></tr></tbody></table>

a high performance impedance-based platform for evaporation rate detection

本文描述了用于在检测到的蒸发速率的新颖的基于阻抗的平台的方法。该模型复合透明质酸这里用于演示的目的。以具有各种浓度的溶液的湿润剂的模型化合物的多个蒸发试验为比较目的进行的。常规的减肥方法被称为蒸发率检测的最简单的，但费时，测量技术。然而，一个明显的缺点是，大量的样品需要和多个样本测试不能在同一时间进行。在文献首次电阻抗传感芯片被成功地应用到在时间共享，连续和自动地实时蒸发调查。而且，试验样品的少0.5毫升需要在此基于阻抗的装置，和一个大的阻抗变化显示各稀soluti之间附件。所提出的高灵敏度和快速响应阻抗传感系统发现超越蒸发率检测方面的传统的减肥方法。

在蒸发过程中，在测试溶液中的导电离子成为浓的减少溶液体积，以及该溶液的阻抗降低。测定重量损失，并在每个测试溶液的蒸发进展阻抗降低的速率。为了比较的目的，在体重损失和阻抗降低的速率的数据标准化为水，然后在图5中绘制在一起。如在图5中所示，重量损失表明了相同的倾向的阻抗，并表明，该相对蒸发速率到水蒸发与透明质酸浓度降低。然而，大量的?...

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A High Performance Impedance-based Platform for Evaporation Rate Detection

本文提出了蒸发率检测解决方案的基于阻抗的设备。它提供了明显的优势比传统的减肥方法:快速响应，高灵敏度的检测，一个小样本的要求，多样品测量，并便于拆卸清洗和再利用的目的。

蒸发速率检测一种基于阻抗高性能平台

This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was ...

a-high-performance-impedance-based-platform-for-evaporation-rate

Universidad de Cartagena UDEC

Research

JoVE Journal

Engineering

6.5K 次观看.  Hungkuang University. 本文提出了蒸发率检测解决方案的基于阻抗的设备。它提供了明显的优势比传统的减肥方法:快速响应，高灵敏度的检测，一个小样本的要求，多样品测量，并便于拆卸清洗和再利用的目的。 

视频: A High Performance Impedance-based Platform for Evaporation Rate Detection

The Visual Colorimetric Detection of Multi-nucleotide Polymorphisms on a Pneumatic Droplet Manipulation Platform

A simple and visual method to detect multi-nucleotide polymorphism (MNP) was performed on a pneumatic droplet manipulation platform on an open surface. This approach to colorimetric DNA detection was based on the hybridization-mediated growth of gold nanoparticle probes (AuNP probes). The growth size and configuration of the AuNP are dominated by the number of DNA samples hybridized with the probes. Based on the specific size- and shape-dependent optical properties of the nanoparticles, the number of mismatches in a sample DNA fragment to the probes is able to be discriminated. The tests were conducted via droplets containing reagents and DNA samples respectively, and were transported and mixed on the pneumatic platform with the controlled pneumatic suction of the flexible PDMS-based superhydrophobic membrane. Droplets can be delivered simultaneously and precisely on an open-surface on the proposed pneumatic platform that is highly biocompatible with no side effect of DNA samples inside the droplets. Combining the two proposed methods, the multi-nucleotide polymorphism can be detected at sight on the pneumatic droplet manipulation platform; no additional instrument is required. The procedure from installing the droplets on the platform to the final result takes less than 5 min, much less than with existing methods. Moreover, this combined MNP detection approach requires a sample volume of only 10 &#181;l in each operation, which is remarkably less than that of a macro system.

This work presents a simple and visual method to detect multi-nucleotide polymorphisms on a pneumatic droplet manipulation platform. With the proposed method, the entire experiment, including droplet manipulation and detection of multi-nucleotide polymorphisms, can be performed near 23 &#176;C without the aid of advanced instruments.

在气动操纵液滴平台多核苷酸多态性的视觉比色法检测

A simple and visual method to detect multi-nucleotide polymorphism (MNP) was performed on a pneumatic droplet manipulation platform on an open surface. ...

科研

遗传学

Exploring the Effects of Atmospheric Forcings on Evaporation: Experimental Integration of the Atmospheric Boundary Layer and Shallow Subsurface

Evaporation is directly influenced by the interactions between the atmosphere, land surface and soil subsurface. This work aims to experimentally study evaporation under various surface boundary conditions to improve our current understanding and characterization of this multiphase phenomenon as well as to validate numerical heat and mass transfer theories that couple Navier-Stokes flow in the atmosphere and Darcian flow in the porous media. Experimental data were collected using a unique soil tank apparatus interfaced with a small climate controlled wind tunnel. The experimental apparatus was instrumented with a suite of state of the art sensor technologies for the continuous and autonomous collection of soil moisture, soil thermal properties, soil and air temperature, relative humidity, and wind speed. This experimental apparatus can be used to generate data under well controlled boundary conditions, allowing for better control and gathering of accurate data at scales of interest not feasible in the field. Induced airflow at several distinct wind speeds over the soil surface resulted in unique behavior of heat and mass transfer during the different evaporative stages.

A protocol for the design and construction of a soil tank interfaced to a small climate controlled wind tunnel to study the effects of atmospheric forcings on evaporation is presented. Both the soil tank and wind tunnel are instrumented with sensor technologies for the continuous in situ measurement of environmental conditions.

在探索大气蒸发强迫的影响:大气边界层和浅地层的实验整合

Evaporation is directly influenced by the interactions between the atmosphere, land surface and soil subsurface. This work aims to experimentally study ...

环境科学

Fluorescence detection methods for microfluidic droplet platforms

The development of microfluidic platforms for performing chemistry and biology has in large part been driven by a range of potential benefits that accompany system miniaturisation. Advantages include the ability to efficiently process nano- to femoto- liter volumes of sample, facile integration of functional components, an intrinsic predisposition towards large-scale multiplexing, enhanced analytical throughput, improved control and reduced instrumental footprints.1
In recent years much interest has focussed on the development of droplet-based (or segmented flow) microfluidic systems and their potential as platforms in high-throughput experimentation.2-4 Here water-in-oil emulsions are made to spontaneously form in microfluidic channels as a result of capillary instabilities between the two immiscible phases. Importantly, microdroplets of precisely defined volumes and compositions can be generated at frequencies of several kHz. Furthermore, by encapsulating reagents of interest within isolated compartments separated by a continuous immiscible phase, both sample cross-talk and dispersion (diffusion- and Taylor-based) can be eliminated, which leads to minimal cross-contamination and the ability to time analytical processes with great accuracy. Additionally, since there is no contact between the contents of the droplets and the channel walls (which are wetted by the continuous phase) absorption and loss of reagents on the channel walls is prevented.
Once droplets of this kind have been generated and processed, it is necessary to extract the required analytical information. In this respect the detection method of choice should be rapid, provide high-sensitivity and low limits of detection, be applicable to a range of molecular species, be non-destructive and be able to be integrated with microfluidic devices in a facile manner. To address this need we have developed a suite of experimental tools and protocols that enable the extraction of large amounts of photophysical information from small-volume environments, and are applicable to the analysis of a wide range of physical, chemical and biological parameters. Herein two examples of these methods are presented and applied to the detection of single cells and the mapping of mixing processes inside picoliter-volume droplets. We report the entire experimental process including microfluidic chip fabrication, the optical setup and the process of droplet generation and detection.

Droplet-based microfluidic platforms are promising candidates for high throughput experimentation since they are able to generate picoliter, self-compartmentalized vessels inexpensively at kHz rates. Through integration with fast, sensitive and high resolution fluorescence spectroscopic methods, the large amounts of information generated within these systems can be efficiently extracted, harnessed and utilized.

荧光检测方法，为微流体液滴平台

The development of microfluidic platforms for performing chemistry and biology has in large part been driven by a range of potential benefits that ...

生物工程

Taking Advantage of Reduced Droplet-surface Interaction to Optimize Transport of Bioanalytes in Digital Microfluidics

Digital microfluidics (DMF), a technique for manipulation of droplets, is a promising alternative for the development of &#8220;lab-on-a-chip&#8221; platforms. Often, droplet motion relies on the wetting of a surface, directly associated with the application of an electric field; surface interactions, however, make motion dependent on droplet contents, limiting the breadth of applications of the technique.
Some alternatives have been presented to minimize this dependence. However, they rely on the addition of extra chemical species to the droplet or its surroundings, which could potentially interact with droplet moieties. Addressing this challenge, our group recently developed Field-DW devices to allow the transport of cells and proteins in DMF, without extra additives.
Here, the protocol for device fabrication and operation is provided, including the electronic interface for motion control. We also continue the studies with the devices, showing that multicellular, relatively large, model organisms can also be transported, arguably unaffected by the electric fields required for device operation.

The protocol for fabrication and operation of field dewetting devices (Field-DW) is described, as well as the preliminary studies of the effects of electric fields on droplet contents.

以减少液滴表面的相互作用来优化Bioanalytes运输中的数字微流体

Digital microfluidics (DMF), a technique for manipulation of droplets, is a promising alternative for the development of &#8220;lab-on-a-chip&#8221; ...

工程学

Quantification and Size-profiling of Extracellular Vesicles Using Tunable Resistive Pulse Sensing

Extracellular vesicles (EVs), including &#8216;microvesicles&#8217; and &#8216;exosomes&#8217;, are highly abundant in bodily fluids. Recent years have witnessed a tremendous increase in interest in EVs. EVs have been shown to play important roles in various physiological and pathological processes, including coagulation, immune responses, and cancer. In addition, EVs have potential as therapeutic agents, for instance as drug delivery vehicles or as regenerative medicine. Because of their small size (50 to 1,000 nm) accurate quantification and size profiling of EVs is technically challenging.
This protocol describes how tunable resistive pulse sensing (tRPS) technology, using the qNano system, can be used to determine the concentration and size of EVs. The method, which relies on the detection of EVs upon their transfer through a nano sized pore, is relatively fast, suffices the use of small sample volumes and does not require the purification and concentration of EVs. Next to the regular operation protocol an alternative approach is described using samples spiked with polystyrene beads of known size and concentration. This real-time calibration technique can be used to overcome technical hurdles encountered when measuring EVs directly in biological fluids.

Extracellular vesicles play important roles in physiological and pathological processes, including coagulation, immune responses, and cancer or as potential therapeutic agents in drug delivery or regenerative medicine. This protocol presents methods for the quantification and size characterization of isolated and non-isolated extracellular vesicles in various fluids using tunable resistive pulse sensing.

定量和大小分析外囊泡的使用可调电阻脉冲检测

Extracellular vesicles (EVs), including &#8216;microvesicles&#8217; and &#8216;exosomes&#8217;, are highly abundant in bodily fluids. Recent years have ...

A Microfluidic-based Electrochemical Biochip for Label-free DNA Hybridization Analysis

Miniaturization of analytical benchtop procedures into the micro-scale provides significant advantages in regards to reaction time, cost, and integration of pre-processing steps. Utilizing these devices towards the analysis of DNA hybridization events is important because it offers a technology for real time assessment of biomarkers at the point-of-care for various diseases. However, when the device footprint decreases the dominance of various physical phenomena increases. These phenomena influence the fabrication precision and operation reliability of the device. Therefore, there is a great need to accurately fabricate and operate these devices in a reproducible manner in order to improve the overall performance. Here, we describe the protocols and the methods used for the fabrication and the operation of a microfluidic-based electrochemical biochip for accurate analysis of DNA hybridization events. The biochip is composed of two parts: a microfluidic chip with three parallel micro-channels made of polydimethylsiloxane (PDMS), and a 3 x 3 arrayed electrochemical micro-chip. The DNA hybridization events are detected using electrochemical impedance spectroscopy (EIS) analysis. The EIS analysis enables monitoring variations of the properties of the electrochemical system that are dominant at these length scales. With the ability to monitor changes of both charge transfer and diffusional resistance with the biosensor, we demonstrate the selectivity to complementary ssDNA targets, a calculated detection limit of 3.8 nM, and a 13% cross-reactivity with other non-complementary ssDNA following 20 min&#160;of incubation. This methodology can improve the performance of miniaturized devices by elucidating on the behavior of diffusion at the micro-scale regime and by enabling the study of DNA hybridization events.

We present a microfluidic-based electrochemical biochip for DNA hybridization detection. Following ssDNA probe functionalization, the specificity, sensitivity, and detection limit are studied with complementary and non-complementary ssDNA targets. Results illustrate the influence of the DNA hybridization events on the electrochemical system, with a detection limit of 3.8 nM.

微流体为基础的电化学生物芯片的无标记的DNA杂交分析

Miniaturization of analytical benchtop procedures into the micro-scale provides significant advantages in regards to reaction time, cost, and integration ...

Aqueous Droplets Used as Enzymatic Microreactors and Their Electromagnetic Actuation

For the successful implementation of microfluidic reaction systems, such as PCR and electrophoresis, the movement of small liquid volumes is essential. In conventional lab-on-a-chip-platforms, solvents and samples are passed through defined microfluidic channels with complex flow control installations. The droplet actuation platform presented here is a promising alternative. With it, it is possible to move a liquid drop (microreactor) on a planar surface of a reaction platform (lab-in-a-drop). The actuation of microreactors on the hydrophobic surface of the platform is based on the use of magnetic forces acting on the outer shell of the liquid drops which is made of a thin layer of superhydrophobic magnetite particles. The hydrophobic surface of the platform is needed to avoid any contact between the liquid core and the surface to allow a smooth movement of the microreactor. On the platform, one or more microreactors with volumes of 10 &#181;L can be positioned and moved simultaneously. The platform itself consists of a 3 x 3 matrix of electrical double coils which accommodate either neodymium or iron cores. The magnetic field gradients are automatically controlled. By variation of the magnetic field gradients, the microreactors' magnetic hydrophobic shell can be manipulated automatically to move the microreactor or open the shell reversibly. Reactions of substrates and corresponding enzymes can be initiated by merging the microreactors or bringing them into contact with surface immobilized catalysts.

Lab-in-a-drop reaction systems allow the versatile implementation of complex reactions in a microfluidic scale. An automated actuation platform consisting of a 3 x 3 matrix of electromagnetic coils was developed and successfully used to merge two 10 &#181;L microreactors and thereby initiate an enzymatic reaction in the resulting liquid marbles.

用作酶反应器的水滴及其电磁驱动

For the successful implementation of microfluidic reaction systems, such as PCR and electrophoresis, the movement of small liquid volumes is essential. In ...

Additive Manufacturing-Enabled Low-Cost Particle Detector

As particles with a size of 1 &#181;m or smaller pose a severe health risk to the human body, the detection and regulation of particle emissions are of great importance. A large share of particulate emissions are emitted by the transport sector. Most of the commercially available particle detectors are bulky, very expensive, and need additional equipment. This paper presents a protocol to build and test a standalone particle detector that is small and cost-efficient. 
The focus of this paper lies in the description of the detailed construction manual with video and the sensor evaluation procedure. The computer-aided design model of the sensor is included in the supplemental material. The manual explains all the construction steps, from 3D printing to the fully operational sensor. The sensor can detect charged particles and is therefore suitable for a wide range of applications. A possible field of application would be soot detection from power plants, wildfires, industries, and automobiles.

Here, we present a protocol on how to build and test a simple but efficient low-cost particle detector.

支持增材制造的低成本粒子探测器

As particles with a size of 1 &#181;m or smaller pose a severe health risk to the human body, the detection and regulation of particle emissions are of ...

A Performance-testing Platform for a Conduction Micropump with an FR-4 Copper-clad Electrode Plate

Here, a conduction micropump with symmetric planar electrode pairs prepared on flame-retardant glass-reinforced epoxy (FR-4) copper-clad laminate (CCL) is fabricated. It is used to investigate the influence of chamber dimensions on the performance of a conduction micropump and to determine the reliability of the conduction pump when acetone is used as the working fluid. A testing platform is set up to evaluate conduction micropump performance under different conditions. When the chamber height is 0.2 mm, the pump pressure reaches its peak value.

This paper presents a protocol for the fabrication of a conduction micropump using symmetric planar electrodes on flame-retardant glass-reinforced epoxy (FR-4) copper-clad laminate (CCL) to test the influence of chamber dimensions on the performance of a conduction micropump.

FR-4 铜包电极板导电微泵性能测试平台

Here, a conduction micropump with symmetric planar electrode pairs prepared on flame-retardant glass-reinforced epoxy (FR-4) copper-clad laminate (CCL) is ...

Dry Film Photoresist-based Electrochemical Microfluidic Biosensor Platform: Device Fabrication, On-chip Assay Preparation, and System Operation

In recent years, biomarker diagnostics became an indispensable tool for the diagnosis of human disease, especially for the point-of-care diagnostics. An easy-to-use and low-cost sensor platform is highly desired to measure various types of analytes (e.g., biomarkers, hormones, and drugs) quantitatively and specifically. For this reason, dry film photoresist technology - enabling cheap, facile, and high-throughput fabrication - was used to manufacture the microfluidic biosensor presented here. Depending on the bioassay used afterwards, the versatile platform is capable of detecting various types of biomolecules. For the fabrication of the device, platinum electrodes are structured on a flexible polyimide (PI) foil in the only clean-room process step. The PI foil serves as a substrate for the electrodes, which are insulated with an epoxy-based photoresist. The microfluidic channel is subsequently generated by the development and lamination of dry film photoresist (DFR) foils onto the PI wafer. By using a hydrophobic stopping barrier in the channel, the channel is separated into two specific areas: an immobilization section for the enzyme-linked assay and an electrochemical measurement cell for the amperometric signal readout.
The on-chip bioassay immobilization is performed by the adsorption of the biomolecules to the channel surface. The glucose oxidase enzyme is used as a transducer for electrochemical signal generation. In the presence of the substrate, glucose, hydrogen peroxide is produced, which is detected at the platinum working electrode. The stop-flow technique is applied to obtain signal amplification along with rapid detection. Different biomolecules can quantitatively be measured by means of the introduced microfluidic system, giving an indication of different types of diseases, or, in regard to therapeutic drug monitoring, facilitating a personalized therapy.

A microfluidic biosensor platform was designed and fabricated using low-cost dry film photoresist technology for the rapid and sensitive quantification of various analytes. This single-use system allows for the electrochemical readout of on-chip-immobilized enzyme-linked assays by means of the stop-flow technique.

干膜 Photoresist-based 电化学微流控生物传感器平台: 器件制备、片上检测制备及系统运行

In recent years, biomarker diagnostics became an indispensable tool for the diagnosis of human disease, especially for the point-of-care diagnostics. An ...