Name: solvent bonding for fabrication of pmma and cop microfluidic devices
Uploaded: 2017-01-17T15:00:00.000+00:00
Duration: 4 min 54 s
Description: Watch this Scientific Journal Video about Solvent Bonding for Fabrication of PMMA and COP Microfluidic Devices at JoVE.com

我们承认从加拿大自然科学和（NSERC，＃436117-2013）工程研究理事会，癌症研究学会（CRS，＃20172），骨髓瘤加拿大和大挑战加拿大的资金支持。

注意，以下所有描述的步骤已被开发，并在非洁净室环境中进行。溶剂粘接的步骤当然可以在洁净室中进行，如果有的话，但是这不是必需的。 1.热塑性微流体器件层的制备<ol><li>设计和选择的热塑性制造微流体装置的层，使用适当的制造方法（ 例如 ，微细铣削15，压花16 - 18，注射成型）。 </li><li>目测设备层，以确保边缘"干净"（ 即 ，无论从制造工艺毛刺或边角料的脊）。为获得最佳效果，检查在光学显微镜下，除了该装置的外边缘都加工微特征的边缘。 </li><li>如果目视检查过程中发现边角料，用刀片或手术刀小心删除任何垫erial防止器件层从平面对躺在彼此，使得这些层的界面进入共形接触。 </li><li>清洁设备与实验室肥皂和水，并用压缩空气干燥的表面。在2-丙醇2分钟淹没器件层并用压缩空气干燥。 </li></ol> 2.溶剂粘接<ol><li> 准备热压机（用于PMMA）或电炉（用于COP）。 <ol><li>对于PMMA（压克力浇铸的〜100-110℃的玻璃化转变温度）18预热按70°C，并允许温度稳定。 </li><li>对于COP（102℃的玻璃化转变温度，从制造商），烤盘预热至25℃，并允许温度稳定。 </li></ol></li><li> 准备粘接工艺溶剂。 <ol><li>对于聚甲基丙烯酸甲酯，测量加入0.5ml每接合面积的平方英寸乙醇。 </li><li>对于COP，准备2-丙醇和环己烷，机智的混合65:35为0.5ml每接合面积的平方英寸的混合物的公顷总体积。 注:对于COP，用玻璃吸管和容器，如环己烷会溶解通用聚丙烯实验器具。执行在通风橱所有混合和键合，如环己烷是有毒的。 </li></ol></li><li> 分配0.1毫升每清洗塑料层之间的粘结面积的平方英寸溶剂，并把这些层一起。目视检查在粘合界面的气泡，这是常见的，并且应该尽可能除去。 注:有利于迅速开展工作，一旦溶剂已被分配，如挥发性溶剂将开始蒸发（因此，溶剂混合物将在成分改变）。 <ol><li>如果存在气泡，滑动沿键合界面的两个塑料层，使它们几乎散开（但保持接触），然后滑动回在一起。 </li></ol></li><li> 对准装置的层用定位销，一个自定义的夹具，或者干脆用手（详情见讨论部分）。 <ol><li>如果使用对准销，对齐的销孔，并插入销插入设备栈。 </li><li>如果使用自定义的夹具，将设备堆栈到工具和设备周围拧紧。 </li><li>如果用手工对准，可使用手指来对齐设备的外边缘。 </li></ol></li><li> 将带有溶剂器件进入预加热机（用于PMMA），或放在预热烤盘（对于COP）。 <ol><li>对于聚甲基丙烯酸甲酯，施加的压力2300千帕为2分钟。 </li><li>对于COP，应用压力为350kPa。增加从25℃至70℃的温度以5℃/分钟的速率。达到70℃（后9分钟），债券另外的15分钟后</li></ol></li><li>使用镊子安全地移除热设备进行检查。结合现已完成。 </li><li> 在设备中删除任何剩余的液体（微通道或其他featurES）。 <ol><li>对于PMMA，请用压缩空气任何剩余的液体。对于COP，放在烤盘，烤绑定的设备在45℃24小时，以消除任何剩余的环己烷。 </li></ol></li></ol>

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作者宣称，他们没有竞争的经济利益。

潜在的结合策略的可行性取决于可用的设备。虽然电磁炉是比较普遍和自由重量可以廉价购买，高压策略，将需要使用热压机的。例如，我们的最佳结合PMMA配方需要高压用乙醇（ 见表1）键，所需要的压力是无法达到使用自由重量典型的设备尺寸。因此，如果只有一个加热板和重量都可用，PMMA可以代替使用不同的溶剂（在水中75％丙酮）接合。另外，使用需要一个通风柜还可能限制?...

微流体已经出现在过去的二十年，以及适合在微尺度1学习化学和物理，以及不断增长的承诺生物学研究2显著贡献技术- 4。大多数微流体装置的历来由聚（二甲基硅氧烷）制成（PDMS），硅氧烷弹性体，很容易使用，价格便宜，并提供了高品质的特性复制5。然而，PDMS已充分证明的缺点，并与大批量制造不相容处理6,7，因此，出现了对制造，因为它们的大规模生产，因此商业化潜力的热塑性材料的微流体装置，不断增长的趋势。 一来更广泛地采用塑料微细加工的主要障碍已经实现塑料器件的方便，高品质的结合。目前的战略运用Ťhermal，粘合剂和溶剂的结合技术，但许多患有显著挑战。热粘接增加自发荧光8和经常变形的微通道的几何形状9 - 11，而粘合剂技术需要模具，仔细对准，并最终离开暴露于微通道10中的粘合剂的厚度。溶剂粘接是有吸引力的，由于它的简单性，可调性，成本低10,12 - 14。尤其是，它的可调性使得优化各种塑料，它可以产生一致的，高质量接合，最大限度地减少微特征14的变形。 期间溶剂粘合，溶剂暴露增加聚合物链的塑料，这使得横跨接合界面链的相互扩散的表面附近的流动性。这使得通过扩散链的机械联锁纠缠，并导致AP物质环境的债券10。热粘接工作在类似的方式，但单独依赖于升高的温度下，以增加链移动性。因此，热的方法需要的温度附近或该聚合物的玻璃化转变温度以上，而使用溶剂可显著减少所需用于粘结的温度，从而降低不必要的变形。 我们提供贴合PMMA和COP设备的特定协议。然而，该协议和方法描述了热塑性微流体装置的溶剂粘合，可以为其它塑料材料，溶剂和可用的设备进行定制的简单，通用的方法。我们描述了评估质量保证金多种方法（ 例如 ，债券保险，粘结强度，粘结耐久性和微特征几何变形），并提供解决这些共同的挑战排除故障的方法。

<table><tbody><tr><td>COP</td><td>Zeonor</td><td>604Z1020R080</td><td>20 kg COP Pellets - 1020R. Multiple suppliers can be used, but may affect bonding characteristics.</td></tr><tr><td>PMMA</td><td>McMaster Carr</td><td>8560K173</td><td>1.5 mm sheet thickness for our typical applications. Multiple suppliers can be used, but may affect bonding characteristics.</td></tr><tr><td>Cyclohexane</td><td>Sigma-Aldrich</td><td>227048</td><td>Cyclohexane, anhydrous, 99.5%. Multiple suppliers can be used. Toxic, requires fumehood.</td></tr><tr><td>Ethanol</td><td>Sigma-Aldrich</td><td>24102</td><td>Ethanol, absolute, &amp;ge;99.8% (GC). Multiple suppliers can be used.</td></tr><tr><td>Acetone</td><td>Sigma-Aldrich</td><td>179124</td><td>Acetone, ACS reagent, &amp;ge;99.5%. Multiple suppliers can be used.</td></tr><tr><td>2-Propanol</td><td>Sigma-Aldrich</td><td>278475</td><td>2-Propanol, anhydrous, 99.5%. Multiple suppliers can be used.</td></tr><tr><td>Hot plate(s)</td><td>Torrey Pines Scientific</td><td>HP60</td><td>Fully programmable digital hotplate. Multiple suppliers can be used.</td></tr><tr><td>Free weights</td><td>Cap Barbell</td><td>RPG#2</td><td>Standard cast iron plate. Multiple suppliers and different weights can be used.</td></tr><tr><td>Heated press</td><td>Carver</td><td>Auto CH</td><td>Auto series heated hydraulic press. Multiple suppliers can be used. A press that fits in a fumehood would allow the most flexibility (this model does not).</td></tr><tr><td>CNC Milling Machine</td><td>Tormach</td><td>PCNC 770</td><td>3 Axis CNC mill. Multiple suppliers can be used.</td></tr><tr><td>Endmills</td><td>Various</td><td>Various</td><td>Required sizes depend on designs. Multiple suppliers can be used.</td></tr></tbody></table>

solvent bonding for fabrication of pmma and cop microfluidic devices

热塑性微流体装置提供优于那些从硅氧烷弹性体作出了许多优点，但粘结程序必须为每个感兴趣的热塑性被开发。溶剂粘合是可用于从各种塑料制造设备的简单和通用的方法。在两个器件层之间添加适当的溶剂中结合，并且热和压力被施加到该装置，以促进粘合。通过使用溶剂，塑料，热和压力的适当组合，该设备可以具有高质量键被密封，其特征为具有高的粘结范围，粘合强度，光学透明度，随着时间的推移的耐用性，以及低变形或损坏微特征几何。我们描述了从两个流行的热塑性塑料，聚（甲基丙烯酸甲酯）（PMMA），以及环烯烃聚合物（COP），以及各种各样的方法制备来表征所得键的质量接合装置，和策略的程序到特鲁bleshoot低质量债券。这些方法可用于开发其他塑料溶剂体系新溶剂粘合协议。

一般溶剂粘合过程的示意图示于图1。评估债券质量最简单方法是目视检查覆盖债券，因为债券覆盖较差是无粘结胶区域很容易看到，并且表示弱粘接。这样的区域典型地是邻近自由边缘（ 例如 ，外围设备的，或者接近打开的端口或微通道），并且还可以经常出现周围的污物或灰尘的任何颗粒在粘合界面。由于弱粘结较差粘合覆盖在协议的开发阶段，?...

Watch this Scientific Journal Video about Solvent Bonding for Fabrication of PMMA and COP Microfluidic Devices at JoVE.com

Solvent Bonding for Fabrication of PMMA and COP Microfluidic Devices

溶剂粘接是制造高品质债券热塑性微流体装置的简单和通用的方法。我们描述了一种协议来实现在PMMA中强，光学透明的键和COP的微流体装置能够保护微特征的详细信息，通过压力，温度，适当的溶剂中，和装置的几何形状的恰当组合。

溶剂粘接的PMMA的制备和COP微流体装置

Thermoplastic microfluidic devices offer many advantages over those made from silicone elastomers, but bonding procedures must be developed for each ...

solvent-bonding-for-fabrication-of-pmma-and-cop-microfluidic-devices

Research

JoVE Journal

Engineering

16.2K 次观看.  University of Toronto. 溶剂粘接是制造高品质债券热塑性微流体装置的简单和通用的方法。我们描述了一种协议来实现在PMMA中强，光学透明的键和COP的微流体装置能够保护微特征的详细信息，通过压力，温度，适当的溶剂中，和装置的几何形状的恰当组合。 

视频: Solvent Bonding for Fabrication of PMMA and COP Microfluidic Devices

Non-plasma Bonding of PDMS for Inexpensive Fabrication of Microfluidic Devices

In this video, we demonstrate how to use the neuron microfluidic device without plasma bonding.  In some cases it may be desirable to reversibly bond devices to the Corning No. 1 cover glass.  This could be due, perhaps, to a plasma cleaner not being available.  In other instances, it may be desirable to remove the device from the glass after the culturing of neurons for certain types of microscopy or for immunostaining, though it is not necessary to remove the device for immunostaining since the neurons can be stained in the device.  Some researchers, however, still prefer to remove the device.  In this case, reversible bonding of the device to the cover glass makes that possible.  There are some disadvantages to non-plasma bonding of the devices in that not as tight of a seal is formed.  In some cases axons may grow under the grooves rather than through them.  Also, because the glass and PDMS are hydrophobic, liquids do not readily enter the device making it necessary at times to force media and other reagents into the device.  Liquids will enter the device via capillary action, but it takes significantly longer as compared to devices that have been plasma bonded.  The plasma cleaner creates temporary hydrophilic charges on the glass and device that facilitate the flow of liquids through the device after bonding within seconds.  For non-plasma bound devices, liquid flow through the devices takes several minutes.  It is also important to note that the devices to be used with non-plasma bonding need to be sterilized first, whereas plasma treated devices do not need to be sterilized prior to use because the plasma cleaner will sterilize them.

In this video we demonstrate how to use the neuron microfluidic device without plasma bonding.

PDMS微流体装置的廉价制造的非等离子键合

In this video, we demonstrate how to use the neuron microfluidic device without plasma bonding.  In some cases it may be desirable to reversibly bond ...

科研

生物学

Fabrication of the Thermoplastic Microfluidic Channels

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using polymer/nanoparticle composite microscale lysis and solid phase extraction columns. The recovered samples are concentrated, small volume samples that are PCRable, without any additional cleanup. Here, we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then, we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns. We demonstrate grafting and polymerization of a carbon nanotube/polymer composite column for bacterial cell lysis. We then show the lysis process followed by solid phase extraction of nucleic acids from the sample on chip using a silica/polymer composite column. The attached protocols contain detailed instructions on how to make both lysis and solid phase extraction columns.

Here we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns.

制备热塑性微流体通道

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using ...

Microfluidic Pneumatic Cages: A Novel Approach for In-chip Crystal Trapping, Manipulation and Controlled Chemical Treatment

The precise localization and controlled chemical treatment of structures on a surface are significant challenges for common laboratory technologies. Herein, we introduce a microfluidic-based technology, employing a double-layer microfluidic device, which can trap and localize in situ and ex situ synthesized structures on microfluidic channel surfaces. Crucially, we show how such a device can be used to conduct controlled chemical reactions onto on-chip trapped structures and we demonstrate how the synthetic pathway of a crystalline molecular material and its positioning inside a microfluidic channel can be precisely modified with this technology. This approach provides new opportunities for the controlled assembly of structures on surface and for their subsequent treatment.

Herein, we describe the fabrication and operation of a double-layer microfluidic system made of polydimethylsiloxane (PDMS). We demonstrate the potential of this device for trapping, directing the coordination pathway of a crystalline molecular material and controlling chemical reactions onto on-chip trapped structures.

微流控气动笼:在芯片水晶捕获，处理的新方法和控制化学处理

The precise localization and controlled chemical treatment of structures on a surface are significant challenges for common laboratory technologies. ...

化学

Creating Sub-50 Nm Nanofluidic Junctions in PDMS Microfluidic Chip via Self-Assembly Process of Colloidal Particles

Polydimethylsiloxane (PDMS) is the prevailing building material to make microfluidic devices due to its ease of molding and bonding as well as its transparency. Due to the softness of the PDMS material, however, it is challenging to use PDMS for building nanochannels. The channels tend to collapse easily during plasma bonding. In this paper, we present an evaporation-driven self-assembly method of silica colloidal nanoparticles to create nanofluidic junctions with sub-50 nm pores between two microchannels. The pore size as well as the surface charge of the nanofluidic junction is tunable simply by changing the colloidal silica bead size and surface functionalization outside of the assembled microfluidic device in a vial before the self-assembly process. Using the self-assembly of nanoparticles with a bead size of 300 nm, 500 nm, and 900 nm, it was possible to fabricate a porous membrane with a pore size of ~45 nm, ~75 nm and ~135 nm, respectively. Under electrical potential, this nanoporous membrane initiated ion concentration polarization (ICP) acting as a cation-selective membrane to concentrate DNA by ~1,700 times within 15 min. This non-lithographic nanofabrication process opens up a new opportunity to build a tunable nanofluidic junction for the study of nanoscale transport processes of ions and molecules inside a PDMS microfluidic chip.

We propose a simple self-assembly technique of silica colloidal nanoparticles to create a nanofluidic junction between two microchannels in polydimethylsiloxane (PDMS). Using this technique, a nanoporous bead membrane with a pore size down to ~45 nm was built inside a microchannel and applied to electrokinetic preconcentration of DNA samples.

通过胶体粒子自组装过程创建在PDMS微流控芯片分50纳米的纳米流体结

Polydimethylsiloxane (PDMS) is the prevailing building material to make microfluidic devices due to its ease of molding and bonding as well as its ...

工程学

Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Covalent Organic Frameworks (COFs) are a class of porous covalent materials which are frequently synthesized as unprocessable crystalline powders. The first COF was reported in 2005 with much effort centered on the establishment of new synthetic routes for its preparation. To date, most available synthetic methods for COF synthesis are based on bulk mixing under solvothermal conditions. Therefore, there is increasing interest in developing systematic protocols for COF synthesis that provide for fine control over reaction conditions and improve COF processability on surfaces, which is essential for their use in practical applications. Herein, we present a novel microfluidic-based method for COF synthesis where the reaction between two constituent building blocks, 1,3,5-benzenetricarbaldehyde (BTCA) and 1,3,5-tris(4-aminophenyl)benzene (TAPB), takes place under controlled diffusion conditions and at room temperature. Using such an approach yields sponge-like, crystalline fibers of a COF material, hereafter called MF-COF. The mechanical properties of MF-COF and the dynamic nature of the approach allow the continuous production of MF-COF fibers and their direct printing onto surfaces. The general method opens new potential applications requiring advanced printing of 2D or 3D COF structures on flexible or rigid surfaces.

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

We present a novel microfluidic-based method for synthesis of covalent organic frameworks (COFs). We demonstrate how this approach can be used to produce continuous COF fibers, and also 2D or 3D COF structures on surfaces.

基于微流体的共价有机骨架（COFs）的合成:用于连续生产COF纤维和直接印刷在表面上的工具

Covalent Organic Frameworks (COFs) are a class of porous covalent materials which are frequently synthesized as unprocessable crystalline powders. The ...

Fabrication of Refractive-index-matched Devices for Biomedical Microfluidics

The use of microfluidic devices has emerged as a defining tool for biomedical applications. When combined with modern microscopy techniques, these devices can be implemented as part of a robust platform capable of making simultaneous complementary measurements. The primary challenge created by the combination of these two techniques is the mismatch in refractive index between the materials traditionally used to make microfluidic devices and the aqueous solutions typically used in biomedicine. This mismatch can create optical artifacts near the channel or device edges. One solution is to reduce the refractive index of the material used to fabricate the device by using a fluorinated polymer such as MY133-V2000 whose refractive index is similar to that of water (n = 1.33). Here, the construction of a microfluidic device made out of MY133-V2000 using soft lithography techniques is demonstrated, using O2 plasma in conjunction with an acrylic holder to increase the adhesion between the MY133-V2000 fabricated device and the polydimethylsiloxane (PDMS) substrate. The device is then tested by incubating it filled with cell culture media for 24 h to demonstrate the ability of the device to maintain cell culture conditions during the course of a typical imaging experiment. Finally, quantitative phase microscopy (QPM) is used to measure the distribution of mass within the live adherent cells in the microchannel. This way, the increased precision, enabled by fabricating the device from a low index of refraction polymer such as MY133-V2000 in lieu of traditional soft lithography materials such as PDMS, is demonstrated. Overall, this approach for fabricating microfluidic devices can be readily integrated into existing soft lithography workflows in order to reduce optical artifacts and increase measurement precision.

This protocol describes the fabrication of microfluidic devices from MY133-V2000 to eliminate artifacts that often arise in microchannels due to the mismatching refractive indices between microchannel structures and an aqueous solution. This protocol uses an acrylic holder to compress the encapsulated device, improving adhesion both chemically and mechanically.

生物医学微流体折射率匹配器件的研制

The use of microfluidic devices has emerged as a defining tool for biomedical applications. When combined with modern microscopy techniques, these devices ...

Double Emulsion Generation Using a Polydimethylsiloxane (PDMS) Co-axial Flow Focus Device

Double emulsions are useful in a number of biological and industrial applications in which it is important to have an aqueous carrier fluid. This paper presents a polydimethylsiloxane (PDMS) microfluidic device capable of generating water/oil/water double emulsions using a coaxial flow focusing geometry that can be fabricated entirely using soft lithography. Similar to emulsion devices using glass capillaries, double emulsions can be formed in channels with uniform wettability and with dimensions much smaller than the channel sizes. Three dimensional flow focusing geometry is achieved by casting a pair of PDMS slabs using two layer soft lithography, then mating the slabs together in a clamshell configuration. Complementary locking features molded into the PDMS slabs enable the accurate registration of features on each of the slab surfaces. Device testing demonstrates formation of double emulsions from 14 &#181;m to 50 &#181;m in diameter while using large channels that are robust against fouling and clogging.

Double Emulsion Generation Using a Polydimethylsiloxane PDMS Co-axial Flow Focus Device

Microfluidic double emulsions generation typically involves devices with patterned wettability or custom-fabricated glass components. Here we describe the fabrication and testing of an all polydimethylsiloxane (PDMS) double emulsion generator that does not require surface treatment or complicated fabrication processes, and is capable of producing double emulsions down to 14 &#181;m.

复乳代使用聚二甲基硅氧烷（PDMS）同轴流量聚焦设备

Double emulsions are useful in a number of biological and industrial applications in which it is important to have an aqueous carrier fluid. This paper ...

生物工程

Window on a Microworld: Simple Microfluidic Systems for Studying Microbial Transport in Porous Media

Microbial growth and transport in porous media have important implications for the quality of groundwater and surface water, the recycling of nutrients in the environment, as well as directly for the transmission of pathogens to drinking water supplies. Natural porous media is composed of an intricate physical topology, varied surface chemistries, dynamic gradients of nutrients and electron acceptors, and a patchy distribution of microbes. These features vary substantially over a length scale of microns, making the results of macro-scale investigations of microbial transport difficult to interpret, and the validation of mechanistic models challenging. Here we demonstrate how simple microfluidic devices can be used to visualize microbial interactions with micro-structured habitats, to identify key processes influencing the observed phenomena, and to systematically validate predictive models. Simple, easy-to-use flow cells were constructed out of the transparent, biocompatible and oxygen-permeable material poly(dimethyl siloxane). Standard methods of photolithography were used to make micro-structured masters, and replica molding was used to cast micro-structured flow cells from the masters. The physical design of the flow cell chamber is adaptable to the experimental requirements: microchannels can vary from simple linear connections to complex topologies with feature sizes as small as 2 &mu;m. Our modular EcoChip flow cell array features dozens of identical chambers and flow control by a gravity-driven flow module. We demonstrate that through use of EcoChip devices, physical structures and pressure heads can be held constant or varied systematically while the influence of surface chemistry, fluid properties, or the characteristics of the microbial population is investigated. Through transport experiments using a non-pathogenic, green fluorescent protein-expressing Vibrio bacterial strain, we illustrate the importance of habitat structure, flow conditions, and inoculums size on fundamental transport phenomena, and with real-time particle-scale observations, demonstrate that microfluidics offer a compelling view of a hidden world.

Microfluidic devices can be used to visualize complex natural processes in real time and at the appropriate physical scales. We have developed a simple microfluidic device that mimics key features of natural porous media for studying growth and transport of bacteria in the subsurface.

窗口上的一个微观世界：简单的微流体系统为研究多孔介质中的微生物运输

Microbial growth and transport in porous media have important implications for the quality of groundwater and surface water, the recycling of nutrients in ...

Computer Numerical Control Micromilling of a Microfluidic Acrylic Device with a Staggered Restriction for Magnetic Nanoparticle-Based Immunoassays

Microfluidic systems have greatly improved immunoassay techniques. However, many microfabrication techniques require specialized, expensive, or complicated equipment, making fabrication costly and incompatible with mass production, which is one of the most important preconditions for point-of-care tests (POCT) to be adopted in low-resource settings. This work describes the fabrication process of an acrylic (polymethylmethacrylate, PMMA) device for nanoparticle-conjugated enzymatic immunoassay testing using the computer numerical control (CNC) micromilling technique. The functioning of the microfluidic device is shown by performing an immunoassay to detect a commercial antibody using lysozyme as a model antigen conjugated to 100 nm magnetic nanoparticles. This device integrates a physical staggered restriction of only 5 &#181;m in height, used to capture magnetic microparticles that make up a magnetic trap by placing an external magnet. In this way, the magnetic force on the immunosupport of conjugated nanoparticles is enough to capture them and resist flow drag. This microfluidic device is particularly suitable for low-cost mass production without the loss of precision for immunoassay performance.

Microfluidics is a powerful tool for the development of diagnostic tests. However, expensive equipment and materials, as well as laborious fabrication and handling techniques, are often required. Here, we detail the fabrication protocol of an acrylic microfluidic device for magnetic micro- and nanoparticle-based immunoassays in a low-cost and simple-to-use setting.

基于磁性纳米颗粒免疫分析的交错限制微流控亚克力装置的计算机数控微铣削

Microfluidic systems have greatly improved immunoassay techniques. However, many microfabrication techniques require specialized, expensive, or ...

Rapid Fabrication of Custom Microfluidic Devices for Research and Educational Applications

Microfluidic devices allow for the manipulation of fluids, particles, cells, micro-sized organs or organisms in channels ranging from the nano to submillimeter scales. A rapid increase in the use of this technology in the biological sciences has prompted a need for methods that are accessible to a wide range of research groups. Current fabrication standards, such as PDMS bonding, require expensive and time consuming lithographic and bonding techniques. A viable alternative is the use of equipment and materials that are easily affordable, require minimal expertise and allow for the rapid iteration of designs. In this work we describe a protocol for designing and producing PET-laminates (PETLs), microfluidic devices that are inexpensive, easy to fabricate, and consume significantly less time to generate than other approaches to microfluidics technology. They consist of thermally bonded film sheets, in which channels and other features are defined using a craft cutter. PETLs solve field-specific technical challenges while dramatically reducing obstacles to adoption. This approach facilitates the accessibility of microfluidics devices in both research and educational settings, providing a reliable platform for new methods of inquiry.

Here we present a protocol to design and fabricate custom microfluidic devices with minimal financial and time investment. The aim is to facilitate the adoption of microfluidic technologies in biomedical research laboratories and educational settings.