この作品が主催した中国の国家自然科学基金 (51375176);(2014A030313264); 中国の広東地方の自然科学基金科学と技術 (2014B010126003) 中国広東省のプロジェクトを企画します。

警告: 使用前に関連するすべての材料安全データ用紙 (MSDS) を参照してください。アセトンは引火性の高い、目や気道に炎症を引き起こすことができます。関与の電圧は数千ボルト;したがって、電気火花は、実験を行うときに期待されています。爆発を避けるために、火花から火風通しのよい部屋で実験を行う。
 1。 板・ ホルダー加工 注: この作品は、工場の生産ラインにより電極板とホルダーを作製します。。材料だけ本稿のすべてのパーツのパラメーターが複雑なプロセスによりご紹介いたします。
1.4 mm を使用して <ol><li>材料と電極板のサイズ <ol><li>作製電極プレート 35 μ m の銅薄膜と FR 4 CCL。電極板の詳細なパラメーターの 図 1 を参照してください</li>。
	</ol></li> <li>電極のパラメーター <ol><li>工場から電極プレートを注文します。詳細については、 図 2 を参照してください</li>。
	</ol></li> <li>電極板の検査 <ol><li>電極板の準備の後電子顕微鏡を使用して、任意の顕著な欠陥下 100 倍と 300 倍の電極を検査します。 図 3 に示すように、電極の表面に小さな欠陥が、短絡を引き起こすことに注意してください</li>。
		<li>検査測定電極幅と寸法精度が、要件を満たしているかどうかを決定する間隔と</li>。
		<li>電気短絡が発生するか電流計とプレートをテストします</li>。
	</ol></li> <li>商工会議所板の準備 <ol><li> 図 4 に示すように、いくつかのシリコン膜を電極板と同じサイズにカットします。高さの異なる室板に異なる厚みをもつシリコーン膜を選択します</li>。
		<li> 図 5 に示すように、チャンバーの穴をパンチする特別なパンチング ツールを使用します</li>。
	</ol></li> <li>ホルダーの処理 <ol><li>工場からホルダーを注文します。詳細なパラメーターを 図 6 に示します</li>。
	</ol></li> <li>カバー プレートの作製 <ol><li>ドリル 2 つ穴の掘削を使用してカバー プレートの上には入口と出口の管をインストールするマシンします。自分の位置とサイズの 図 7 を参照してください</li>。
	</ol></li></ol> 2。マイクロ ポンプのアセンブリ <ol><li>洗いのすべての板、ホルダー、入口と出口の管、実験で使用される他のツールにアセトンを使用します。ビーカー内これらのツールとプレートを入れて、その後どっぷり浸かるため十分な 99.5% アセトンを注ぐ。超音波洗浄機中ビーカーを置きます。超音波洗浄機をオンにし、タイマーを 5 分に設定</li>
	<li>カバー プレートの 2 つの穴に入口と出口のステンレス鋼チューブを挿入します</li>。
	<li>シリコン膜電極板上のチャンバ プレートを置き、カバー プレートでカバーします</li>。
	<li>スタックしカバー プレートを揃え、商工会議所の板と電極板の上から下へと一直線に並べられたプレートをホルダーに挿入します。
	<ol><li>使用、M5 ボルト ホルダー内部プレートを修正します。それぞれ 図 8 と 図 9 に示すように、爆発ビューおよび組み立てられたマイクロ ポンプの通常のビューを参照してください</li>。
		<li>ボルトを締め、プレートを一緒に押します 。
		注: チューブと商工会議所のプレートにキャビティ作動液の通路となります。弾性チャンバー プレートできますも液体が流出するを防ぐためにプレートの間のギャップを封印します。それぞれ爆発ビューと 図 8 と 図 9 に組み立てられたマイクロ ポンプの通常のビューを参照してください</li>。
	</ol></li> <li>4 mm の外径と内径 2 mm の入口と出口のステンレス チューブを接続する 2 つのポリウレタン ホースを使用します</li>。
	<li>は、電流計、500 V DC 電源とシリーズのマイクロ ポンプを接続します。1 を挿入、電流計と電源、マイクロがショートの場合、電流計を保護するために mA ヒューズ</li>。
	<li>中アセトン 20-30 mL を 50 mL のビーカーに取水ホースを挿入します 。
	注: 図 10 完成したプラットフォームを示しています</li>。
</ol> 3。実験手順 <ol><li><ol><li>を 実験前に準備作業 を、マイクロ ポンプを埋めるためにアセトンを注入するシリンダーを使用します。液体のレベルに達すると排水ホース後、すべてのバブルは、商工会議所から押し出されるまで中アセトン 10 mL を注入し続ける 。
		注: カバー プレートと電極板が透明ではないのでチャンバー内左任意の気泡を見ることはないです。泡を除去するのに役立ちますアセトンを継続的に注入するが、マイクロ ポンプ内部に気泡が残ってないことは保証できません。泡が液体の通過をブロックまたは回路をショート、電極を書き込むマイクロ ポンプ内部のミクロ爆発の原因しなることがあります。ポンプ操作における気泡の効果ではない、まだ完全クリアが起こす故障が何度も観察されている</li>。
		<li>は、アセトンの 20-30 mL をビーカーに注ぎ、ビーカー内取水ホースを置きます。アセトンはポンプに流れることができる、マイクロ ポンプ室に空気が吸い込まれるない液体のレベルが少なくとも 5 mm 入口より高いであることを確認します</li>。
	</ol></li> <li>静圧テスト <ol><li>ホースが直線と垂直に残ることができるので、小さなフレームに排水ホースを接続します。アウトレット ホースと一緒に液体レベルを測るための定規を置く</li>。
		<li>、マイクロ ポンプを電源に接続します</li>。
		<li>スイッチを押してテストを開始し、初期の液体レベルをマークします</li>。
		<li>液面が安定になると、記録時間、最終的な液体のレベル、および電流</li>。
		<li>液体のレベルと現在のすべての 10 を記録し続けます、マイクロ ポンプが故障するまで s</li>。
	</ol></li> <li>フロー速度試験 <ol><li>排水ホースから出てくる液体を収集するために大型のメスシリンダーを使用します。ビーカー内の液体のレベルと同じ高度のまま終わり、アウトレット ホースを固定してください</li>。
		<li>、マイクロ ポンプを電源に接続します</li>。
		<li>スイッチを押してテストを開始し、初期の液体レベルをマークします</li>。
		<li>液体が排水ホースから流れ始めると記録メスシリンダー内のアセトンの量ごとの 10 s。実験が進むにつれて、液体のレベルを維持するためにビーカーにアセトンを追加します</li>。
	</ol></li> <li>信頼性試験<ol><li>平均作業時間を使用してポンプの信頼性を評価します。フロー速度試験、静加圧試験中にポンプが故障する前に手術時間を記録します。実験中の各内訳の詳細な現象を記録し、その後の詳細な分析電極板表面を検査します</li>。
	</ol>
	</li>
</ol>

<ol>
	<li>Kazemi, P. Z., Selvaganapathy, P. R., Ching, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+micropillar+electrode+spacing+on+the+performance+of+electrohydrodynamic+micropumps.">Effect of micropillar electrode spacing on the performance of electrohydrodynamic micropumps.</a> J Electrostat. 68 (4), 376-383 (2010).</li><li>Kano, I., Nishina, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+electrode+arrangements+on+EHD+conduction+pumping.">Effect of electrode arrangements on EHD conduction pumping.</a> IEEE Trans Ind Appl. 49 (2), 679-684 (2013).</li><li>Laser, D. J., Santiago, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+micropumps.">A review of micropumps.</a> J Micromech Microeng. 14 (6), R35 (2004).</li><li>Fylladitakis, E. D., Theodoridis, M. P., Moronis, A. X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review+on+the+history,+research,+and+applications+of+electrohydrodynamics.">Review on the history, research, and applications of electrohydrodynamics.</a> IEEE Trans Plasma Sci. 42 (2), 358-375 (2014).</li><li>Yazdani, M., Seyed-Yagoobi, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Electrostatics Joint Conf. , (2009).</li><li>Gharraei, R., Esmaeilzadeh, E., Hemayatkhah, M., Danaeefar, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+investigation+of+electrohydrodynamic+conduction+pumping+of+various+liquids+film+using+flush+electrodes.">Experimental investigation of electrohydrodynamic conduction pumping of various liquids film using flush electrodes.</a> J Electrostat. 69 (1), 43-53 (2011).</li><li>Gharraei, R., Esmaeilzadeh, E., Nobari, M. R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Numerical+investigation+of+conduction+pumping+of+dielectric+liquid+film+using+flush-mounted+electrodes.">Numerical investigation of conduction pumping of dielectric liquid film using flush-mounted electrodes.</a> Theor Comp Fluid Dyn. 28 (1), 89 (2014).</li><li>Jeong, S. -. I., Seyed-Yagoobi, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+study+of+electrohydrodynamic+pumping+through+conduction+phenomenon.">Experimental study of electrohydrodynamic pumping through conduction phenomenon.</a> J Electrostat. 56 (2), 123-133 (2002).</li><li>Seyed-Yagoobi, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrohydrodynamic+pumping+of+dielectric+liquids.">Electrohydrodynamic pumping of dielectric liquids.</a> J Electrostat. 63 (6), 861-869 (2005).</li><li>Hojjati, M., Esmaeilzadeh, E., Sadri, B., Gharraei, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrohydrodynamic+conduction+pumps+with+cylindrical+electrodes+for+pumping+of+dielectric+liquid+film+in+an+open+channel.">Electrohydrodynamic conduction pumps with cylindrical electrodes for pumping of dielectric liquid film in an open channel.</a> Colloid Surface A. 392 (1), 294-299 (2011).</li><li>Yazdani, M., Seyed-Yagoobi, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Numerical+investigation+of+electrohydrodynamic-conduction+pumping+of+liquid+film+in+the+presence+of+evaporation.">Numerical investigation of electrohydrodynamic-conduction pumping of liquid film in the presence of evaporation.</a> J Heat Trans-T ASME. 131 (1), 011602 (2009).</li><li>Vafaie, R. H., Ghavifekr, H. B., Lintel, H., Brugger, J., Renaud, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bi-directional+AC+electrothermal+micropump+for+on-chip+biological+applications.">Bi-directional AC electrothermal micropump for on-chip biological applications.</a> Electrophoresis. 37 (5-6), 719-726 (2016).</li><li>Pearson, M. R., Seyed-Yagoobi, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+Study+of+Linear+and+Radial+Two-Phase+Heat+Transport+Devices+Driven+by+Electrohydrodynamic+Conduction+Pumping.">Experimental Study of Linear and Radial Two-Phase Heat Transport Devices Driven by Electrohydrodynamic Conduction Pumping.</a> J Heat Trans-T ASME. 137 (2), 022901 (2015).</li></ol>

著者が明らかに何もありません。

プロトコルの中で重要な手順の 1 つは電極板を慎重に検査します。電極の端に小さなバリが、短絡と表面性状がポンプ性能に大きく影響します。電極板ホルダーの清掃も非常に重要です。小さなダスト粒子があります作業の液体の流れをブロックし、短絡を引き起こすので、電極室高さは 1 ミリメートル未満のものです。テストの前に商工会議所にアセトンを注入、チャンバー外の泡を削除?...

マイクロ ポンプは、ほとんどのポンプよりもはるかに小さい規模で液体の流れをドライブできます。近年では、様々 な駆動方式はマイクロ流体システム1,2,3,4,5に正常に適用されます。電気流体力学的 (EHD) ポンプは、シンプルで簡単に6を組み立てそれをなる液体、すべての可動部品なしに直接力を発揮できます。料金の種類に応じて EHD ポンプは、噴射ポンプ、誘導ポンプまたは伝導ポンプに分類できます。噴射ポンプは、液体の導電率を変更しながら、等温液体誘導ポンプには働かない。このような問題がない、ため伝導ポンプより安定、広いアプリケーションがあります。
伝導ポンプは、液体分子の解離と再結合速度の不一致に基づいています。通常、解離と結合のプロセスは、7、8を次のように表現できます。 
<img alt="Equation" src="/files/ftp_upload/55867/55867eq1.jpg"> 組み換え率krは定数解離率kdは電界強度の関数。電界強度一定の値に達すると、分解速度は再結合速度を超えます。その後より多くの自由料金反対の極性と heterocharge 層のフォームの 2 つの電極への旅行します。これらの heterocharge 層は、電荷の運動をすすめる液体分子ポンプへの鍵です。したがって、非対称電極または正と負のイオン9,10、11,12 の移動性の不一致を使用してチャンバ内液体で純体力を生成できます。.
この作品は、伝導ポンプの対称平面電極板を製造する新しい方法を紹介します。FR 4 CCL に電極板を用意し、ポンプ室は、マイクロマシニングによって準備されます。製造プロセスはナノリソグラフィなど他の製法に比べて比較的簡単な。異なる条件下で伝導マイクロ ポンプの性能を調査するためのテスト ・ プラットフォームを設定します。さらに、異なる状況下で伝導マイクロ ポンプの信頼性の調査も。

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a performance-testing platform for a conduction micropump with an fr-4 copper-clad electrode plate

ここでは、難燃性ガラス繊維強化エポキシ樹脂 (FR 4) 銅張積層板 (CCL) 上に作製した対称平面電極対を持つ伝導マイクロ ポンプを作製しました。槽寸法の伝導マイクロ ポンプの性能に及ぼす影響を調査するため、作動流体としてアセトンを使用する場合、伝導ポンプの信頼性を判断するために使用されます。異なる条件下で伝導マイクロ ポンプの性能を評価するテストのプラットフォームを設定します。商工会議所の高さが 0.2 mm と、ポンプの圧力のピーク値に達する。

ポンプの圧力とその増加率の上昇、図 11のように、電圧を増加させるとき。1,100 がポンプの圧力に達すると電圧が 500 V に達したら、ペンシルバニア州
ポンプの静圧力は、ポンプ室の高さが商工会議所の高さが 0.2 mm 未満の増加と します。ポンプ性能チャンバ高さ 0.2 mm は、その最高点に達する。そ?...

Watch this Scientific Journal Video about A Performance-testing Platform for a Conduction Micropump with an FR-4 Copper-clad Electrode Plate at JoVE.com

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

槽寸法の性能への影響をテストする難燃性ガラス繊維強化エポキシ樹脂 (FR 4) 銅張積層板 (CCL) の対称平面電極を用いた伝導マイクロ ポンプの作製のためのプロトコルを提案する、伝導マイクロ。

パフォーマンス テスト用 FR 4 銅クラッド電極に伝導マイクロ ポンプ

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

a-performance-testing-platform-for-conduction-micropump-with-an-fr-4

Research

JoVE Journal

Bioengineering

5.9K ビュー.  South China University of Technology. 槽寸法の性能への影響をテストする難燃性ガラス繊維強化エポキシ樹脂 (FR 4) 銅張積層板 (CCL) の対称平面電極を用いた伝導マイクロ ポンプの作製のためのプロトコルを提案する、伝導マイクロ。

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

Hollow Microneedle-based Sensor for Multiplexed Transdermal Electrochemical Sensing

The development of a minimally invasive multiplexed monitoring system for rapid analysis of biologically-relevant molecules could offer individuals suffering from chronic medical conditions facile assessment of their immediate physiological state. Furthermore, it could serve as a research tool for analysis of complex, multifactorial medical conditions. In order for such a multianalyte sensor to be realized, it must be minimally invasive, sampling of interstitial fluid must occur without pain or harm to the user, and analysis must be rapid as well as selective.
Initially developed for pain-free drug delivery, microneedles have been used to deliver vaccines and pharmacologic agents (e.g., insulin) through the skin.1-2 Since these devices access the interstitial space, microneedles that are integrated with microelectrodes can be used as transdermal electrochemical sensors. Selective detection of glucose, glutamate, lactate, hydrogen peroxide, and ascorbic acid has been demonstrated using integrated microneedle-electrode devices with carbon fibers, modified carbon pastes, and platinum-coated polymer microneedles serving as transducing elements.3-7,8
This microneedle sensor technology has enabled a novel and sophisticated analytical approach for in situ and simultaneous detection of multiple analytes. Multiplexing offers the possibility of monitoring complex microenvironments, which are otherwise difficult to characterize in a rapid and minimally invasive manner. For example, this technology could be utilized for simultaneous monitoring of extracellular levels of, glucose, lactate and pH,9 which are important metabolic indicators of disease states7,10-14 (e.g., cancer proliferation) and exercise-induced acidosis.15

This article details the construction of a multiplexed microneedle-based sensor. The device is being developed for in situ sampling and electrochemical analysis of multiple analytes in a rapid and selective manner. We envision clinical medicine and biomedical research uses for these microneedle-based sensors.

多重経皮電気化学センシングのための中空マイクロニードルベースの​​センサ

The development of a minimally invasive multiplexed monitoring system for rapid analysis of biologically-relevant molecules could offer individuals ...

生物工学

A Versatile Automated Platform for Micro-scale Cell Stimulation Experiments

Study of cells in culture (in vitro analysis) has provided important insight into complex biological systems. Conventional methods and equipment for in vitro analysis are well suited to study of large numbers of cells (&ge;105) in milliliter-scale volumes (&ge;0.1 ml). However, there are many instances in which it is necessary or desirable to scale down culture size to reduce consumption of the cells of interest and/or reagents required for their culture, stimulation, or processing. Unfortunately, conventional approaches do not support precise and reproducible manipulation of micro-scale cultures, and the microfluidics-based automated systems currently available are too complex and specialized for routine use by most laboratories. To address this problem, we have developed a simple and versatile technology platform for automated culture, stimulation, and recovery of small populations of cells (100 - 2,000 cells) in micro-scale volumes (1 - 20 &mu;l). The platform consists of a set of fibronectin-coated microcapillaries ("cell perfusion chambers"), within which micro-scale cultures are established, maintained, and stimulated; a digital microfluidics (DMF) device outfitted with "transfer" microcapillaries ("central hub"), which routes cells and reagents to and from the perfusion chambers; a high-precision syringe pump, which powers transport of materials between the perfusion chambers and the central hub; and an electronic interface that provides control over transport of materials, which is coordinated and automated via pre-determined scripts. As an example, we used the platform to facilitate study of transcriptional responses elicited in immune cells upon challenge with bacteria. Use of the platform enabled us to reduce consumption of cells and reagents, minimize experiment-to-experiment variability, and re-direct hands-on labor. Given the advantages that it confers, as well as its accessibility and versatility, our platform should find use in a wide variety of laboratories and applications, and prove especially useful in facilitating analysis of cells and stimuli that are available in only limited quantities.

We have developed an automated cell culture and interrogation platform for micro-scale cell stimulation experiments. The platform offers simple, versatile, and precise control in cultivating and stimulating small populations of cells, and recovering lysates for molecular analyses. The platform is well suited to studies that use precious cells and/or reagents.

マイクロスケール細胞刺激のための実験のための多目的自動化プラットフォーム

Study of cells in culture (in vitro analysis) has provided important insight into complex biological systems. Conventional methods and equipment for in ...

High Throughput Microfluidic Rapid and Low Cost Prototyping Packaging Methods

In this work, 3 different packaging and assembly techniques are presented. They can be classified into two categories: one-time use and reusable packaging techniques.
The one-time use packaging technique employs UV-based and temperature curing epoxies to connect microtubes to access holes, wire-bonding for integrated circuit connections, and silver epoxy for electrical connections. This method is based on a robust assembly technique that can support relatively high pressure close to 1 psi and does not need any support to strengthen the microfluidic architecture.
Reusable packaging techniques consist of PDMS-based microtube interconnectors and anisotropic adhesive films for electrical connections. These devices are more sensitive and fragile. Consequently, Plexiglas support is added to the microfluidic structure to improve the electrical contact when anisotropic adhesive films are used, and also to strengthen the microfluidic architecture. In addition, a micromanipulator is needed to maintain tubes while using a thin PDMS layer to connect them to the access holes. Different PDMS layer thicknesses, ranging from 0.45-3 mm, are tested to compare the best adherence versus injection rates. Applied injection rates are varied from 50-300 &#956;l/hr for 0.45-3 mm PDMS layers, respectively. These techniques are mainly applicable for low-pressure applications. However, they can be extended for high-pressure ones through plasma-oxygen process to permanently seal the PDMS to glass substrates. The main advantage of this technique, besides the fact that it is reusable, consists of keeping the device observable when the microchannel length is very short (in the range of 3 mm or lower).

In this article we describe different techniques for microfluidic rapid prototyping platforms. The proposed techniques are based on ultraviolet (UV) sensitive and temperature curing epoxies, polydimethylsiloxane (PDMS) based tubing, wire-bonding, and anisotropic adhesive films. The assembling procedures presented are developed for both one-time use devices as well as reusable microfluidic systems.

ハイスループットマイクロ流体の迅速かつ低コストのプロトタイピング包装方法

In this work, 3 different packaging and assembly techniques are presented. They can be classified into two categories: one-time use and reusable packaging ...

A Microfluidic Platform for Precision Small-volume Sample Processing and Its Use to Size Separate Biological Particles with an Acoustic Microdevice

A major advantage of microfluidic devices is the ability to manipulate small sample volumes, thus reducing reagent waste and preserving precious sample. However, to achieve robust sample manipulation it is necessary to address device integration with the macroscale environment. To realize repeatable, sensitive particle separation with microfluidic devices, this protocol presents a complete automated and integrated microfluidic platform that enables precise processing of 0.15&#8211;1.5 ml samples using microfluidic devices. Important aspects of this system include modular device layout and robust fixtures resulting in reliable and flexible world to chip connections, and fully-automated fluid handling which accomplishes closed-loop sample collection, system cleaning and priming steps to ensure repeatable operation. Different microfluidic devices can be used interchangeably with this architecture. Here we incorporate an acoustofluidic device, detail its characterization, performance optimization, and demonstrate its use for size-separation of biological samples. By using real-time feedback during separation experiments, sample collection is optimized to conserve and concentrate sample. Although requiring the integration of multiple pieces of equipment, advantages of this architecture include the ability to process unknown samples with no additional system optimization, ease of device replacement, and precise, robust sample processing.

This protocol describes a system architecture for performing automated small volume (0.15&#8211;1.5 ml) particle separations using a microfluidic device, and discusses methods to optimize acoustofluidic device performance and operation.

マイクロ流体精密小容量サンプル処理のためのプラットフォームとアコースティックマイクロデバイスで区切り生物学的粒子サイズのためのその使用

A major advantage of microfluidic devices is the ability to manipulate small sample volumes, thus reducing reagent waste and preserving precious sample. ...

Fabrication and Characterization of Thickness Mode Piezoelectric Devices for Atomization and Acoustofluidics

We present a technique to fabricate simple thickness mode piezoelectric devices using lithium niobate (LN). Such devices have been shown to atomize liquid more efficiently, in terms of &#64258;ow rate per power input, than those that rely on Rayleigh waves and other modes of vibration in LN or lead zirconate titanate (PZT). The complete device is composed of a transducer, a transducer holder, and a &#64258;uid supply system. The fundamentals of acoustic liquid atomization are not well known, so techniques to characterize the devices and to study the phenomena are also described. Laser Doppler vibrometry (LDV) provides vibration information essential in comparing acoustic transducers and, in this case, indicates whether a device will perform well in thickness vibration. It can also be used to &#64257;nd the resonance frequency of the device, though this information is obtained more quickly via impedance analysis. Continuous &#64258;uid atomization, as an example application, requires careful &#64258;uid flow control, and we present such a method with high-speed imaging and droplet size distribution measurements via laser scattering.

Fabrication of piezoelectric thickness mode transducers via direct current sputtering of plate electrodes on lithium niobate is described. Additionally, reliable operation is achieved with a transducer holder and &#64258;uid supply system and characterization is demonstrated via impedance analysis, laser doppler vibrometry, high-speed imaging, and droplet size distribution using laser scattering.

微粒化およびアユースト流体のための厚さモード圧電デバイスの作製と特性

We present a technique to fabricate simple thickness mode piezoelectric devices using lithium niobate (LN). Such devices have been shown to atomize liquid ...

工学

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.

ドライ フィルムのレジストを用いた電気化学マイクロ流体バイオ プラットフォーム: デバイス作製、チップの試金の準備、およびシステム操作

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

Fabrication and Validation of an Organ-on-chip System with Integrated Electrodes to Directly Quantify Transendothelial Electrical Resistance

Organs-on-chips, in vitro models involving the culture of (human) tissues inside microfluidic devices, are rapidly emerging and promise to provide useful research tools for studying human health and disease. To characterize the barrier function of cell layers cultured inside organ-on-chip devices, often transendothelial or transepithelial electrical resistance (TEER) is measured. To this end, electrodes are usually integrated into the chip by micromachining methods to provide more stable measurements than is achieved with manual insertion of electrodes into the inlets of the chip. However, these electrodes frequently hamper visual inspection of the studied cell layer or require expensive cleanroom processes for fabrication. To overcome these limitations, the device described here contains four easily integrated electrodes that are placed and fixed outside of the culture area, making visual inspection possible. Using these four electrodes the resistance of six measurement paths can be quantified, from which the TEER can be directly isolated, independent of the resistance of culture medium-filled microchannels. The blood-brain barrier was replicated in this device and its TEER was monitored to show the device applicability. This chip, the integrated electrodes and the TEER determination method are generally applicable in organs-on-chips, both to mimic other organs or to be incorporated into existing organ-on-chip systems.

This publication describes the fabrication of an organ-on-chip device with integrated electrodes for direct quantification of transendothelial electrical resistance (TEER). For validation, the blood-brain barrier was mimicked inside this microfluidic device and its barrier function was monitored. The presented methods for electrode integration and direct TEER quantification are generally applicable.

作製と内皮下電気抵抗を直接定量化する統合型電極を用いたオンチップ器官システムの検証

Organs-on-chips, in vitro models involving the culture of (human) tissues inside microfluidic devices, are rapidly emerging and promise to provide useful ...

Mechano-Node-Pore Sensing: A Rapid, Label-Free Platform for Multi-Parameter Single-Cell Viscoelastic Measurements

Cellular mechanical properties are involved in a wide variety of biological processes and diseases, ranging from stem cell differentiation to cancer metastasis. Conventional methods for measuring these properties, such as atomic force microscopy (AFM) and micropipette aspiration (MA), capture rich information, reflecting a cell's full viscoelastic response; however, these methods are limited by very low throughput. High-throughput approaches, such as real-time deformability cytometry (RT-DC), can only measure limited mechanical information, as they are often restricted to single-parameter readouts that only reflect a cell's elastic properties. In contrast to these methods, mechano-node-pore sensing (mechano-NPS) is a flexible, label-free microfluidic platform that bridges the gap in achieving multi-parameter viscoelastic measurements of a cell with moderate throughput. A direct current (DC) measurement is used to monitor cells as they transit a microfluidic channel, tracking their size and velocity before, during, and after they are forced through a narrow constriction. This information (i.e., size and velocity) is used to quantify each cell's transverse deformation, resistance to deformation, and recovery from deformation. In general, this electronics-based microfluidic platform provides multiple viscoelastic cell properties, and thus a more complete picture of a cell's mechanical state. Because it requires minimal sample preparation, utilizes a straightforward electronic measurement (in contrast to a high-speed camera), and takes advantage of standard soft lithography fabrication, the implementation of this platform is simple, accessible, and adaptable to downstream analysis. This platform's flexibility, utility, and sensitivity have provided unique mechanical information on a diverse range of cells, with the potential for many more applications in basic science and clinical diagnostics.

Presented here is a method to mechanically phenotype single cells using an electronics-based microfluidic platform called mechano-node-pore sensing (mechano-NPS). This platform maintains moderate throughput of 1-10 cells/s while measuring both the elastic and viscous biophysical properties of cells.

メカノノードポアセンシング:マルチパラメータシングルセル粘弾性測定のための迅速でラベルフリーのプラットフォーム

Cellular mechanical properties are involved in a wide variety of biological processes and diseases, ranging from stem cell differentiation to cancer ...

振幅変調電気変形によるRBCの機械的疲労試験

Amplitude-Modulated Electrodeformation to Evaluate Mechanical Fatigue of Biological Cells

Red blood cells (RBCs) are known for their remarkable deformability. They repeatedly undergo considerable deformation when passing through the microcirculation. Reduced deformability is seen in physiologically aged RBCs. Existing techniques to measure cell deformability cannot easily be used for measuring fatigue, the gradual degradation in cell membranes caused by cyclic loads. We present a protocol to evaluate mechanical degradation in RBCs from cyclic shear stresses using amplitude shift keying (ASK) modulation-based electrodeformation in a microfluidic channel. Briefly, the interdigitated electrodes in the microfluidic channel are excited with a low voltage alternating current at radio frequencies using a signal generator. RBCs in suspension respond to the electric field and exhibit positive dielectrophoresis (DEP), which moves cells to the electrode edges. Cells are then stretched due to the electrical forces exerted on the two cell halves, resulting in uniaxial stretching, known as electrodeformation. The level of shear stress and the resultant deformation can be easily adjusted by changing the amplitude of the excitation wave. This enables quantifications of nonlinear deformability of RBCs in response to small and large deformations at high throughput. Modifying the excitation wave with the ASK strategy induces cyclic electrodeformation with programmable loading rates and frequencies. This provides a convenient way for the characterization of RBC fatigue. Our ASK-modulated electrodeformation approach enables, for the first time, a direct measurement of RBC fatigue from cyclic loads. It can be used as a tool for general biomechanical testing, for analyses of cell deformability and fatigue in other cell types and diseased conditions, and can also be combined with strategies to control the microenvironment of cells, such as oxygen tension and biological and chemical cues.

著者スポットライト:電気変形挙動の調節による循環細胞のバイオメカニクスの研究 

Presented here is a protocol for mechanical fatigue testing in the case of human red blood cells using an amplitude-modulated electrodeformation approach. This general approach can be used to measure the systematic changes in morphological and biomechanical characteristics of biological cells in a suspension from cyclic deformation.

パフォーマンステスト用 FR 4 銅クラッド電極に伝導マイクロポンプ

要約

さらに動画を探す

この動画の章

多重経皮電気化学センシングのための中空マイクロニードルベースのセンサ

マイクロスケール細胞刺激のための実験のための多目的自動化プラットフォーム

ハイスループットマイクロ流体の迅速かつ低コストのプロトタイピング包装方法

マイクロ流体精密小容量サンプル処理のためのプラットフォームとアコースティックマイクロデバイスで区切り生物学的粒子サイズのためのその使用

微粒化およびアユースト流体のための厚さモード圧電デバイスの作製と特性

ドライフィルムのレジストを用いた電気化学マイクロ流体バイオプラットフォーム: デバイス作製、チップの試金の準備、およびシステム操作

作製と内皮下電気抵抗を直接定量化する統合型電極を用いたオンチップ器官システムの検証

メカノノードポアセンシング:マルチパラメータシングルセル粘弾性測定のための迅速でラベルフリーのプラットフォーム

生体細胞の機械的疲労を評価するための振幅変調電極形成

生体細胞の機械的疲労を評価するための振幅変調電極形成

パフォーマンス テスト用 FR 4 銅クラッド電極に伝導マイクロ ポンプ

要約

さらに動画を探す

この動画の章

多重経皮電気化学センシングのための中空マイクロニードルベースの​​センサ

マイクロスケール細胞刺激のための実験のための多目的自動化プラットフォーム

ハイスループットマイクロ流体の迅速かつ低コストのプロトタイピング包装方法

マイクロ流体精密小容量サンプル処理のためのプラットフォームとアコースティックマイクロデバイスで区切り生物学的粒子サイズのためのその使用

微粒化およびアユースト流体のための厚さモード圧電デバイスの作製と特性

ドライ フィルムのレジストを用いた電気化学マイクロ流体バイオ プラットフォーム: デバイス作製、チップの試金の準備、およびシステム操作

作製と内皮下電気抵抗を直接定量化する統合型電極を用いたオンチップ器官システムの検証

メカノノードポアセンシング:マルチパラメータシングルセル粘弾性測定のための迅速でラベルフリーのプラットフォーム

生体細胞の機械的疲労を評価するための振幅変調電極形成

生体細胞の機械的疲労を評価するための振幅変調電極形成

パフォーマンステスト用 FR 4 銅クラッド電極に伝導マイクロポンプ

多重経皮電気化学センシングのための中空マイクロニードルベースのセンサ

ドライフィルムのレジストを用いた電気化学マイクロ流体バイオプラットフォーム: デバイス作製、チップの試金の準備、およびシステム操作