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

Environmentally-controlled Microtensile Testing of Mechanically-adaptive Polymer Nanocomposites for ex vivo Characterization

Implantable microdevices are gaining significant attention for several biomedical applications1-4. Such devices have been made from a range of materials, each offering its own advantages and shortcomings5,6. Most prominently, due to the microscale device dimensions, a high modulus is required to facilitate implantation into living tissue. Conversely, the stiffness of the device should match the surrounding tissue to minimize induced local strain7-9. Therefore, we recently developed a new class of bio-inspired materials to meet these requirements by responding to environmental stimuli with a change in mechanical properties10-14. Specifically, our poly(vinyl acetate)-based nanocomposite (PVAc-NC) displays a reduction in stiffness when exposed to water and elevated temperatures (e.g. body temperature). Unfortunately, few methods exist to quantify the stiffness of materials in vivo15, and mechanical testing outside of the physiological environment often requires large samples inappropriate for implantation. Further, stimuli-responsive materials may quickly recover their initial stiffness after explantation. Therefore, we have developed a method by which the mechanical properties of implanted microsamples can be measured ex vivo, with simulated physiological conditions maintained using moisture and temperature control13,16,17. 
To this end, a custom microtensile tester was designed to accommodate microscale samples13,17 with widely-varying Young's moduli (range of 10 MPa to 5 GPa). As our interests are in the application of PVAc-NC as a biologically-adaptable neural probe substrate, a tool capable of mechanical characterization of samples at the microscale was necessary. This tool was adapted to provide humidity and temperature control, which minimized sample drying and cooling17. As a result, the mechanical characteristics of the explanted sample closely reflect those of the sample just prior to explantation.
The overall goal of this method is to quantitatively assess the in vivo mechanical properties, specifically the Young's modulus, of stimuli-responsive, mechanically-adaptive polymer-based materials. This is accomplished by first establishing the environmental conditions that will minimize a change in sample mechanical properties after explantation without contributing to a reduction in stiffness independent of that resulting from implantation. Samples are then prepared for implantation, handling, and testing (Figure 1A). Each sample is implanted into the cerebral cortex of rats, which is represented here as an explanted rat brain, for a specified duration (Figure 1B). At this point, the sample is explanted and immediately loaded into the microtensile tester, and then subjected to tensile testing (Figure 1C). Subsequent data analysis provides insight into the mechanical behavior of these innovative materials in the environment of the cerebral cortex.

Environmentally-controlled Microtensile Testing of Mechanically-adaptive Polymer Nanocomposites for ex vivo Characterization

A method is discussed by which the in vivo mechanical behavior of stimuli-responsive materials is monitored as a function of time. Samples are tested ex vivo using a microtensile tester with environmental controls to simulate the physiological environment. This work further promotes understanding the in vivo behavior of our material.

機械的に適応型ポリマーナノコンポジットの環境制御のMicrotensileテスト<em&gt; ex vivoで</em&gt;キャラ

Implantable microdevices are gaining significant attention for several biomedical applications1-4. Such devices have been made from a range of materials, ...

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 ...

Investigating Receptor-ligand Systems of the Cellulosome with AFM-based Single-molecule Force Spectroscopy

Cellulosomes are discrete multienzyme complexes used by a subset of anaerobic bacteria and fungi to digest lignocellulosic substrates. Assembly of the enzymes onto the noncatalytic scaffold protein is directed by interactions among a family of related receptor-ligand pairs comprising interacting cohesin and dockerin modules. The extremely strong binding between cohesin and dockerin modules results in dissociation constants in the low picomolar to nanomolar range, which may hamper accurate off-rate measurements with conventional bulk methods. Single-molecule force spectroscopy (SMFS) with the atomic force microscope measures the response of individual biomolecules to force, and in contrast to other single-molecule manipulation methods (i.e.&#160;optical tweezers), is optimal for studying high-affinity receptor-ligand interactions because of its ability to probe the high-force regime (&#62;120 pN). Here we present our complete protocol for studying cellulosomal protein assemblies at the single-molecule level. Using a protein topology derived from the native cellulosome, we worked with enzyme-dockerin and carbohydrate binding module-cohesin (CBM-cohesin) fusion proteins, each with an accessible free thiol group at an engineered cysteine residue. We present our site-specific surface immobilization protocol, along with our measurement and data analysis procedure for obtaining detailed binding parameters for the high-affinity complex. We demonstrate how to quantify single subdomain unfolding forces, complex rupture forces, kinetic off-rates, and potential widths of the binding well. The successful application of these methods in characterizing the cohesin-dockerin interaction responsible for assembly of multidomain cellulolytic complexes is further described.

Cellulosomes are multienzyme complexes designed for digesting cellulose. AFM-based SMFS was used to study the mechanical properties and folding configuration of cellulosome-associated protein assemblies. We present a complete workflow for protein immobilization, data acquisition, and data analysis to study the interactions of individual receptor-ligand complexes involved in cellulosome assembly.

Cellulosomes are discrete multienzyme complexes used by a subset of anaerobic bacteria and fungi to digest lignocellulosic substrates. Assembly of the ...

Cell Squeezing as a Robust, Microfluidic Intracellular Delivery Platform

Rapid mechanical deformation of cells has emerged as a promising, vector-free method for intracellular delivery of macromolecules and nanomaterials. This technology has shown potential in addressing previously challenging applications; including, delivery to primary immune cells, cell reprogramming, carbon nanotube, and quantum dot delivery. This vector-free microfluidic platform relies on mechanical disruption of the cell membrane to facilitate cytosolic delivery of the target material. Herein, we describe the detailed method of use for these microfluidic devices including, device assembly, cell preparation, and system operation. This delivery approach requires a brief optimization of device type and operating conditions for previously unreported applications. The provided instructions are generalizable to most cell types and delivery materials as this system does not require specialized buffers or chemical modification/conjugation steps. This work also provides recommendations on how to improve device performance and trouble-shoot potential issues related to clogging, low delivery efficiencies, and cell viability.

Rapid mechanical deformation of cells has emerged as a promising, vector-free method for intracellular delivery of macromolecules and nanomaterials. This protocol provides detailed steps on how to use the system for a broad range of applications.

堅牢、マイクロ流体細胞内送達プラットフォームとしての細胞絞る

Rapid mechanical deformation of cells has emerged as a promising, vector-free method for intracellular delivery of macromolecules and nanomaterials. This ...

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. ...

Three-Dimensionally Printed Microfluidic Cross-flow System for Ultrafiltration/Nanofiltration Membrane Performance Testing

Minimization and management of membrane fouling is a formidable challenge in diverse industrial processes and other practices that utilize membrane technology. Understanding the fouling process could lead to optimization and higher efficiency of membrane based filtration. Here we show the design and fabrication of an automated three-dimensionally (3-D) printed microfluidic cross-flow filtration system that can test up to 4 membranes in parallel. The microfluidic cells were printed using multi-material photopolymer 3-D printing technology, which used a transparent hard polymer for the microfluidic cell body and incorporated a thin rubber-like polymer layer, which prevents leakages during operation. The performance of ultrafiltration (UF), and nanofiltration (NF) membranes were tested and membrane fouling could be observed with a model foulant bovine serum albumin (BSA). Feed solutions containing BSA showed flux decline of the membrane. This protocol may be extended to measure fouling or biofouling with many other organic, inorganic or microbial containing solutions. The microfluidic design is especially advantageous for testing materials that are costly or only available in small quantities, for example polysaccharides, proteins, or lipids due to the small surface area of the membrane being tested. This modular system may also be easily expanded for high throughput testing of membranes.&#160;

Design and fabrication of a three-dimensionally (3-D) printed microfluidic cross-flow filtration system is demonstrated. The system is used to test performance and observe fouling of ultrafiltration and nanofiltration (thin film composite) membranes.

限外濾過/ナノ濾過膜性能試験のための三次元プリントマイクロ流体クロスフローシステム

Minimization and management of membrane fouling is a formidable challenge in diverse industrial processes and other practices that utilize membrane ...

Microfluidic Platform with Multiplexed Electronic Detection for Spatial Tracking of Particles

Microfluidic processing of biological samples typically involves differential manipulations of suspended particles under various force fields in order to spatially fractionate the sample based on a biological property of interest. For the resultant spatial distribution to be used as the assay readout, microfluidic devices are often subjected to microscopic analysis requiring complex instrumentation with higher cost and reduced portability. To address this limitation, we have developed an integrated electronic sensing technology for multiplexed detection of particles at different locations on a microfluidic chip. Our technology, called Microfluidic CODES, combines Resistive Pulse Sensing with Code Division Multiple Access to compress 2D spatial information into a 1D electrical signal. In this paper, we present a practical demonstration of the Microfluidic CODES technology to detect and size cultured cancer cells distributed over multiple microfluidic channels. As validated by the high-speed microscopy, our technology can accurately analyze dense cell populations all electronically without the need for an external instrument. As such, the Microfluidic CODES can potentially enable low-cost integrated lab-on-a-chip devices that are well suited for the point-of-care testing of biological samples.

We demonstrate a microfluidic platform with an integrated surface electrode network that combines resistive pulse sensing (RPS) with code division multiple access (CDMA), to multiplex detection and sizing of particles in multiple microfluidic channels.

粒子の空間追跡のための多重化された電子の検出とマイクロ流体プラットフォーム

Microfluidic processing of biological samples typically involves differential manipulations of suspended particles under various force fields in order to ...

An Ultrasonic Tool for Nerve Conduction Block in Diabetic Rat Models

Nerve conduction block with a high intensity-focused ultrasound (HIFU) transducer has been performed in normal and diabetic animal models recently. HIFU can reversibly block the conduction of peripheral nerves without damaging the nerves while using an appropriate ultrasonic parameter. Temporary and partial block of the action potentials of nerves shows that HIFU has the potential to be a useful clinical treatment for pain relief. This work demonstrates the procedures for suppressing the action potentials of neuropathic nerves in diabetic rats in vivo using an HIFU transducer. The first step is to generate adult male diabetic neuropathic rats by streptozotocin (STZ) injection. The second step is to evaluate the peripheral diabetic neuropathy in STZ-induced diabetic rats by an electronic von Frey probe and a hot plate. The final step is to record in vivo extracellular action potentials of the nerve exposed to HIFU sonication. The method showed here may benefit the study of ultrasound analgesic applications.

This work presents the methodology of applying high intensity-focused ultrasound to block the action potentials of diabetic neuropathic nerves.

糖尿病モデルラットにおける神経伝導の超音波ツール ブロックします。

Nerve conduction block with a high intensity-focused ultrasound (HIFU) transducer has been performed in normal and diabetic animal models recently. HIFU ...

A Microfluidic Platform for Longitudinal Imaging in Caenorhabditis elegans

In the last decade, microfluidic techniques have been applied to study small animals, including the nematode Caenorhabditis elegans, and have proved useful as a convenient live imaging platform providing capabilities for precise control of experimental conditions in real time. In this article, we demonstrate live imaging of individual worms employing WormSpa, a previously-published custom microfluidic device. In the device, multiple worms are individually confined to separate chambers, allowing multiplexed longitudinal surveillance of various biological processes. To illustrate the capability, we performed proof-of-principle experiments in which worms were infected in the device with pathogenic bacteria, and the dynamics of expression of immune response genes and egg laying were monitored continuously in individual animals. The simple design and operation of this device make it suitable for users with no previous experience with microfluidic-based experiments. We propose that this approach will be useful for many researchers interested in longitudinal observations of biological processes under well-defined conditions.

A Microfluidic Platform for Longitudinal Imaging in Caenorhabditis elegans

In this article, we demonstrate live imaging of individual worms employing a custom microfluidic device. In the device, multiple worms are individually confined to separate chambers, allowing multiplexed longitudinal surveillance of various biological processes.

カエノラブディティス ・ エレガンスにおける縦断的イメージングのためのマイクロ流体プラットフォーム

In the last decade, microfluidic techniques have been applied to study small animals, including the nematode Caenorhabditis elegans, and have proved ...

An Ultrahigh-throughput Microfluidic Platform for Single-cell Genome Sequencing

Sequencing technologies have undergone a paradigm shift from bulk to single-cell resolution in response to an evolving understanding of the role of cellular heterogeneity in biological systems. However, single-cell sequencing of large populations has been hampered by limitations in processing genomes for sequencing. In this paper, we describe a method for single-cell genome sequencing (SiC-seq) which uses droplet microfluidics to isolate, amplify, and barcode the genomes of single cells. Cell encapsulation in microgels allows the compartmentalized purification and tagmentation of DNA, while a microfluidic merger efficiently pairs each genome with a unique single-cell oligonucleotide barcode, allowing &gt;50,000 single cells to be sequenced per run. The sequencing data is demultiplexed by barcode, generating groups of reads originating from single cells. As a high-throughput and low-bias method of single-cell sequencing, SiC-seq will enable a broader range of genomic studies targeted at diverse cell populations.

Single-cell sequencing reveals genotypic heterogeneity in biological systems, but current technologies lack the throughput necessary for the deep profiling of community composition and function. Here, we describe a microfluidic workflow for sequencing &gt;50,000 single-cell genomes from diverse cell populations.

単一細胞のゲノムの配列のための超高スループット マイクロ流体プラットフォーム

Sequencing technologies have undergone a paradigm shift from bulk to single-cell resolution in response to an evolving understanding of the role of ...

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

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