Name: stress-induced antibiotic susceptibility testing on a chip
Uploaded: 2014-01-08T13:00:00
Description: Watch this Scientific Journal Video about Stress-induced Antibiotic Susceptibility Testing on a Chip at JoVE.com

我们感谢弗劳恩霍夫制造创新中心的工程师和学生。感谢安德烈亚斯·普林森、霍尔格·维尔兹、道格·福斯、大卫·查金和苏东树博士在实验系统的设计、加工和自动化方面所做的帮助。我们感谢朱莉娅·库卡茨、梅兰妮·齐默尔曼、尼科·克雷茨马尔、蒂姆·甘贝尔、乔希·维拉努埃瓦、米诺里·希米祖和卡塔日娜·库利加在测试实验协议和数据收集方面提供帮助。我们感谢哈佛大学和麻省理工学院广泛研究所成像平台的安妮·卡彭特博士和马克-安东尼·布雷博士帮助开发CellProfiler的图像分析程序。国家过敏和传染病研究所的R21AI079474和1R01AI101446部分支持了该项目。内容完全由作者负责，不一定代表国家过敏和传染病研究所或国家卫生研究院的官方观点。该项目也得到了美国弗劳恩霍夫的支持。

1. 制作 PDMS 层（图 1）
<ol><li>以10：1的比例大力混合PDMS和固化剂。为了去除气泡，在室温下将粘稠的混合物在真空室中分解1小时。</li>
	<li>在秤上，将 PDMS 缓慢地倒在铝模具上。从中心倒入，保持模具水平。请务必将引脚揭开。一旦达到目标重量，停止浇注。 我们的模具需要 4 克 PDMS 和 0.4 克固化试剂。
</li>
	<li>将模具放在烤箱内，并在 37 °C 的夜间固化。 替代固化时间为 2 小时?...

<ol>
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J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bacterial+viability+and+antibiotic+susceptibility+testing+with+SYTOX+green+nucleic+acid+stain.">Bacterial viability and antibiotic susceptibility testing with SYTOX green nucleic acid stain.</a> Appl. Environ. Microbiol. 63, 2421-2431 (1997).</li><li>Francius, G., Domenech, O., Mingeot-Leclercq, M. P., Dufrene, Y. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+observation+of+Staphylococcus+aureus+cell+wall+digestion+by+lysostaphin.">Direct observation of Staphylococcus aureus cell wall digestion by lysostaphin.</a> J. Bacteriol. 190, 7904-7909 (2008).</li><li>Jordan, S., Hutchings, M. I., Mascher, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+envelope+stress+response+in+Gram-positive+bacteria.">Cell envelope stress response in Gram-positive bacteria.</a> FEMS Microbiol. Rev. 32, 107-146 (2008).</li><li>Koch, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bacterial+wall+as+target+for+attack:+past,+present,+and+future+research.">Bacterial wall as target for attack: past, present, and future research.</a> Clin. Microbiol. Rev. 16, 673-687 (2003).</li><li>Carpenter, A. 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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+common+mechanism+of+cellular+death+induced+by+bactericidal+antibiotics.">A common mechanism of cellular death induced by bactericidal antibiotics.</a> Cell. 130, 797-810 (2007).</li></ol>

在一组对甲氧西林敏感和耐甲氧西林金 黄色葡萄球菌 株10的实验中，对所提出的协议进行了验证和优化。因此，该协议未经修改应直接适用于其他菌株的 金黄色葡萄球菌 和其他抗生素与影响细菌细胞壁生物合成的行动机制。 除金黄色葡萄球菌外，细菌类型可能需要压力参数的变化：可溶性（酶）和机械应力。如果在葡萄 球菌 以外的细菌物种的测试中需要可?...

细菌耐药性的上升加剧了对基于表型的快速抗生素易感性测试的需求，以保障我们药物的最终手段。标准易感性测试基于细菌生长抑制，在抗生素的存在下需要多个小时（8-24）小时才能完成。我们在一个微型流体平台上开发了一种新的抗生素易感性测试，该平台依靠生物合成途径的压力激活来加速抗生素的作用。
微流体规模的抗生素易感性测试具有有效样品使用的优势，因为它们需要少量细菌。此外，微流体设备可以多路复用，以便在多个条件下测试多个样本1，2。最近，一些用于抗生素易感性检测的微流体方法被报道为3-9。在这些方法中，细菌生长在纳米和皮奥利特液滴3，7，在微流体通道4-6，8的全体积，或作为单一细菌电局部到通道9的底部表面。虽然这些测试是在微流体通道中进行的，但它们都监测微生物在存在和缺乏与传统方法类似的抗生素时的增长。生长测量 通过 光学密度、pH敏感染料或明亮的场/相对比度或荧光图像进行。虽然其中一些测试比传统方法更快，但它们各自被动地检测抗生素耐药性。换句话说，这些方法仍然要求用户等待细菌生长作为最终读出。
相比之下，我们开发了一种利用剪切和酶应力相结合的方法来激活抗生素敏感的生化途径10。用这些抗生素挑战压力细菌会产生更快的易感性测试。对抗生素有抗药性的细菌能够承受压力。另一方面，易感细菌会被合并的压力迅速杀死。用荧光死细胞污渍用显微镜测量一小时后细胞死亡的百分比，定义了细菌的表型（耐药性与易感性）。
要成功实施我们的方法，细菌必须固定在微流体通道的底部表面。这样，细菌可以承受各种压力，同时在单平面显微镜下成像。涂层显微镜玻璃滑梯用于细菌固定。幻灯片由制造商预涂，带有环氧酶组，用于非特异性蛋白质结合。这些环氧酶与细菌表面蛋白质的非特异性结合使细菌与滑动表面共度。
菌株在抗生素缺乏（控制）和存在（实验）的情况下在相同的条件下（剪切+酶应激）下进行测试。每个通道的相位对比度和荧光显微镜照片每两分钟自动拍摄一小时。然后通过比较实验通道中死细菌的百分比和控制通道中的细菌来进行耐药性指定。一小时后，细胞死亡率大于1%的样本被认为容易受到感染，而小于0.5%的死亡表明存在抵抗力。这两个截止点之间的百分比被认为是不确定的，必须再次测试样本。
微流体通道在 PDMS 中定义，这是微流体设备11的首选材料。PDMS 在波长广泛、生物相容、惰性、可渗透到气体中且对液体的渗透性较低：因此，它非常适合这些实验。
机械/剪切应力是由室温介质流过固定细菌而产生的。（注意：将介质变暖至 37 °C 对检测结果没有显著影响。自动注射器泵通过微流体通道（200μm x 400 μm）以1ml/min的流速强制介质（含有死细胞污渍+/-抗生素，以及可选的酶应激器），以6.25 kPa的剪切力或6，000秒-1的剪切速率。这个比率等于或超过先前研究的 葡萄球菌的剪切应力。
这种酶，溶酶，被选中进行初步实验，因为它对 葡萄球菌 细胞壁造成直接损害。溶酶素（0.7 ng/ml）的浓度足以造成细菌细胞壁损伤，但不足以在实验时限内在没有抗生素的情况下导致细菌细胞死亡。正确指定细菌易感性不需要溶酶素，但它确实增加了结果，导致易感菌株的细胞死亡增加。相比之下，剪切应力对检测功能至关重要。当甲氧西林敏感金 黄色葡萄球菌 株在没有流动的情况下用溶酶素和牛皮林治疗时，在实验过程中不会记录细胞死亡。
细胞的生存能力被监测与荧光死细胞污渍12。染料的选择基于其选择性地污渍只损坏细胞的能力，它对活细胞的无毒性，以及它的低背景荧光，这使得它能够直接添加到细胞介质没有额外的步骤。选择荧光染料浓度为 0.25 μM 是为了在 1.6 秒的荧光激发光暴露时间内达到可接受的信号水平。
在我们的初步研究中使用了β-乳酸，牛皮林。耐甲氧西林 的金黄色葡萄球菌 （MRSA）物种对牛皮林具有抗药性，在实验的时间范围内不会显示出任何明显的细胞死亡。初步研究确定了50微克/毫升的浓度。抗生素浓度较低，耐药菌株和易感菌株之间的分离较少，而高浓度不会在实验结果上产生明显差异。
我们以前曾报道过一项试验的成功开发，该测试将直接影响细菌细胞壁13 的机械和酶应力与抑制细胞壁生物合成的抗生素14，15相结合。这些原理证明实验是在MSA和甲氧西林敏感性 金黄色葡萄球菌 （MSSA）的小组中进行的。然而，在选择适当的实验参数时，我们的方法应适用于多种细菌和多种抗生素。

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	<tbody>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:195px;">SYTOX Green</td>
			<td dir="LTR" style="width:129px;">Invitrogen Corporation</td>
			<td dir="LTR" style="width:136px;">S7020</td>
			<td dir="LTR" style="width:175px;">Dead cell fluorescence stain</td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:195px;">Bovine Serum Albumin (BSA)</td>
			<td dir="LTR" style="width:129px;">Sigma Aldrich, Inc</td>
			<td dir="LTR" style="width:136px;">A9418-5G</td>
			<td dir="LTR" style="width:175px;">Used for lysostaphin storage</td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:195px;">Sodium Acetate</td>
			<td dir="LTR" style="width:129px;">Sigma Aldrich, Inc</td>
			<td dir="LTR" style="width:136px;">S8750-500G</td>
			<td dir="LTR" style="width:175px;">Used for lysostaphin storage</td>
		</tr>
		<tr height="98">
			<td dir="LTR" height="98" style="height:98px;width:195px;">Lysostaphin&#160;</td>
			<td dir="LTR" style="width:129px;">Cell Sciences</td>
			<td dir="LTR" style="width:136px;">CRL309A</td>
			<td dir="LTR" style="width:175px;">Arrives as 1 mg solid. For storage: Dissolve in 20 mM sodium acetate. Mix with BSA solution to final concentration of 1% BSA and 100 &#181;g/ml &#160;lysostaphin for storage&#160;</td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:195px;">Oxacillin salt</td>
			<td dir="LTR" style="width:129px;">Sigma Aldrich, Inc</td>
			<td dir="LTR" style="width:136px;">28221-1G</td>
			<td dir="LTR" style="width:175px;">Antibiotic</td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:195px;">Mueller Hinton Broth</td>
			<td dir="LTR" style="width:129px;">Fisher Scientific</td>
			<td dir="LTR" style="width:136px;">DF0757-17-6</td>
			<td dir="LTR" style="width:175px;"></td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:195px;">Sodium chloride</td>
			<td dir="LTR" style="width:129px;">Sigma Aldrixh</td>
			<td dir="LTR" style="width:136px;">S3014-500G</td>
			<td dir="LTR" style="width:175px;">2% added to Mueller-Hilton broth prior to autoclaving</td>
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		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:195px;">1 ml, Luer-lock syringe&#160;</td>
			<td dir="LTR" style="width:129px;">BD (Beckton, Dickinson and Comp.)</td>
			<td dir="LTR" style="width:136px;">14-823-2F</td>
			<td dir="LTR" style="width:175px;"></td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:195px;">2 oz, Luer-lock syringe</td>
			<td dir="LTR" style="width:129px;">BD (Beckton, Dickinson and Comp.)</td>
			<td dir="LTR" style="width:136px;">309653 - 60 mL</td>
			<td dir="LTR" style="width:175px;">Overfill to ~65 ml</td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Microscope</td>
			<td dir="LTR" style="width:163px;"></td>
			<td dir="LTR" style="width:155px;"></td>
			<td dir="LTR" style="width:269px;"></td>
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			<td dir="LTR" height="22" style="height:22px;width:329px;">Inverted Fluoresccence Microscope Olympus IX-70</td>
			<td dir="LTR" style="width:163px;">Cambridge Scientific</td>
			<td dir="LTR" style="width:155px;">9349</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">60X, Fluorescence/Phase contrast objective</td>
			<td dir="LTR" style="width:163px;">Olympus Corp.</td>
			<td dir="LTR" style="width:155px;">LCPlan F1 60x/0.70 Ph2</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Retiga 12-bit monochrome CCD camera</td>
			<td dir="LTR" style="width:163px;">QImaging</td>
			<td dir="LTR" style="width:155px;">RET-4000R-F-M-12-C&#160;</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Microscope automation</td>
			<td dir="LTR" style="width:163px;"></td>
			<td dir="LTR" style="width:155px;"></td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Shutters phase contrast/fluorescence</td>
			<td dir="LTR" style="width:163px;">PRIOR Scientific</td>
			<td dir="LTR" style="width:155px;">H204/H202</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">X/Y Stage&#160;</td>
			<td dir="LTR" style="width:163px;">PRIOR Scientific</td>
			<td dir="LTR" style="width:155px;">H107AENN</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Focus motor</td>
			<td dir="LTR" style="width:163px;">PRIOR Scientific</td>
			<td dir="LTR" style="width:155px;">H122</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Joystick for XYZ control</td>
			<td dir="LTR" style="width:163px;">PRIOR Scientific</td>
			<td dir="LTR" style="width:155px;">CS152EF</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Proscan Controller</td>
			<td dir="LTR" style="width:163px;">PRIOR Scientific</td>
			<td dir="LTR" style="width:155px;">H3-XY2</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Image Acquisition Software</td>
			<td dir="LTR" style="width:163px;">Fraunhofer CMI</td>
			<td dir="LTR" style="width:155px;"></td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Flow Cell Assembly and PDMS</td>
			<td dir="LTR" style="width:163px;"></td>
			<td dir="LTR" style="width:155px;"></td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:329px;">Flow Cell</td>
			<td dir="LTR" style="width:163px;">BU Scientific Instruments Facility/Fraunhofer CMI</td>
			<td dir="LTR" style="width:155px;">3333-1044</td>
			<td dir="LTR" style="width:269px;">Engineering drawings were produced by Fraunhofer CMI</td>
		</tr>
		<tr height="33">
			<td dir="LTR" height="33" style="height:33px;width:329px;">Glass window</td>
			<td dir="LTR" style="width:163px;">Fraunhofer CMI</td>
			<td dir="LTR" style="width:155px;">3333-1054</td>
			<td dir="LTR" rowspan="2" style="width:269px;">Glass window was cut to the proper size at Fraunhofer CMI</td>
		</tr>
		<tr height="33">
			<td dir="LTR" height="33" style="height:33px;width:329px;">BOROFLOAT Window 50 mm x 50 mm</td>
			<td dir="LTR" style="width:163px;">Edmund Optics Inc.</td>
			<td dir="LTR" style="width:155px;">NT48-543</td>
		</tr>
		<tr height="50">
			<td dir="LTR" height="50" style="height:50px;width:329px;">Sealing plate</td>
			<td dir="LTR" style="width:163px;">BU Scientific Instruments Facility</td>
			<td dir="LTR" style="width:155px;">3333-1045</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Epoxide glass slide</td>
			<td dir="LTR" style="width:163px;">Arrayit Corporation</td>
			<td dir="LTR" style="width:155px;">SuperEpoxy 2</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="45">
			<td dir="LTR" height="45" style="height:45px;width:329px;">PDMS master</td>
			<td dir="LTR" style="width:163px;">Fraunhofer CMI</td>
			<td dir="LTR" style="width:155px;">3333-1053</td>
			<td dir="LTR" style="width:269px;">Master machined in aluminum or brass with UPM-0005 (ultrapresicion fly-cutting machine)</td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:329px;">PDMS slide design</td>
			<td dir="LTR" style="width:163px;">Fraunhofer CMI</td>
			<td dir="LTR" style="width:155px;">3333-1053</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:329px;">Tubing</td>
			<td dir="LTR" style="width:163px;"></td>
			<td dir="LTR" style="width:155px;"></td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="50">
			<td dir="LTR" height="50" style="height:50px;width:329px;">Nut, Super flangeless Tinytight, headless, 1/16 in, PEEK, green&#160;</td>
			<td dir="LTR" style="width:163px;">IDEX Health &#38; Science</td>
			<td dir="LTR" style="width:155px;">M-644-03</td>
			<td dir="LTR" style="width:269px;">Flow cell inputs/outputs are tapped for this ferrule</td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:329px;">Ferrule, Tinytight, 1/16 in, 6-40, .030 in TH, PEEK w/ SS lock ring, black</td>
			<td dir="LTR" style="width:163px;">IDEX Health &#38; Science</td>
			<td dir="LTR" style="width:155px;">M-657</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:329px;">Nut, Super flangeless Tinytight, headless, 1/16-1/32 in, 1/4-28, PEEK, natural</td>
			<td dir="LTR" style="width:163px;">IDEX Health &#38; Science</td>
			<td dir="LTR" style="width:155px;">P-255</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:329px;">Ferrule, Super Falngeless, 1/16 in, Tefzel (ETFE), yellow</td>
			<td dir="LTR" style="width:163px;">IDEX Health &#38; Science</td>
			<td dir="LTR" style="width:155px;">P-259</td>
			<td dir="LTR" style="width:269px;">Fits Luer-lock adapter</td>
		</tr>
		<tr height="22">
			<td dir="LTR" height="22" style="height:22px;width:329px;">Tubing, Teflon FEP, .030 in x 1/16 in x 20 ft, green&#160;</td>
			<td dir="LTR" style="width:163px;">IDEX Health &#38; Science</td>
			<td dir="LTR" style="width:155px;">1520G</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
		<tr height="34">
			<td dir="LTR" height="34" style="height:34px;width:329px;">Adapter, quick connect female Luer to female 1/4-28, PEEK, red&#160;</td>
			<td dir="LTR" style="width:163px;">IDEX Health &#38; Science</td>
			<td dir="LTR" style="width:155px;">P-658</td>
			<td dir="LTR" style="width:269px;"></td>
		</tr>
	</tbody>
</table>

stress-induced antibiotic susceptibility testing on a chip

我们已经开发出一种快速微流体方法，用于在压力型环境中进行抗生素易感性测试。流体以高速通过在微流体通道底部固定的细菌。在压力和抗生素的存在下，易感菌株会迅速死亡。然而，耐药细菌在这些紧张的条件下存活下来。这种方法背后的假设是新的：作为抗生素靶点的生化途径的压力激活可以加速抗生素易感性测试。与标准抗生素易感性检测方法相比，在抗生素应用过程中省略了限速步骤 - 细菌生长。该方法的技术实施是标准技术和创新方法的结合。该方法的标准部分包括细菌培养协议、多晶硅氧烷 （PDMS） 中的微流体通道定义、荧光细胞生存能力监测以及细菌计数的批量图像处理。该方法的创新部分是利用培养介质流进行机械应力应用，使用酶来损伤而不是杀死细菌，以及使用微阵拉基板进行细菌附着。开发平台可用于抗生素和非抗生素相关药物的开发和测试。与标准的细菌悬浮实验相比，该药物的效果可以在受控时间段内反复打开和关闭。在同一实验过程中，可以重复观察相同的细菌种群。

图4中提供的数据表明，在含抗生素的微流体通道中，金黄色葡萄球菌菌株会随着时间而发生反应。在 1 分钟和 1 小时实验结束时获得的相位对比图像显示在图 4A和B中。分析的 1 小时数据以图 4C显示，细菌以红色突出显示（共 5，828 个）。相应的荧光图像显示在图4D和E中。分析的 1 小时数据显示在图 4F...

Watch this Scientific Journal Video about Stress-induced Antibiotic Susceptibility Testing on a Chip at JoVE.com

Stress-induced Antibiotic Susceptibility Testing on a Chip

芯片上的压力诱导抗生素易感性测试

我们开发了一个用于快速抗生素易感性检测的微流体平台。流体以高速通过在微流体通道底部固定的细菌。在压力和抗生素的存在下，易感菌株会迅速死亡。然而，耐药细菌可以在这些紧张的条件下存活下来。

We have developed a rapid microfluidic method for antibiotic susceptibility testing in a stress-based environment. Fluid is passed at high speeds over ...

Research

JoVE Journal

Bioengineering

Lensless Fluorescent Microscopy on a Chip

片上的无透镜荧光显微镜

On-chip lensless imaging in general aims to replace bulky lens-based optical microscopes with simpler and more compact designs, especially for ...

科研

生物工程

On-Chip Endothelial Inflammatory Phenotyping

片上内皮炎症表型

Atherogenesis is potentiated by metabolic abnormalities that contribute to a heightened state of systemic inflammation resulting in endothelial ...

Procedure for the Development of Multi-depth Circular Cross-sectional Endothelialized Microchannels-on-a-chip

发展多深的圆形横截面微内皮化的一个芯片的程序

Efforts have been focused on developing in vitro assays for the study of microvessels because in vivo animal studies are more time-consuming, expensive, ...

PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions

PIP-on-a-chip：蛋白质 - 磷酸肌醇相互作用的无标记研究

Numerous cellular proteins interact with membrane surfaces to affect essential cellular processes. These interactions can be directed towards a specific ...

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

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 ...

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

用集成电极直接量化 Transendothelial 电阻的 Organ-on-chip 系统的制作与验证

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

A Lab-On-A-Chip Platform for Stimulating Osteocyte Mechanotransduction and Analyzing Functional Outcomes of Bone Remodeling

用于刺激骨质复变和分析骨骼重塑功能结果的实验室A芯片平台

Bone remodeling is a tightly regulated process that is required for skeletal growth and repair as well as adapting to changes in the mechanical ...

3D Cell-Printed Hypoxic Cancer-on-a-Chip for Recapitulating Pathologic Progression of Solid Cancer

3D 细胞打印的芯片上低氧癌症，用于回顾固体癌症的病理进展

Cancer microenvironment has a significant impact on the progression of the disease. In particular, hypoxia is the key driver of cancer survival, invasion, ...

Generation of a Simplified Three-Dimensional Skin-on-a-chip Model in a Micromachined Microfluidic Platform

在微加工微流体平台中生成简化的三维芯片皮肤模型

This work presents a new, cost-effective, and reliable microfluidic platform with the potential to generate complex multilayered tissues. As a proof of ...

Creation of a Knee Joint-on-a-Chip for Modeling Joint Diseases and Testing Drugs

创建膝关节芯片，用于关节疾病建模和药物测试

The high prevalence of debilitating joint diseases like osteoarthritis (OA) poses a high socioeconomic burden. Currently, the available drugs that target ...