This work was funded by start-up funds provided to Dr. Silviya Zustiak by Saint Louis University as well as by a President&#8217;s Research Fund (PRF) grant awarded to Dr. Silviya Zustiak by Saint Louis University. We thank Naveed Ahmed and Keval Shah for technical assistance.

1.准备水凝胶有关的解决方案和等分<ol><li>制备的聚丙烯酰胺凝胶前体溶液。 <ol><li>通过混合丙烯酰胺（A）中制备的聚丙烯酰胺凝胶前体溶液（40％w / v的，M R71.08克/摩尔），交联剂双丙烯酰胺（B）（2％w / v的，M R154.17克/摩尔），和DE-离子水在表1中规定的体积百分比。 注意：这些解决方案能在大批量制备，并储存在4℃下进行长达数月。 <ol><li>注意：丙烯酰胺是在吸入或摄入有毒，特别是，当以粉末形式：因此，优选使用40％w / v的溶液，以降低毒性风险。只处理而穿着防护服，如手套，护目镜，以及白大褂。在储存在冰箱的耐光，密闭的容器中（&lt;23°C，通风良好的地方）。 </li><li>注意：双 - 丙烯酰胺是在吸入或摄入有毒，特别是，粉末形式时：因此，优选使用2％w / v的溶液，以降低毒性风险。只处理而穿着防护服，如手套，护目镜，以及白大褂。在储存在冰箱（&lt;4°C，通风良好的地方）光性，密闭容器内。 </li></ol></li></ol></li><li>制备和 N -Sulfosuccinimidyl -6-（4&#39;-叠氮基-2&#39;-硝基苯基氨基）己酸的使用量（磺基SANPAH，M R492.40克/ mol）的等分试样。注意：磺基SANPAH造成严重眼刺激;手套和适当的眼部或面部防护处理。储存于-20℃，在​​收到和前分装。 <ol><li>以存储磺基SANPAH：50毫克/毫升溶解磺基SANPAH在dimethylsulfoxane（DMSO）中。分装原液到每管20微升50微离心管中。在干冰上，或在液氮中闪冻（任选的但优选的步骤，以保持最大效率交联剂），并存储在-80℃。 注：CA等分N为存放数个月。 </li><li>使用磺基SANPAH：解冻的等分试样简要和稀释在480微升去离子水。立即使用。磺SANPAH迅速水解水：所以采取谨慎快速执行上述所有步骤。 </li></ol></li><li>准备过硫酸铵（Mr为228.18克/摩尔）等分。 注意：过硫酸铵引起眼睛，皮肤和呼吸系统有刺激性。处理时，佩戴合适的个人防护装备。处理过硫酸铵粉末在化学通风橱中。粉储存在干燥，通风良好的地方。一旦分装，稀溶液可用于在工作台上。 <ol><li>溶解过硫酸铵在去离子水以达到最终的过硫酸铵浓度为10％w / v的。分装和储存在-20℃。解冻使用前立即。 </li></ol></li><li>制备胶原蛋白I型的解决方案。 <ol><li>制备0.2mg / ml的胶原溶液稀释储备所以lution在pH为7.4的1×磷酸盐缓冲盐水（PBS）中。储存在冰短暂或稀释后立即使用。 </li></ol></li></ol> 2.水凝胶的制备（参见图1） <ol><li>制备的疏水载玻片上。 <ol><li>放置几滴疏水溶液在玻璃板上，并用纸巾在表面上传播。让空气干燥，并再次用纸巾擦拭纸拉平疏水涂层。 注：易燃内阁在室温储存疏水性的解决方案。处理时佩戴个人防护装备。在通风良好的地方工作。 </li></ol></li><li>制备的柔性塑料支撑。 <ol><li>切割柔性塑料支撑以匹配疏水涂覆玻璃板的尺寸。 </li><li>通过轻轻搔抓用尖锐的工具的表面上，如手术刀马克挠性塑料支撑的疏水侧。 注意：一旦凝胶 - 这是完全透明的 - 烘的划痕将有助于区分哪些灵活的塑料支撑侧含有凝胶。 注：柔性塑料支撑具有疏水和亲水侧。一旦沉积，聚丙烯酰胺永久坚持的塑料支撑这有利于方便后续处理水凝胶的亲水性的一面。 </li></ol></li><li>凝胶法制备（例如卷，给出了5毫升凝胶前体解决方案）。 注：5毫升将足以产生〜40的凝胶时的凝胶的初始厚度为0.5毫米。更多的凝胶可以生产如果凝胶厚度减小。 <ol><li>放置4972.5微升期望的最终浓度（ 表1）的聚丙烯酰胺的前体溶液到50毫升锥形管中。放置在脱气室30分钟以打开盖子。 注：氧气用作自由基捕集和当存在时，其抑制聚合。 </li><li>添加25微升10％w / v的过硫酸铵（参照点1.3）以达到最终的0.05％过硫酸铵浓度。 </li><li>加入2.5微升的N，N，N&#39;，N&#39;-四甲基乙二胺（TEMED，M R116.24克/摩尔）于脱气的凝胶溶液以达到0.5％的最终TEMED浓度。 注：储存TEMED在易燃内阁在室温。穿着适当的个人防护设备时，处理化学通风柜。保持在惰性气体密闭的，因为它是高度空气和水分敏感。 </li><li> 5倍 - 吹打向上和向下轻轻3混合的解决方案。不要旋涡振荡，以避免氧扩散到凝胶前体溶液。 </li><li>吸管将凝胶溶液涂布在柔性塑料支撑和三明治用疏水涂层玻璃载片的亲水侧。具有所需厚度（ 例如，0.5mm）的硅隔板分开的两个幻灯片。离开的聚合物前体溶液少量（约100微升）在50毫升锥形管作为凝胶化的指标来使用。 注意：任何间隔可被使用。例如，封口膜的单个条给出了100的最终的溶胀凝胶的厚度 - 120微米。 </li><li>将另一玻璃板上盖的弹性塑料支撑/凝胶三明治聚合后确定的，即使水凝胶表面。 </li><li>让凝胶聚合​​45分钟，尽管更少的时间，可用于较高的％（重量）的凝胶，如果需要的。以确定该凝胶已聚合，观察在50ml锥形管中的剩余溶液;如果剩余的溶液已凝胶化，则很可能该凝胶在玻璃板已被启动以及。但是请注意，模具过早开放将防止完全聚合。 </li><li>一旦凝胶形成，剥离的柔性塑料支撑在顶部具有共价附着的聚丙烯酰胺凝胶，并设置凝胶朝上风干。 注：对流或热干燥，也可用于加速此步骤。一旦干燥到柔性塑料支撑，该凝胶可以是存储无限期ð。 <ol><li>纪念弹性塑料的支持，其中聚丙烯酰胺凝胶并没有因为泡沫形成的裸露的斑点。标记而凝胶仍水合，因为这将融合在一起的柔性塑料支撑一旦凝胶干燥。 </li></ol></li></ol></li></ol> 3.多孔板组装，胶原蛋白涂层和灭菌<ol><li>多孔板组件。 <ol><li>一旦干燥，切成PA凝胶成所需的形状。 <ol><li>对于一个96孔板中，使用重型打孔器，直径为〜6mm之间。使用重型切纸机切断的凝胶成正方形或矩形形状。或者，用剪刀。 </li></ol></li><li>根据制造商的说明每96孔板制备约500微升的PDMS。胶水凝胶到多孔板的底部，放置一个小墨滴（〜5微升）聚二甲基硅氧烷（PDMS）中的的中央各孔中。使用镊子，将一个聚丙烯酰胺ë凝胶在各孔中，柔性塑料支撑面朝下。为了让PDMS治愈，留下的组装板在37℃最少4小时的。 </li></ol></li><li>聚丙烯酰胺凝胶的胶原蛋白涂层。 <ol><li>用移液管，将少量 - 磺基 - SANPAH（7 8微升）（参照点1.2.2）的各孔中，涡流从一侧到另一侧涂覆凝胶表面均匀。工作迅速自磺基SANPAH并不稳定在水中。 </li><li>放置孔板下高强度UV灯（强度= 37毫瓦，λ= 302 - 365 nm）的5分钟。冲洗用PBS凝胶以除去过量的磺基 - SANPAH。 </li><li>吸管将50μl0.2mg / ml的I型胶原溶液（参照点1.4）到每个孔中。留在4℃下覆盖在RT至少2小时或O / N的板。 注意：为了加快胶原涂层的过程中，移液管可用于添加胶原溶液。通常情况下，1 - 2液滴的溶液应该是足以完成LY覆盖凝胶表面。 </li><li>离开孔板在RT至少2小时，以允许胶原粘接。 </li><li>用PBS冲洗以除去过量的胶原蛋白溶液和UV（λ= 200纳米）下消毒的组织培养罩2小时。 </li><li>泡在完全培养基（参见4.1节的培养基成分）O / N来滋润和平衡的凝胶。用于小区在冰箱立即或商店播种长达2天。 </li></ol></li></ol>在PA刚度试验4.细胞种植注意：虽然典型的常见的哺乳动物细胞系，在这个部分中所概述的协议进行具体的乳腺癌MDA-MB-231细胞系中使用（ 见图4和5）。 <ol><li>通过暴露收集从组织培养烧瓶中的细胞，以5％的胰蛋白酶/ EDTA进行5分钟，在37℃。使用〜80微升胰蛋白酶/ EDTA的每培养瓶中区的每厘米2;例如，使用2个ml胰蛋白酶/ EDTA的FORA T25细胞培养瓶中。重悬浮收集的细胞中，在所期望的最终细胞浓度补充有10％胎牛血清（FBS）和1％青霉素/链霉素的完全培养基。考虑到细胞倍增时间，以及时间的细胞将被接种上测定的长度，选择适当的子汇合细胞浓度。确保补充介质是足以完全浸没水凝胶。 注意：由于该水凝胶已预平衡的培养基（参见步骤3.2.6）加入100μl体积应该是足够的。用于多孔板的典型介质体积应足以自凝胶已预平衡的培养基在上一步。 注：该测定是适当的任何附着依赖性细胞类型。 <ol><li>通过使用血细胞计数器计数倒置显微镜下的细胞数。负载10微升细胞悬液到每个血球端口和至少8个象限​​平均细胞计数。为了得到最终的细胞浓度，以10 4乘以细胞计数。 注：当在每个血球细胞象限数为20的最佳细胞计数结果获得 - 50。 </li></ol></li><li>培养在37℃下将细胞到PA的刚度测定的加湿培养箱和5％的CO 2。更换介质每2 - 3天。 5分钟需要通过暴露于5％胰蛋白酶/ EDTA，在37℃时收集细胞。使用〜80微升胰蛋白酶/ EDTA的每组织培养瓶的厘米2。在所有电池操作的步骤，特别注意不要破坏凝胶面：吸或吸液管中通过略微倾斜的多孔板侧身触摸枪头到侧壁各井，而不是触摸水凝胶。 注：除采取特别小心不要损坏在标准的组织培养处理的水凝胶表面，将细胞接种到刚性测定法可以被操纵以同样的方式，就好像它们接种在到正规的多孔板。 </li></ol> 5.成像细胞接种于PA刚度分析<ol><li>图像细胞直接作用于PA刚度检测。 注意：任何显微镜 - 倒置，荧光，或共焦，可用于细胞成像。 注意：用于构造刚度试验的软塑料的支持是完全透明的，不autofluoresce或干扰细胞成像。然而，即使在柔性塑料支撑本身是透明的，成像能力将通过物镜的工作距离的限制。柔性塑料支撑体的厚度为0.23毫米，10X物镜的一个典型的工作距离是〜4毫米，大幅降低为较高倍率。 <ol><li>活细胞成像，在显微镜板夹和图像位置PA刚度检测。保持成像会议下2小时，或使用配有环境室长成像倍的显微镜。 </li><li>当活细胞IM老化是不是目的，固定的细胞在4％的甲醛溶液补充有0.1％的清洁剂。浸泡细胞固定液在室温下最少2小时的。用PBS冲洗两次。丢弃固定液浪费在指定的废物容器。 注：细胞可以立即被成像或存储浸没在PBS中，在4℃下进行最多2周。注意：甲醛是对吸入和接触有毒。处理与化学通风柜手套。 注：细胞固定协议具有基于所述随后的细胞染色和处理协议被选择，因为某些固定剂损坏某些细胞蛋白。 </li><li>对于荧光成像，染色固定的细胞具有所需的细胞在多孔板直接染色。图像立即。 </li></ol></li></ol>

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The authors have nothing to disclose.

聚丙烯酰胺凝胶，最初开发用于电泳28现在常规用作细胞培养基材来研究衬底刚度对细胞形态，运动性，并且除其他细胞特征的通信3,24,29的影响。聚丙烯酰胺允许操纵衬底刚度以包含在身体的所有软组织的刚度（0.3 - 300千帕）1，在聚合物前体浓度的简单改变（ 图2，表1中 ，也见参考文献17,25,26）。耦合到一个事实，即PA的凝胶是相当便宜和简单的制备...

大多数组织在体内是软的粘弹性材料具有的杨氏模量为0.1千帕为脑至100千帕软软骨，然而，大多数体外细胞研究的是组织培养聚苯乙烯（TCP）的进行，其具有〜1京帕的模量1，本刚度匹配极大地影响方式细胞所处的环境做出反应。越来越多的研究机构是这样的专用于阐明对各种细胞类型，2,3-包括干细胞。4，结果的命运衬底刚度的效果，多水凝胶已经开发了在刚性依赖的细胞的帮助理解生物学包括聚丙烯酰胺（PA），5-7聚乙二醇（PEG），8,9-二甲基硅氧烷（PDMS），10和藻酸盐。11虽然这种衬底刚度对细胞命运产生重大影响的证据正在增长，大多数研究的进行上小规模用少量第amples。在基板刚度的细胞类型或环境条件是罕见的数组效果系统，多维的研究。12 几个有前途的高通量凝胶技术已被开发出来，其中包括基于PEG的微阵列，用于生产琼脂糖凝胶微珠，14或微和纳米棒，其中刚度由微米棒的直径和高度调制13的微流体装置15不过的技术来制备这样的基体是复杂的，并提供给限于实验室的数目。许多研究涉及刚度调制细胞应答使用聚丙烯酰胺（PA）的凝胶，这是不仅便宜和简单的实现，但也显示出杨氏模量，即0.3的生理学相关范围- 300千帕16-22但是，现有的方法来制造的PA凝胶为细胞培养是劳动密集型的，因此制备ARED小批量。从该凝胶中必须准备的规定部分与P​​A的凝胶作为细胞底物的制备相关的困难茎：1）在不存在氧，以允许完全聚合，2）具有平坦和光滑的表面，以允许均匀的细胞附着和铺展，和3）永久地固定在细胞培养皿为了防止浮动的底部。 几个小组已尝试产生的PA的凝胶为细胞培养在大批量。塞姆勒等人制备的厚片的PA凝胶中，将其“切断”用打孔器并置于96孔板中。23然而，该方法仅限于更硬的凝胶， 即 &gt; 1千帕在杨氏模量，因为较软的凝胶是“粘性”，难以切割，且容易损坏。 MIH 等人开发出了更复杂的技术，它允许对凝胶直接聚合在玻璃底多孔板。 <s达&gt; 6这是通过浇注胶解决方案集成到功能化玻璃底板和“夹”他们自定义的玻璃罩阵列形成凝胶达到6虽然非常有前途的，轻微的边缘效应仍在使用这种技术观察。此外，该技术需要定制设计的阵列不立即向许多实验室以及昂贵玻璃底多孔板访问。 本文介绍了一种简单而廉价的方式来组装PA凝胶中，可以很容易地通过任何实验室多孔板。这里，一个挠性塑料支撑被利用，其中有两个侧边 - 一个疏水性的，这是斥PA凝胶，和亲水性的，在沉积该共价结合的PA的凝胶。一旦PA凝胶片被淀积并永久地固定到柔性塑料支撑，它使得能够处理任何厚度或硬度的凝胶和切削成任何所需的形状。这APPRoach不仅产生定制的塑料“盖玻片&#39;的尺寸不否则市售，也省却了必要的预治疗玻璃表面，无论是玻璃盖玻片或昂贵的玻璃底多孔板的孔中，具有PA的粘合溶液，这是一个繁琐和耗时的工序。最后，均匀的PA的凝胶片材可以在大批量制备并存储的去水合数月。 总之，这里介绍的测定法是一种改进的几个方面的现有的方法。首先，多孔板组装的过程中是有效的，并且所需要的材料的总成本是低的。其次，水凝胶生产大批量在一个单一的均匀的凝胶膜。最后，仅是商业上可用的材料是必需的。该测定的效用是通过探索基板刚度对细胞形态的影响，传播区域所示。

<table border="0" cellpadding="0" cellspacing="0" width="898">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Reagents</td>
			<td style="width:200px;"></td>
			<td style="width:187px;"></td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:303px;">40% Acrylamide</td>
			<td style="width:200px;">Bio-Rad</td>
			<td style="width:187px;">161-0140</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:303px;">2% Bis-acrylamide</td>
			<td style="width:200px;">Bio-Rad</td>
			<td style="width:187px;">161-0142</td>
			<td></td>
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		<tr height="20">
			<td height="20" style="height:21px;width:303px;">Ammonium Persulfate</td>
			<td style="width:200px;">Bio-Rad</td>
			<td style="width:187px;">161-07000</td>
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		<tr height="21">
			<td height="21" style="height:21px;width:303px;">TEMED</td>
			<td style="width:200px;">Sigma Aldrich</td>
			<td style="width:187px;">T9281</td>
			<td></td>
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		<tr height="20">
			<td height="20" style="height:21px;width:303px;">Sulfo-SANPAH</td>
			<td style="width:200px;">Thermo Scientific</td>
			<td style="width:187px;">22589</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:303px;">Collagen Type 1, from Rat tail, 3.68 mg/mL</td>
			<td style="width:200px;">BD Biosciences</td>
			<td style="width:187px;">354236</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Dimethyl sulfoxide (DMSO)</td>
			<td style="width:200px;">Fisher Scientific&#160;</td>
			<td style="width:187px;">BP231-100</td>
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			<td height="20" style="height:21px;width:303px;">Hydrophobic solution - Repel Silane&#160;</td>
			<td style="width:200px;">GE Healthcare Bio-Sciences</td>
			<td style="width:187px;">17-1332-01</td>
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			<td height="20" style="height:21px;width:303px;">PBS (1x), pH 7.4</td>
			<td style="width:200px;">HyClone</td>
			<td style="width:187px;">SH30256.01</td>
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		<tr height="41">
			<td height="41" style="height:42px;width:303px;">Polydimehylsiloxane (PDMS) [Slygard 182 Elastomer Kit]</td>
			<td style="width:200px;">Elsworth Adhesives</td>
			<td style="width:187px;">3097358-1004</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Tyrpsin/EDTA (10x)</td>
			<td style="width:200px;">Sigma Aldrich</td>
			<td style="width:187px;">44174</td>
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		<tr height="21">
			<td height="21" style="height:21px;width:303px;">RPMI-1640 Medium (1x)</td>
			<td style="width:200px;">HyClone</td>
			<td style="width:187px;">SH30027-02</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Fetal Bovine Serum</td>
			<td style="width:200px;">HyClone</td>
			<td style="width:187px;">SH30073-03</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Penicillin Streptomycin</td>
			<td style="width:200px;">MP Biomedicals</td>
			<td style="width:187px;">1670046</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Detergent - Triton-X</td>
			<td style="width:200px;">Sigma Aldrich</td>
			<td style="width:187px;">T8787</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Formaldehyde 37% Solution</td>
			<td style="width:200px;">Sigma Aldrich</td>
			<td style="width:187px;">F1635</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Bovine Serum Albumin (BSA)</td>
			<td style="width:200px;">Sigma Aldrich</td>
			<td style="width:187px;">A2153</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">BSA-based cell adhesion blocking kit - ECM Cell Adhesion Array Kit</td>
			<td style="width:200px;">Chemicon International</td>
			<td style="width:187px;">ECM540</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:200px;"></td>
			<td style="width:187px;"></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Disposable lab equipment</td>
			<td style="width:200px;"></td>
			<td style="width:187px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">flexible plastic support - GelBond PAG Film for Polyacrylamide Gels</td>
			<td style="width:200px;">GE Healthcare Bio-Sciences</td>
			<td style="width:187px;">309819</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Glass Plates</td>
			<td style="width:200px;">Slumpys</td>
			<td style="width:187px;">GBS4100SFSL</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">50 mL Conicals</td>
			<td style="width:200px;">Fisher Scinetific</td>
			<td style="width:187px;">3181345107</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">15 mL Conicals</td>
			<td style="width:200px;">FALCON</td>
			<td style="width:187px;">352097</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Micro centrifuge tubes</td>
			<td style="width:200px;">Fisher Scinetific</td>
			<td style="width:187px;">2 mL: 02681258</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">96-well plate (flat bottom)</td>
			<td style="width:200px;">Fisher Scinetific</td>
			<td style="width:187px;">12565501</td>
			<td></td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:303px;">Disposable Pipettes (1 mL, 2mL, 5mL, 10mL, 25 mL, 50mL)</td>
			<td style="width:200px;">Fisher Scinetific</td>
			<td style="width:187px;">1 mL: 13-678-11B, 2mL: 05214038, 5mL(FALCON): 357529, 10mL: 13-678-11E, 25mL: 13-678-11, 50mL: 13-678-11F</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">Glass Transfer Pipettes</td>
			<td style="width:200px;">Fisher Scinetific</td>
			<td style="width:187px;">5 3/4&#34;: 1367820A, 9&#34;:136786B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Pipette Tips (1-200uL, 101-1000uL)</td>
			<td style="width:200px;">Fisher Scinetific</td>
			<td style="width:187px;">2707509</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">Plastic Standard Disposable Transfer Pipettes</td>
			<td style="width:200px;">Fisher Scientific</td>
			<td style="width:187px;">13-711-9D</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Parafilm</td>
			<td style="width:200px;">PARAFILM&#160;</td>
			<td style="width:187px;">PM992</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Powder Free Examination Gloves</td>
			<td style="width:200px;">Quest</td>
			<td style="width:187px;">92897</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">Silicone spacers - Silicone sheet, 0.5 mm thick/13 cm x 18 cm</td>
			<td style="width:200px;">Grace Bio-Labs</td>
			<td style="width:187px;">JTR-S-0.5</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:200px;"></td>
			<td style="width:187px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Large/non-disposable lab equipment</td>
			<td style="width:200px;"></td>
			<td style="width:187px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">Light and Flourescent Microscope (Axiovert 200M)</td>
			<td style="width:200px;">Zeiss</td>
			<td style="width:187px;">3820005619</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Microscope Software</td>
			<td style="width:200px;">Zeiss</td>
			<td style="width:187px;">AxioVision Rel. 4.8.2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">UV oven</td>
			<td style="width:200px;">UVITRON</td>
			<td style="width:187px;">UV1080</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Vacuum chamber/degasser</td>
			<td style="width:200px;">BelArt</td>
			<td style="width:187px;">999320237</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Vacuum pump for degasser</td>
			<td style="width:200px;">KNF Lab</td>
			<td style="width:187px;">5097482</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Tissue Culture Hood</td>
			<td style="width:200px;">NUAIRE</td>
			<td style="width:187px;">NU-425-600</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Chemical Fume Hood</td>
			<td style="width:200px;">KEWAUNEE</td>
			<td style="width:187px;">99151</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Inverted Microscope (Axiovert 25)</td>
			<td style="width:200px;">Zeiss</td>
			<td style="width:187px;">663526</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Incubator</td>
			<td style="width:200px;">NUAIRE</td>
			<td style="width:187px;">NU-8500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Pipette Aid</td>
			<td style="width:200px;">Drummond Scientific Co.</td>
			<td style="width:187px;">P-76864</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Hemacytometer</td>
			<td style="width:200px;">Bright-Line</td>
			<td style="width:187px;">383684</td>
			<td></td>
		</tr>
	</tbody>
</table>

simple polyacrylamide-based multiwell stiffness assay for the study of stiffness-dependent cell responses

Currently, most of the in vitro cell research is performed on rigid tissue culture polystyrene (~1 GPa), while most cells in the body are attached to a matrix that is elastic and much softer (0.1 &#8211; 100 kPa). Since such stiffness mismatch greatly affects cell responses, there is a strong interest in developing hydrogel materials that span a wide range of stiffness to serve as cell substrates. Polyacrylamide gels, which are inexpensive and cover the stiffness range of all soft tissues in the body, are the hydrogel of choice for many research groups. However, polyacrylamide gel preparation is lengthy, tedious, and only suitable for small batches. Here, we describe an assay which by utilizing a permanent flexible plastic film as a structural support for the gels, enables the preparation of polyacrylamide gels in a multiwell plate format. The technique is faster, more efficient, and less costly than current methods and permits the preparation of gels of custom sizes not otherwise available. As it doesn&#8217;t require any specialized equipment, the method could be easily adopted by any research laboratory and would be particularly useful in research focused on understanding stiffness-dependent cell responses.

聚丙烯酰胺（PA）的水凝胶被广泛用来测试刚性依赖性细胞反应。17,24通过混合不同浓度的丙烯酰胺（A）和双-丙烯酰胺（B），可以使跨越大部分软组织中的刚度范围PA的凝胶主体- 0.3 - 300千帕的杨氏模量1但是，制备的聚丙烯酰胺凝胶的是乏味和耗时的，常常限制了其在“高通量”的应用，例如药物筛选效用12在这里，为简单而快速的方法组装的PA凝胶在多井板或任何其它期...

Watch this Scientific Journal Video about Simple Polyacrylamide-based Multiwell Stiffness Assay for the Study of Stiffness-dependent Cell Responses at JoVE.com

Simple Polyacrylamide-based Multiwell Stiffness Assay for the Study of Stiffness-dependent Cell Responses

Here, a method that enables quick, efficient, and inexpensive preparation of polyacrylamide gels in a multiwell plate format is described. The method does not require any specialized equipment and could be easily adopted by any research laboratory. It would be particularly useful in research focused on understanding stiffness-dependent cell responses.

简单的聚丙烯酰胺为基础的多井刚度检测方法的刚度依赖的细胞反应的研究

Currently, most of the in vitro cell research is performed on rigid tissue culture polystyrene (~1 GPa), while most cells in the body are attached to a ...

simple-polyacrylamide-based-multiwell-stiffness-assay-for-study

Research

JoVE Journal

Bioengineering

19.4K 次观看.  Saint Louis University. Here, a method that enables quick, efficient, and inexpensive preparation of polyacrylamide gels in a multiwell plate format is described. The method does not require any specialized equipment and could be easily adopted by any research laboratory. It would be particularly useful in research focused on understanding stiffness-dependent cell responses.

视频: Simple Polyacrylamide-based Multiwell Stiffness Assay for the Study of Stiffness-dependent Cell Responses

Bioluminescence Imaging for Assessment of Immune Responses Following Implantation of Engineered Heart Tissue (EHT)

Various techniques of cardiac tissue engineering have been pursued in the past decades including scaffolding strategies using either native or bioartificial scaffold materials, entrapment of cardiac myocytes in hydrogels such as fibrin or collagen and stacking of myocyte monolayers 1. These concepts aim at restoration of compromised cardiac function (e.g. after myocardial infarction) or as experimental models (e.g. predictive toxicology and substance screening or disease modelling). Precise monitoring of cell survival after implantation of engineered heart tissue (EHT) has now become possible using in-vivo bioluminescence imaging (BLI) techniques 2. Here we describe the generation of fibrin-based EHT from a transgenic rat strain with ubiquitous expression of firefly luciferase (ROSA/luciferase-LEW Tg; 3). Implantation is performed into the greater omentum of different rat strains to assess immune responses of the recipient organism following EHT implantation. Comparison of results generated by BLI and the Enzyme Linked Immuno Spot Technique (ELISPOT) confirm the usability of BLI for the assessment of immune responses.

Bioluminescence Imaging for Assessment of Immune Responses Following Implantation of Engineered Heart Tissue EHT

This video demonstrates the use of in vivo bioluminescence imaging to study immune responses after implantation of Engineered Heart Tissue (EHT) in rats.

生物发光成像评估的免疫反应，植入心脏组织工程（东隧）

Various techniques of cardiac tissue engineering have been pursued in the past decades including scaffolding strategies using either native or ...

科研

生物工程

A Simple Hanging Drop Cell Culture Protocol for Generation of 3D Spheroids

Studies of cell-cell cohesion and cell-substratum adhesion have historically been performed on monolayer cultures adherent to rigid substrates. Cells within a tissue, however, are typically encased within a closely packed tissue mass in which cells establish intimate connections with many near-neighbors and with extracellular matrix components. Accordingly, the chemical milieu and physical forces experienced by cells within a 3D tissue are fundamentally different than those experienced by cells grown in monolayer culture. This has been shown to markedly impact cellular morphology and signaling. Several methods have been devised to generate 3D cell cultures including encapsulation of cells in collagen gels1or in biomaterial scaffolds2. Such methods, while useful, do not recapitulate the intimate direct cell-cell adhesion architecture found in normal tissues. Rather, they more closely approximate culture systems in which single cells are loosely dispersed within a 3D meshwork of ECM products. Here, we describe a simple method in which cells are placed in hanging drop culture and incubated under physiological conditions until they form true 3D spheroids in which cells are in direct contact with each other and with extracellular matrix components. The method requires no specialized equipment and can be adapted to include addition of any biological agent in very small quantities that may be of interest in elucidating effects on cell-cell or cell-ECM interaction. The method can also be used to co-culture two (or more) different cell populations so as to elucidate the role of cell-cell or cell-ECM interactions in specifying spatial relationships between cells. Cell-cell cohesion and cell-ECM adhesion are the cornerstones of studies of embryonic development, tumor-stromal cell interaction in malignant invasion, wound healing, and for applications to tissue engineering. This simple method will provide a means of generating tissue-like cellular aggregates for measurement of biomechanical properties or for molecular and biochemical analysis in a physiologically relevant model.

We describe a simple, rapid method of generating 3D tissue-like spheroids and their potential application to quantify differences in cell-cell interactions.

一个简单的悬滴细胞生成三维球体文化协议

Studies of cell-cell cohesion and cell-substratum adhesion have historically been performed on monolayer cultures adherent to rigid substrates. Cells ...

Organotypic Collagen I Assay: A Malleable Platform to Assess Cell Behaviour in a 3-Dimensional Context

Cell migration is fundamental to many aspects of biology, including development, wound healing, the cellular responses of the immune system, and metastasis of tumor cells. Migration has been studied on glass coverslips in order to make cellular dynamics amenable to investigation by light microscopy. However, it has become clear that many aspects of cell migration depend on features of the local environment including its elasticity, protein composition, and pore size, which are not faithfully represented by rigid two dimensional substrates such as glass and plastic 1. Furthermore, interaction with other cell types, including stromal fibroblasts 2 and immune cells 3, has been shown to play a critical role in promoting the invasion of cancer cells. Investigation at the molecular level has increasingly shown that molecular dynamics, including response to drug treatment, of identical cells are significantly different when compared in vitro and in vivo 4. 
Ideally, it would be best to study cell migration in its naturally occurring context in living organisms, however this is not always possible. Intermediate tissue culture systems, such as cell derived matrix, matrigel, organotypic culture (described here) tissue explants, organoids, and xenografts, are therefore important experimental intermediates. These systems approximate certain aspects of an in vivo environment but are more amenable to experimental manipulation such as use of stably transfected cell lines, drug treatment regimes, long term and high-resolution imaging. Such intermediate systems are especially useful as proving grounds to validate probes and establish parameters required to image the dynamic response of cells and fluorescent reporters prior to undertaking imaging in vivo 5. As such, they can serve an important role in reducing the need for experiments on living animals.

A method is described for the preparation of a 3-dimensional matrix consisting of collagen type I and primary human fibroblasts. This organotypic gel serves as a useful substrate to assess invasive cell migration because it mimics basic features of tissue stroma and is amenable to many forms of microscopy.

器官Ⅰ型胶原的含量可延展的平台，以评估细胞行为的一个3维的情况下

Cell migration is fundamental to many aspects of biology, including development, wound healing, the cellular responses of the immune system, and ...

Cell-based Calcium Assay for Medium to High Throughput Screening of TRP Channel Functions using FlexStation 3

The Molecular Devices' FlexStation 3 is a benchtop multi-mode microplate reader capable of automated fluorescence measurement in multi-well plates. It is ideal for medium- to high-throughput screens in academic settings. It has an integrated fluid transfer module equipped with a multi-channel pipetter and the machine reads one column at a time to monitor fluorescence changes of a variety of fluorescent reagents. For example, FlexStation 3 has been used to study the function of Ca2+-permeable ion channels and G-protein coupled receptors by measuring the changes of intracellular free Ca2+ levels. Transient receptor potential (TRP) channels are a large family of nonselective cation channels that play important roles in many physiological and pathophysiological functions. Most of the TRP channels are calcium permeable and induce calcium influx upon activation. In this video, we demonstrate the application of FlexStation 3 to study the pharmacological profile of the TRPA1 channel, a molecular sensor for numerous noxious stimuli. HEK293 cells transiently or stably expressing human TRPA1 channels, grown in 96-well plates, are loaded with a Ca2+-sensitive fluorescent dye, Fluo-4, and real-time fluorescence changes in these cells are measured before and during the application of a TRPA1 agonist using the FLEX mode of the FlexStation 3. The effect of a putative TRPA1 antagonist was also examined. Data are transferred from the SoftMax Pro software to construct concentration-response relationships of TRPA1 activators and inhibitors.

This video provides a detailed protocol for studying the pharmacological profile of human TRPA1 channels using FlexStation 3. The protocol covers details of cell preparation, dye loading and operation of the microplate reader, FlexStation 3.

基于细胞中钙含量TRP通道功能的高通量筛选，使用FlexStation 3

The Molecular Devices' FlexStation 3 is a benchtop multi-mode microplate reader capable of automated fluorescence measurement in multi-well plates.  It is ...

Adhesion Frequency Assay for In Situ Kinetics Analysis of Cross-Junctional Molecular Interactions at the Cell-Cell Interface

The micropipette adhesion assay was developed in 1998 to measure two-dimensional (2D) receptor-ligand binding kinetics1. The assay uses a human red blood cell (RBC) as adhesion sensor and presenting cell for one of the interacting molecules. It employs micromanipulation to bring the RBC into contact with another cell that expresses the other interacting molecule with precisely controlled area and time to enable bond formation. The adhesion event is detected as RBC elongation upon pulling the two cells apart. By controlling the density of the ligands immobilized on the RBC surface, the probability of adhesion is kept in mid-range between 0 and 1. The adhesion probability is estimated from the frequency of adhesion events in a sequence of repeated contact cycles between the two cells for a given contact time. Varying the contact time generates a binding curve. Fitting a probabilistic model for receptor-ligand reaction kinetics1 to the binding curve returns the 2D affinity and off-rate.
The assay has been validated using interactions of Fc&gamma; receptors with IgG Fc1-6, selectins with glycoconjugate ligands6-9, integrins with ligands10-13, homotypical cadherin binding14, T cell receptor and coreceptor with peptide-major histocompatibility complexes15-19.
The method has been used to quantify regulations of 2D kinetics by biophysical factors, such as the membrane microtopology5, membrane anchor2, molecular orientation and length6, carrier stiffness9, curvature20, and impingement force20, as well as biochemical factors, such as modulators of the cytoskeleton and membrane microenvironment where the interacting molecules reside and the surface organization of these molecules15,17,19.
The method has also been used to study the concurrent binding of dual receptor-ligand species3,4, and trimolecular interactions19 using a modified model21.
The major advantage of the method is that it allows study of receptors in their native membrane environment. The results could be very different from those obtained using purified receptors17. It also allows study of the receptor-ligand interactions in a sub-second timescale with temporal resolution well beyond the typical biochemical methods.
To illustrate the micropipette adhesion frequency method, we show kinetics measurement of intercellular adhesion molecule 1 (ICAM-1) functionalized on RBCs binding to integrin &alpha;L&beta;2 on neutrophils with dimeric E-selectin in the solution to activate &alpha;L&beta;2.

Adhesion Frequency Assay for In Situ Kinetics Analysis of Cross-Junctional Molecular Interactions at the Cell-Cell Interface

An adhesion frequency assay for measuring receptor-ligand interaction kinetics when both molecules are anchored on the surfaces of the interacting cells is described. This mechanically-based assay is exemplified using a micropipette-pressurized human red blood cell as adhesion sensor and integrin &alpha;L&beta;2 and intercellular adhesion molecule-1 as interacting receptors and ligands.

粘附频率含量为原位跨交界的分子相互作用，在细胞与细胞界面的动力学分析

The micropipette adhesion assay was developed in 1998 to measure two-dimensional (2D) receptor-ligand binding kinetics1. The assay uses a human red blood ...

Micropipette Aspiration of Substrate-attached Cells to Estimate Cell Stiffness

Growing number of studies show that biomechanical properties of individual cells play major roles in multiple cellular functions, including cell proliferation, differentiation, migration and cell-cell interactions. The two key parameters of cellular biomechanics are cellular deformability or stiffness and the ability of the cells to contract and generate force. Here we describe a quick and simple method to estimate cell stiffness by measuring the degree of membrane deformation in response to negative pressure applied by a glass micropipette to the cell surface, a technique that is called Micropipette Aspiration or Microaspiration.
Microaspiration is performed by pulling a glass capillary to create a micropipette with a very small tip (2-50 &mu;m diameter depending on the size of a cell or a tissue sample), which is then connected to a pneumatic pressure transducer and brought to a close vicinity of a cell under a microscope. When the tip of the pipette touches a cell, a step of negative pressure is applied to the pipette by the pneumatic pressure transducer generating well-defined pressure on the cell membrane. In response to pressure, the membrane is aspirated into the pipette and progressive membrane deformation or "membrane projection" into the pipette is measured as a function of time. The basic principle of this experimental approach is that the degree of membrane deformation in response to a defined mechanical force is a function of membrane stiffness. The stiffer the membrane is, the slower the rate of membrane deformation and the shorter the steady-state aspiration length.The technique can be performed on isolated cells, both in suspension and substrate-attached, large organelles, and liposomes.
Analysis is performed by comparing maximal membrane deformations achieved under a given pressure for different cell populations or experimental conditions. A "stiffness coefficient" is estimated by plotting the aspirated length of membrane deformation as a function of the applied pressure. Furthermore, the data can be further analyzed to estimate the Young's modulus of the cells (E), the most common parameter to characterize stiffness of materials. It is important to note that plasma membranes of eukaryotic cells can be viewed as a bi-component system where membrane lipid bilayer is underlied by the sub-membrane cytoskeleton and that it is the cytoskeleton that constitutes the mechanical scaffold of the membrane and dominates the deformability of the cellular envelope. This approach, therefore, allows probing the biomechanical properties of the sub-membrane cytoskeleton.

Here we describe a quick and simple method to measure cell stiffness. The general principle of this approach is to measure membrane deformation in response to well-defined negative pressure applied through a micropipette to the cell surface. This method provides a powerful tool to study biomechanical properties of substrate-attached cells.

基质贴壁细胞的微管吸吮的估计单元刚度

Growing number of studies show that biomechanical properties of individual cells play major roles in multiple cellular functions, including cell ...

Using Microfluidics Chips for Live Imaging and Study of Injury Responses in Drosophila Larvae

Live imaging is an important technique for studying cell biological processes, however this can be challenging in live animals. The translucent cuticle of the Drosophila larva makes it an attractive model organism for live imaging studies. However, an important challenge for live imaging techniques is to noninvasively immobilize and position an animal on the microscope. This protocol presents a simple and easy to use method for immobilizing and imaging Drosophila larvae on a polydimethylsiloxane (PDMS) microfluidic device, which we call the 'larva chip'. The larva chip is comprised of a snug-fitting PDMS microchamber that is attached to a thin glass coverslip, which, upon application of a vacuum via a syringe, immobilizes the animal and brings ventral structures such as the nerve cord, segmental nerves, and body wall muscles, within close proximity to the coverslip. This allows for high-resolution imaging, and importantly, avoids the use of anesthetics and chemicals, which facilitates the study of a broad range of physiological processes. Since larvae recover easily from the immobilization, they can be readily subjected to multiple imaging sessions. This allows for longitudinal studies over time courses ranging from hours to days. This protocol describes step-by-step how to prepare the chip and how to utilize the chip for live imaging of neuronal events in 3rd instar larvae. These events include the rapid transport of organelles in axons, calcium responses to injury, and time-lapse studies of the trafficking of photo-convertible proteins over long distances and time scales. Another application of the chip is to study regenerative and degenerative responses to axonal injury, so the second part of this protocol describes a new and simple procedure for injuring axons within peripheral nerves by a segmental nerve crush.

Using Microfluidics Chips for Live Imaging and Study of Injury Responses in Drosophila Larvae

Drosophila larvae are an attractive model system for live imaging due to their translucent cuticle and powerful genetics. This protocol describes how to utilize a single-layer PDMS device, called the &#39;larva chip&#39; for live imaging of cellular processes within neurons of 3rd instar Drosophila larvae.

使用微流体芯片实时成像和损伤研究的响应<em&gt;果蝇</em&gt;幼虫

Live imaging is an important technique for studying cell biological processes, however this can be challenging in live animals. The translucent cuticle of ...

Preparation of 3D Collagen Gels and Microchannels for the Study of 3D Interactions In Vivo

Historically, most cellular processes have been studied in only 2 dimensions. While these studies have been informative about general cell signaling mechanisms, they neglect important cellular cues received from the structural and mechanical properties of the local microenvironment and extracellular matrix (ECM). To understand how cells interact within a physiological ECM, it is important to study them in the context of 3 dimensional assays. Cell migration, cell differentiation, and cell proliferation are only a few processes that have been shown to be impacted by local changes in the mechanical properties of a 3-dimensional ECM. Collagen I, a core fibrillar component of the ECM, is more than a simple structural element of a tissue. Under normal conditions, mechanical cues from the collagen network direct morphogenesis and maintain cellular structures. In diseased microenvironments, such as the tumor microenvironment, the collagen network is often dramatically remodeled, demonstrating altered composition, enhanced deposition and altered fiber organization. In breast cancer, the degree of fiber alignment is important, as an increase in aligned fibers perpendicular to the tumor boundary has been correlated to poorer patient prognosis1. Aligned collagen matrices result in increased dissemination of tumor cells via persistent migration2,3. The following is a simple protocol for embedding cells within a 3-dimensional, fibrillar collagen hydrogel. This protocol is readily adaptable to many platforms, and can reproducibly generate both aligned and random collagen matrices for investigation of cell migration, cell division, and other cellular processes in a tunable, 3-dimensional, physiological microenvironment.

Preparation of 3D Collagen Gels and Microchannels for the Study of 3D Interactions In Vivo

Collagen is a core component of the ECM, and provides essential cues for several cellular processes ranging from migration to differentiation and proliferation. Provided here is a protocol for embedding cells within 3D collagen hydrogels, and a more advanced technique for generating randomized or aligned collagen matrices using PDMS microchannels.

3D胶原凝胶和微通道3D相互作用的研究准备<em&gt;在体内</em

Historically, most cellular processes have been studied in only 2 dimensions.  While these studies have been informative about general cell signaling ...

A Simple and Scalable Fabrication Method for Organic Electronic Devices on Textiles

Today, wearable electronics devices combine a large variety of functional, stretchable, and flexible technologies. However, in many cases, these devices cannot be worn under everyday conditions. Therefore, textiles are commonly considered the best substrate to accommodate electronic devices in wearable use. In this paper, we describe how to selectively pattern organic electroactive materials on textiles from a solution in an easy and scalable manner. This versatile deposition technique enables the fabrication of wearable organic electronic devices on clothes.

In this paper, we present a protocol to selectively deposit organic materials on textiles, which allows for the direct integration of organic electronic devices with wearables. The fabricated devices can be fully integrated in textiles, respecting their mechanical appearance and enabling sensing capabilities.

关于纺织品有机电子设备的简单和可扩展的制作方法

Today, wearable electronics devices combine a large variety of functional, stretchable, and flexible technologies. However, in many cases, these devices ...

3D Analysis of Multi-cellular Responses to Chemoattractant Gradients

Various limitations of 2D cell culture systems have sparked interest in 3D cell culture and analysis platforms, which would better mimic the spatial and chemical complexity of living tissues and mimic in vivo tissue functions. Recent advances in microfabrication technologies have facilitated the development of 3D in vitro environments in which cells can be integrated into a well-defined extracellular matrix (ECM) and a defined set of soluble or matrix associated biomolecules. However, technological barriers have limited their widespread use in research laboratories. Here, we describe a method to construct simple devices for 3D culture and experimentation with cells and multicellular organoids in 3D microenvironments with a defined chemoattractant gradient. We illustrate the use of this platform for analysis of the response of epithelial cells and organoids to gradients of growth factors, such as epidermal growth factor (EGF). EGF gradients were stable in the devices for several days leading to directed branch formation in breast organoids. This analysis allowed us to conclude that collective gradient sensing by groups of cells is more sensitive vs. single cells. We also describe the fabrication method, which does not require photolithography facilities nor advanced soft lithography techniques. This method will be helpful to study 3D cellular behaviors in the context of the analysis of development and pathological states, including cancer.

We describe a method to construct devices for 3D culture and experimentation with cells and multicellular organoids. This device allows analysis of cellular responses to soluble signals in 3D microenvironments with defined chemoattractant gradients. Organoids are better than single cells at detection of weak noisy inputs.

趋化梯度多细胞响应的三维分析

Various limitations of 2D cell culture systems have sparked interest in 3D cell culture and analysis platforms, which would better mimic the spatial and ...