我们承认通过赠款，CMMI 0854881 1066898 CBET从美国国家科学基金会的资助。感谢马修·穆伦斯有益的建议。

首先，我们描述一个一般的协议，可用于制造图案化的，密封的颗粒和可重构的把持装置。与一般的协议，我们提供了一个具体的，可视化的例子为制造密封十二面体颗粒和可重构microgrippers的。 1。面膜的制备与设计规则<ol><li>通常情况下，至少两个掩模集是需要的，一个不同地区，没有弯曲或曲线（刚性板）和其他不同地区，弯曲，曲线或密封件（铰链）。可以利用另外的掩膜定义的孔，分子的补丁，光学或电子元件的表面图案。面具可以设计使用各种二维矢量图形软件程序，如AutoCAD中的Adobe Illustrator，FreeHand MX的布局编辑器。 </li><li>实证研究提出下述的最佳的设计规则，用于产生口罩，可用于驱动的​​表面张力的聚合酶折叠yhedron侧长度L的<ol><li>对于某一个特定的多面体的几何形状，首先需要以确定面板的数目。例如，一个立方体有六十二面体的方板，同时有十二个五边形板。 </li><li>高产的二维布置的面板，也称为净需要想出。网具有最低的回转半径和二次顶点连接的最大数量，通常会组装的最高产量。的最佳网各种多面体如立方体，八面体，十二面体，截短八面体，二十面体的，发表23，28。 </li><li>面板中的掩模，多面体的面板应被绘制成网，并应隔开相邻的面板的间隙的宽度大约是0.1L。注册表标记所需的随后与铰链掩模对准。 </li><li>以铰链掩模，折叠铰链（在面板之间）和锁定或密封铰链（在面板的边缘），必须被定义。折叠铰链应该有0.8L和0.2L的宽度的长度的密封的外周的面板的铰链时，应该有0.1L 0.8L和宽度的长度与悬0.05L（图1中的交流）。一定要特别小心，以确保面板和铰链的面具覆盖，注册表。此设计原则，我们已经能够合成的颗粒尺寸从15微米到2.5厘米不等。 </li><li>的铰链的体积控制的折叠角度，并且，对于一个给定的铰链宽度，有限元建模所需的铰链，以确定所需的厚度。读者可以参考已出版的模型29-32来估计该厚度。然而，我们的方法的有吸引力的特点是使用的锁定或密封在自我折叠铰链，它们提供了相当大的误差公差。因此，当使用密封铰链，装配工艺是宽容的铰链卷的偏差，使他们能够仅约TArgeted。在装配过程中，由于显著的协同十二面体倍116.57°角已批量生产。此外，截断八面体有两个不同的二面角为125.27°109.47°，但可以使用相同的铰链卷组装。密封铰链的另一个好处是，相邻的铰链彼此熔丝上一起在折叠过程期间加热，创建在冷却的密封的，无缝的和刚性粒子。 </li></ol></li><li>实证研究表明，由于残余应力驱动的铰链折叠的面具microgrippers的优化设计规则。对于微夹钳的尖到尖的长度（D）的600至900微米，在铰链的间隙（g）通常为约50微米（图自由度为1）， ​​而对于较小microgrippers与一个 D为300μm，小克约25微米，应予以确认。的铰链的间隙尺寸取决于上的应力，厚度和弹性孔戴底层膜和多层解析解个核苷酸可用于粗略估计25,33折叠的程度。精确地测量压力和有限元建模需要精确模拟的折叠。实证研究表明，约100微米的下限为与预应力铬铰链的颗粒。 </li><li>在设计布局，口罩应印在透明胶片使用高分辨率打印机无论是在内部或通过各种商业网点（图2a）。通常情况下，透明膜应仅用于以最小的特征尺寸为6μm，而铬掩模所需的较小的铰链的间隙或功能的结构。典型的文件格式，所需的订货商业口罩是“DXF”。 </li></ol> 2。基材的准备<ol><li>如玻璃幻灯片或硅晶片的平坦衬底上需要被使用。 </li><li>良好的附着力，它是小鬼ortant基板清洁和干燥。清洁的基板用甲醇，丙酮和异丙醇（IPA），它一般是足够的，干燥氮气（N 2），并在热板上或在烘箱中在150℃下进行5-10分钟，然后将它们加热。 </li></ol> 3。沉积牺牲层为了释放的模板从构图后的基板，牺牲层是必需的。多种的任一金属构成的薄膜（ 例如 ，铜），介电层（ 例如 ，氧化铝）或聚合物（ 例如 ，聚甲基丙烯酸甲酯，聚乙烯醇，CYTOP等）可以利用。当选择一个牺牲膜时，需要考虑的重要因素是方便的材料和蚀刻选择性的沉积和溶解。 4。图案的面板<ol><li>沉积的颗粒的面板，可以通过各种各样的手段。对于聚合物颗粒，通过旋涂或滴铸膜沉积。为可以利用金属粒子，电沉积或热蒸发。 </li><li>如果在金属微粒的制造，它是要添加到所述牺牲层上涂布的基材的导电层，以方便的面板和铰链的电沉积。 </li><li>面板可以使用任何光刻工艺，诸如光刻法，成型，纳米压印光刻或电子束光刻构图。一个典型的光刻工艺涉及涂覆到基板上的光致抗蚀剂层，然后烘烤，曝光和显影，按制造商的建议。可用于光致抗蚀剂，如SPR，AZ或SC系列，可替代地，面板可以定义使用光致交联的聚合物，如SU8，PEGDA，或光致交联的PDMS。根据光致抗蚀剂，厚度，因此，纺丝速度，曝光时间和开发时间的选择将需要作相应的调整。 </li><li>光刻后，金属颗粒的大小取决于Cles的，厚的面板可以通过电沉积形成，而薄的面板，可以通过蒸发或溅射定义。 <ol><li>对于面板的电沉积，法拉第定律的电沉积和浴的效率，应使用来计算总的暴露表面面积的面板的基础上的电镀电流。典型的电流密度为镍（Ni）和焊料（Pb-Sn合金）镀层之间，分别为1-10毫安/厘米2和20-50毫安/厘米2。 </li></ol></li></ol> 5。图案的铰链类似面板的图案化，以图案铰链，第二轮的光刻法需要做使用铰链掩模（图2B-C）。的面板和铰链口罩的注册表上的标记需要被覆盖，以确保适当的对齐。 <ol><li>对于表面张力驱动组件，应选择这样的铰链材料具有低的材料的面板和铰链呃熔点比面板，因此面板保持刚性，而在铰链被熔化。大会发生的铰链材料的熔点以上时，模板被加热。例如，在与Ni板的金属粒子的情况下，我们电沉积Pb-Sn焊料上的铰链，它们融化于〜200℃，提示折叠。同样，在聚合物颗粒的SU8板的情况下，将聚己内酯铰链，它们聚集在〜58℃，27的过程中效果最好的铰链材料被固定在铰链区时，在回流过程中， 也就是说 ，它并不遍布面板和不完全dewet的面板。这可以通过以下来实现适当的润湿特性和粘度的材料选择与钉扎。 </li><li>在驱动自我折叠的薄膜应力的情况下，铰链应被图案化前面板构图。通常情况下，铰链需要组成的差异强调双层，的预应力金属如铬（Cr）或锆（Zr）和一个相对无应力的金属，如金（Au）或铜（Cu）组成。例如，对于用铰链的间隙为50μm的microgrippers，我们使用为50nm的Cr和100 nm的Au构成的双层。除了 ​​差异强调的金属双层，差异强调聚合物34-37，也可以使用氧化硅层38或5层外延半导体。 </li><li> ，自身折叠的薄膜应力，热敏感的聚合物触发层应该被用来限制设备，这样的结构不自发地折叠后释放的基板。适当的选择的触发材料和厚度可以赋予不同的刺激响应性的设备。例如，图案形成1.5微米厚的光致抗蚀剂（S1800系列）的铰链区是足够的保持装置的单位，直到它们被加热至〜37℃至触发折叠。 </li></ol><ol><li>要释放的图案化的2D模板，牺牲层需要由适当的蚀刻剂（图2d）被溶解。 </li><li>对于表面张力驱动组件，被释放的平面状的前体需要铰链材料的熔点以上的被加热物。在加热时，铰链的开始浏览液化并组装成适当形状的中空粒子（图2e-i）的前体。 </li><li>对于薄膜应力驱动折叠，折叠后，可以触发的结构，从基板和暴露在正确的刺激， 例如 ，在加热时被释放，使得触发软化并不再限制放宽应激双层铰链。由于把持装置是铁磁性的，他们可以引导和定位附近适当的货物和触发它周围折叠（图2j的正）。值得注意的是，组织EXCISION可以使用这种触发折叠25。 </li></ol>实施例1。议定书“表面张力驱动的自组装，永久接合，为300μm大小空心十二面（在图3中示意性表示）的制造： <ol><li>准备的掩模在步骤1中所解释的，对于与300μm的面板边缘长度的十二面体的制造，例如，正十二面体的五边形面板隔开30μm的一个绘制面板掩模。绘制折叠和密封铰链铰链的面具尺寸为240微米×60微米和240微米×30微米。 </li><li>准备的硅晶片基板，如在步骤2中说明。 </li><li>旋涂〜5.5微米厚的层A11 950聚甲基丙烯酸甲酯，以1,000 rpm，在硅晶片上。等待3分钟，然后在180℃下烘烤60秒。 </li><li>使用热蒸发器，沉积30nm的铬（Cr）作为粘合促进剂和150nm的铜（Cu）作为吨他导电层。 </li><li>旋涂〜10微米厚的SPR220在1700转时到晶圆上。等待3分钟。 </li><li>执行一个斜坡向上softbake的晶片放置在加热板上，在60℃，持续30秒。然后将其转移到另一个加热板的晶片在115℃下为90秒，然后返回到60℃，持续30秒。 </li><li>在室温下冷却该晶片并等待3小时。 </li><li>暴露在晶圆的面板使用〜460毫焦/厘米2的UV光（365nm）的和的汞为基础的掩模对准的掩模。 </li><li>发展中的MF-26A显影剂，持续2分钟，并改变显影剂溶液和发展另外2分钟。 </li><li>计算总的面板区域，并用它来 ​​计算所需的电流到电沉积镍从商业的氨基磺酸镍溶液中约1-10毫安/厘米2厚度为8μm的速率。 </li><li>的光致抗蚀剂溶解，用丙酮。用IPA冲洗晶片，并用N 2气干燥。 </li><li>旋涂〜10微米厚的SPR220在1700转时到晶圆上。等待3分钟。 </li><li>执行一个斜坡向上softbake的晶片放置在加热板上，在60℃，持续30秒。然后将其转移到另一个加热板的晶片在115℃下为90秒，然后返回到60℃，持续30秒。 </li><li>在室温下冷却该晶片并等待3小时。 </li><li>暴露在晶片到铰链使用〜460毫焦/厘米2的UV光（365nm）的和的汞为基础的掩模对准的掩模。确保该注册表标记对齐，使得铰链与面板对准。 </li><li>发展中的MF-26A显影剂，持续2分钟，并改变显影剂溶液和发展另外2分钟。 </li><li>使用金​​刚石切割器，切断成小片的晶片，使晶片中含有一块〜50-60网。指甲油件大衣的边缘。 </li><li>计算总的露出的铰链区域，并用它来计算所需的电流电沉积Pb-Sn焊料，从商业的焊料镀覆溶液在适当的速率ximately 20-50毫安/厘米2，厚度为15μm。 </li><li>的光致抗蚀剂溶解在丙酮中。晶片片用IPA冲洗，并用N 2气干燥。 </li><li>沉浸在25-40秒的蚀刻剂APS 100溶解周围的铜层的晶圆片。用DI水冲洗，并用N 2气干燥。 </li><li>沉浸在30-50秒的片晶圆蚀刻剂CRE-473溶解周围的铬层。用DI水冲洗，并用N 2气干燥。 </li><li>晶片浸入一块〜2-3毫升的1 - 甲基-2-Pyrollidinone（NMP）和热，在100℃下进行3-5分钟，直至模板从基材放出。 </li><li>传输〜20-30模板到一个小培养皿中，并均匀分配。 </li><li>加入3-5毫升NMP〜5-7滴Indalloy 5RMA液体助焊剂。 </li><li>热在100℃下进行5分钟。在此步骤中，的Indalloy 5RMA的液体助焊剂清洁和溶解任何氧化物层上形成焊料，从而可确保良好的焊料REFLOW加热至高于熔点。 </li><li>加热板的温度增加至150℃下进行5分钟，然后慢慢地增加至200℃，直至折叠发生。当温度升高到200°C的折叠5-8分钟后开始。该混合物会变成棕，因为它开始燃烧。 </li><li>当正十二面体折叠，使菜降温。丙酮的菜，移液管的液体，在丙酮中，然后用乙醇冲洗正十二面体。 </li><li>存储粒子在乙醇中的十二面体。 </li></ol>实施例2。议定书薄膜应力驱动自我折叠的热敏感microgrippers（在图4中示意性表示）的可重新配置的，制造： <ol><li>在步骤1中所解释的，准备口罩。设计掩模使的夹纱器的尖到尖的长度为980微米，与中央面板侧的111微米的长度和铰链的间隙为50μm。可以设计典型的铰链和面板口罩simil河图1的 。 </li><li>准备在步骤2中所解释的硅晶片。 </li><li>存款15 nm铬层附着力和50〜100 nm的铜牺牲层使用热蒸发器。 </li><li>旋涂〜3微米厚的S1827使用旋涂机，在3,000 rpm。等待3分钟，然后在115℃下进行1分钟的加热板上烘烤晶片。 </li><li>公开在〜180毫焦耳/厘米2的UV光（365nm）的使用的掩模对准器和铰链掩模。 </li><li>在5:1稀释351开发者开发为40-60秒。用DI水冲洗，并用N 2气干燥。 </li><li>存款50 nm铬层和100 nm的Au使用热蒸发器。的Cr-金用作铰链双层，在Cr膜中的残余应力，而Au膜是一种生物惰性的支撑层。 </li><li>在丙酮中的光致抗蚀剂剥离。使用超声发生器3-5分钟，以完全解除掉多余的金属。晶片洗净，用丙酮和IPA，干燥的N 2气体。 </li><li>旋涂〜10微米厚的SPR2201700转到晶片上。等待3分钟。 </li><li>执行一个斜坡向上softbake的晶片放置在加热板上，在60℃，持续30秒。然后将其转移到另一个加热板的晶片在115℃下为90秒，然后返回到60℃，持续30秒。等待3个小时。 </li><li>公开的光致抗蚀剂在约460毫焦耳/厘米2的UV光（365nm）的利用掩模对准装置通过面板掩模。 </li><li>发展中的MF-26A显影剂，持续2分钟，并改变显影剂溶液和发展另外2分钟。 </li><li>计算总的面板区域，并用它来 ​​计算所需的电流，以约1-10毫安/厘米2的厚度为5微米的速率从商业的氨基磺酸镍溶液中电沉积的Ni。用去离子水冲洗彻底。 </li><li>电沉积或蒸发100 nm的Au。该层有助于保护镍用来去除所述牺牲层的蚀刻剂。 </li><li>剥去丙酮的光致抗蚀剂。用IPA冲洗晶片，并用N 2气干燥。 </李&gt; <li>按1:5的体积比混合S1813和S1805 photoresits的。旋涂的混合物，在转速为1,800 rpm时。等待3分钟，然后在115℃下在加热板上烘烤1分钟。这种光致抗蚀剂层作为触发层。 </li><li>使用铰链的掩模的掩模对准器上在〜120毫焦耳/厘米2的UV光（365nm）的公开。 </li><li>在5:1稀释351开发人员开发30-50秒。用DI水冲洗，并用N 2气干燥。 </li><li>使用金​​刚石切割器的晶片切下一块。 </li><li>在APS 100的晶片浸入片进行蚀刻牺牲层，底层的Cu。等待直到的microgrippers完全从基材放出的。 </li><li>与去离子水，并存储在冷水中冲洗microgrippers。 </li><li>触发折叠放置在37°C水的microgrippers。 </li></ol> 7。代表性的成果有代表性的结果在图5示出了自组装的多面体粒子在各种的sh猿作为以及折叠microgrippers的。制造和驱动程序是高度并行的，可以制作的三维结构，并同时触发。此外，例如正方形或三角形的孔的精确的模式可以被定义在所有三个维度上，并且如果需要，选择的面。可封闭的microgrippers生物良性的条件下，使他们可以用于切除组织或加载与生物货物。此外，以来microgrippers可以由铁磁材料制成的，它们可以从远方移动使用磁场。 <img alt="图1" src="/files/ftp_upload/50022/50022fig1.jpg" /> 图1。图案化的粒子的合成的设计规则 （交流）的组件的图案化的多面体粒子面膜设计规则;面板掩模示意图（一），（二）示意性铰链罩设有折叠的边的长度L的多面体（0.2L×0.8升）和锁定或密封（0.1升×0.8升）的铰链，和（c）示意性的重叠2D前体或净。 （DF）面膜设计规则的自我折叠的微夹钳;（四）原理的铰链面具的微夹钳用尖头尖长度D，（E）原理与铰链间隙g的面板面膜，及（f）示意图重叠的二维前体。 <a href="https://www.jove.com/files/ftp_upload/50022/50022fig1large.jpg" target="_blank">点击此处查看大图</a> 。 <img alt="图2" src="/files/ftp_upload/50022/50022fig2.jpg" /> 图2。实验图像和动画概念的制造和装配过程中的重要步骤。（A）的屏幕截图的AutoCAD面板遮罩十二面体的前体。 （bc）条的光学图像的2D的前体，（二）正十二面体，和（c）在硅衬底上的microgrippers。 （四）公布的十二面体网。比例尺：200微米。 （EN）概念一nimation，（EI）的表面张力驱动的十二面体的组装，珠（JN）薄膜应力驱动的折叠周围的微夹钳（动画由大卫Filipiak）。 <img alt="图3" src="/files/ftp_upload/50022/50022fig3.jpg" /> 图3的立方颗粒的表面张力驱动组件的重要的制造步骤的示意图。 <img alt="图4" src="/files/ftp_upload/50022/50022fig4.jpg" /> 图4。驱动折叠的一个六位的把持装置的残余应力的重要的制造步骤的示意图。 <img alt="图5" src="/files/ftp_upload/50022/50022fig5.jpg" /> 图5。折纸灵感的自组装图案以及可重构的颗粒图像。 </强&gt;（一）自组装的粒子的光学图像中的各种不同的形状。 SEM图像（b）自组装多孔立方体（），（三）金字塔，（四）被截断八面体和（E）十二面体。比例尺：100微米。 （跳频）光学快照自我折叠microgrippers，和（i）的折叠微夹钳的SEM图像（图片由Timothy丰隆）。比例尺：200微米。

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G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabrication+and+applications+of+large+arrays+of+multifunctional+rolled-up+SiO/SiO2+microtubes.">Fabrication and applications of large arrays of multifunctional rolled-up SiO/SiO2 microtubes.</a> Journal of Materials Chemistry. 22, 2878-2884 (2012).</li><li>Randall, C. L., Kalinin, Y. V., Jamal, M., Shah, A., Gracias, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-folding+immunoprotective+cell+encapsulation+devices.">Self-folding immunoprotective cell encapsulation devices.</a> Nanomedicine. 7 (6), 686-689 (2011).</li><li>Kalinin, Y. V., Randhawa, J. S., Gracias, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three+dimensional+chemical+patterns+for+cellular+self-organization.">Three dimensional chemical patterns for cellular self-organization.</a> Angewandte Chemie. 50 (11), 2549-2553 (2011).</li><li>Randhawa, J. S., Keung, M. D., Tyagi, P., Gracias, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reversible+actuation+of+microstructures+by+surface+chemical+modification+of+thin+film+bilayers.">Reversible actuation of microstructures by surface chemical modification of thin film bilayers.</a> Advanced Materials. 22 (3), 407-410 (2010).</li><li>Bassik, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enzymatically+triggered+actuation+of+miniaturized+tools.">Enzymatically triggered actuation of miniaturized tools.</a> Journal of the American Chemical Society. 132, 16314-16317 (2010).</li></ol>

没有利益冲突的声明。

我们的折纸启发的组装过程是多用途的，可用于合成各种3D静态和可重构的范围广泛的材料，形状和尺寸的颗粒与。另外，精确地图案传感器和电子模块的这些颗粒的能力是重要的光学和电子学。这种方法以斑片状颗粒形成的替代方法，其中图案是相对不精确相反，提供了一种手段，合成精确图案化的颗粒。在基于表面张力的组件，液化密封铰链的使用确保颗粒以及密封和机械刚性组装后（冷却时）。在此之前，我们已经观察到的接缝防漏的小分子39,40。在装配后的Au层的薄的电沉积可以提供额外的强度和提高接缝的防漏性质。基于折叠的薄膜应力是有用的应用程序，其中圣是必需的，如在已被用于在体外和体内生物采样和在机器人的拾取和放置操作中执行的microgrippers imuli响应折叠。虽然这里所描述的具体方法，可以使用到建立可重构microgrippers，只关闭一次，选择适宜的材料和双层膜中的应力的方法来操作，可以利用，也建立把持器件，可通过重新配置在多个周期的37，41。这些设备的使用残余应力的亮点是，他们并不需要任何系绳或电线等具有良好的可操作性，使驱动难以到达的地方。另外，通过选择合适的聚合触发器，可以刺激响应行为的刺激的范围内，包括酶42启用自主功能相关的机器人和手术启动。

<table border="1"><tbody><tr><td> 的试剂的名称 </td><td> 公司 </td><td> 目录编号 </td><td> 评论 </td></tr><tr><td> 950聚甲基丙烯酸甲酯A11 </td><td>微型化学</td><td> M230011 </td><td>牺牲层</td></tr><tr><td>镀铬钨棒</td><td> RD马西斯公司</td><td> CRW-2 </td><td>蒸发源对Cr </td></tr><tr><td>铜鼻涕虫</td><td>阿法埃莎</td><td> 7440-50-8 </td><td>蒸发源铜</td></tr><tr><td>黄金蛞蝓</td><td>阿法埃莎</td><td> 7440-57-5 </td><td>蒸发源金</td></tr><tr><td> SPR 220 7.0 </td><td> Rohm and Haas公司</td><td> 10016640 </td><td>正光阻</td></tr><tr><td>小号1800系列的光致抗蚀剂</td><td>罗姆和哈斯</td><td></td><td>正Photoresist </td></tr><tr><td> Megaposit MF-26的开发人员</td><td> Rohm and Haas公司</td><td> 10016574 </td><td>为SPR 220 7.0光致抗蚀剂的开发人员</td></tr><tr><td>的Microposit 351开发</td><td>罗姆和哈斯</td><td> 10016653 </td><td>开发的S 1800系列的光致抗蚀剂</td></tr><tr><td>氨基磺酸镍</td><td>工艺公司</td><td> 030175 </td><td>对于Ni的电镀溶液</td></tr><tr><td>技术上的焊锡伴侣NF 820 60/40 RTU </td><td>工艺公司</td><td> 330681 </td><td>电镀液的Pb-Sn的铰链</td></tr><tr><td> APS 100铜蚀刻剂</td><td> Transene公司公司公司</td><td> 021221 </td><td>铜蚀刻剂</td></tr><tr><td> CRE 473铬蚀刻剂</td><td> Transene公司公司公司</td><td> 040901 </td><td>铬蚀刻剂</td></tr><tr><td> 1 - 甲基-2-Pyrollidinone（NMP） </td><td> Sigma-Aldrich公司</td><td>中号79603 </td><td>高沸点有机溶剂的Pb-Sn的铰链根据自我折叠</td></tr><tr><td> Indalloy 5RMA通量</td><td>美国铟泰公司</td><td> FL28372 </td><td>焊锡表面的化学物质，清除和抑制氧化，良好的Pb-Sn回流</td></tr></tbody></table>

origami inspired self-assembly of patterned and reconfigurable particles

有许多技术，如光刻，电子束光刻和软光刻技术，可用于精确地图案的二维（2D）结构。这些技术是成熟的，具有较高的精度，其中许多人在高通量的方式可以实现。我们利用平面的光刻技术的优点和将它们与自我折叠方法1-20来自表面张力或残余应力，其特征在于，物理力是三维（3D）结构用于曲线或折叠的平面结构的成。在这样做时，我们有可能大规模生产正是图案的静态和可重配置的粒子，具有挑战性的合成。 在本文中，我们详细的可视化实验的协议来创建图案的颗粒，值得注意的是，（一）永久地粘合，中空，多面体，自组装和自密封最大限度地减少液化铰链的表面能21-23及（b）夹持器，自倍由于残余应力供电铰链24,25。描述的特定的协议可以被用来建立与整体尺寸范围从微米到厘米的长度尺度颗粒。另外，任意的模式可以被定义的表面上的颗粒胶体科学，电子，光学和医学中的重要性。更一般地，与自密封铰链的自组装的机械刚性粒子的概念，是适用的，与某些过程的修改，在更小的颗粒的创建，100nm的长度尺度22，26和与范围的材料，包括金属21 ，半导体和聚合物27。我们的特定的协议使用对于残余应力供电可重构把持装置的致动，利用铬铰链的尺寸范围从100微米至2.5毫米的设备相关。然而，更一般地，这种系绳无残余应力的概念供电致动可用于如异质外延淀积的半导体膜5,7交替的高压力的材料，有可能创建更小纳米把持设备。

Watch this Scientific Journal Video about Origami Inspired Self-assembly of Patterned and Reconfigurable Particles at JoVE.com

Origami Inspired Self-assembly of Patterned and Reconfigurable Particles

我们描述的图案化和可重构的粒子从二维（2D）的前体的合成的实验细节。这个方法可以用于创建粒子的各种形状，包括多面体和把持装置在长度尺度范围从微至厘米级。

折纸灵感的图案和可重构颗粒自组装

There are numerous techniques such as photolithography, electron-beam lithography and soft-lithography that can be used to precisely pattern two ...

origami-inspired-self-assembly-patterned-reconfigurable

Research

JoVE Journal

Chemistry

21.5K 次观看.  The Johns Hopkins University. 我们描述的图案化和可重构的粒子从二维（2D）的前体的合成的实验细节。这个方法可以用于创建粒子的各种形状，包括多面体和把持装置在长度尺度范围从微至厘米级。

视频: Origami Inspired Self-assembly of Patterned and Reconfigurable Particles

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control self-assembly and mimicking this process in vitro will bring about major advances in the areas of materials science and nanotechnology. Among the available biological building blocks, peptides have several advantages as they present substantial diversity, their synthesis in large scale is straightforward, and they can easily be modified with biological and chemical entities1,2. Several classes of designed peptides such as cyclic peptides, amphiphile peptides and peptide-conjugates self-assemble into ordered structures in solution. Homoaromatic dipeptides, are a class of short self-assembled peptides that contain all the molecular information needed to form ordered structures such as nanotubes, spheres and fibrils3-8. A large variety of these peptides is commercially available.
This paper presents a procedure that leads to the formation of ordered structures by the self-assembly of homoaromatic peptides. The protocol requires only commercial reagents and basic laboratory equipment. In addition, the paper describes some of the methods available for the characterization of peptide-based assemblies. These methods include electron and atomic force microscopy and Fourier-Transform Infrared Spectroscopy (FT-IR). Moreover, the manuscript demonstrates the blending of peptides (coassembly) and the formation of a &#34;beads on a string&#34;-like structure by this process.9 The protocols presented here can be adapted to other classes of peptides or biological building blocks and can potentially lead to the discovery of new peptide-based structures and to better control of their assembly.

This paper describes the formation of highly ordered peptide-based structures by the spontaneous process of self-assembly. The method utilizes commercially available peptides and common lab equipment. This technique can be applied to a large variety of peptides and may lead to the discovery of new peptide-based assemblies.

生物分子有序结构由短肽的自组装形成

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control ...

科研

化学

Self-assembly of Complex Two-dimensional Shapes from Single-stranded DNA Tiles

Current methods in DNA nano-architecture have successfully engineered a variety of 2D and 3D structures using principles of self-assembly. In this article, we describe detailed protocols on how to fabricate sophisticated 2D shapes through the self-assembly of uniquely addressable single-stranded DNA tiles which act as molecular pixels on a molecular canvas. Each single-stranded tile (SST) is a 42-nucleotide DNA strand composed of four concatenated modular domains which bind to four neighbors during self-assembly. The molecular canvas is a rectangle structure self-assembled from SSTs. A prescribed complex 2D shape is formed by selecting the constituent molecular pixels (SSTs) from a 310-pixel molecular canvas and then subjecting the corresponding strands to one-pot annealing. Due to the modular nature of the SST approach we demonstrate the scalability, versatility and robustness of this method. Compared with alternative methods, the SST method enables a wider selection of information polymers and sequences through the use of de novo designed and synthesized short DNA strands.

DNA tiling is an effective approach to make programmable nanostructures. We describe the protocols to construct complex two-dimensional shapes by the self-assembly of single-stranded DNA tiles.

复杂的二维形状的从单链DNA的瓷砖自组装

Current methods in DNA nano-architecture have successfully engineered a variety of 2D and 3D structures using principles of self-assembly. In this ...

Preparation of Mica and Silicon Substrates for DNA Origami Analysis and Experimentation

The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of these applications require interaction with and adhesion of DNA nanostructures to a substrate. Due to its atomically flat and easily cleaned nature, mica has been the substrate of choice for DNA origami experiments. However, the practical applications of mica are relatively limited compared to those of semiconductor substrates. For this reason, a straightforward, stable, and repeatable process for DNA origami adhesion on derivatized silicon oxide is presented here. To promote the adhesion of DNA nanostructures to silicon oxide surface, a self-assembled monolayer of 3-aminopropyltriethoxysilane (APTES) is deposited from an aqueous solution that is compatible with many photoresists. The substrate must be cleaned of all organic and metal contaminants using Radio Corporation of America (RCA) cleaning processes and the native oxide layer must be etched to ensure a flat, functionalizable surface. Cleanrooms are equipped with facilities for silicon cleaning, however many components of DNA origami buffers and solutions are often not allowed in them due to contamination concerns. This manuscript describes the set-up and protocol for in-lab, small-scale silicon cleaning for researchers who do not have access to a cleanroom or would like to incorporate processes that could cause contamination of a cleanroom CMOS clean bench. Additionally, variables for regulating coverage are discussed and how to recognize and avoid common sample preparation problems is described.

Reproducible cleaning processes for substrates used in DNA origami research are described, including bench-top RCA cleaning and derivatization of silicon oxide. Protocols for surface preparation, DNA origami deposition, drying parameters, and simple experimental set-ups are illustrated.

对于DNA折纸分析和实验准备云母和硅衬底

The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of ...

Grafting Multiwalled Carbon Nanotubes with Polystyrene to Enable Self-Assembly and Anisotropic Patchiness

We demonstrate a straightforward protocol to graft pristine multiwalled carbon nanotubes (MWCNTs) with polystyrene (PS) chains at the sidewalls through a free-radical polymerization strategy to enable the modulation of the nanotube surface properties and produce supramolecular self-assembly of the nanostructures. First, a selective hydroxylation of the pristine nanotubes through a biphasic catalytically mediated oxidation reaction creates superficially distributed reactive sites at the sidewalls. The latter reactive sites are subsequently modified with methacrylic moieties using a silylated methacrylic precursor to create polymerizable sites. Those polymerizable groups can address further polymerization of styrene to produce a hybrid nanomaterial containing PS chains grafted to the nanotube sidewalls. The polymer-graft content, amount of silylated methacrylic moieties introduced and hydroxylation modification of the nanotubes are identified and quantified by Thermogravimetric Analysis (TGA). The presence of reactive functional groups hydroxyl and silylated methacrylate are confirmed by Fourier Transform Infrared Spectroscopy (FT-IR). Polystyrene-grafted carbon nanotube solutions in tetrahydrofuran (THF) provide wall-to-wall collinearly self-assembled nanotubes when cast samples are analyzed by transmission electron microscopy (TEM). Those self-assemblies are not obtained when suitable blanks are similarly cast from analogous solutions containing non-grafted counterparts. Therefore, this method enables the modification of the nanotube anisotropic patchiness at the sidewalls which results into spontaneous auto-organization at the nanoscale.

A procedure for the synthesis of polystyrene-grafted multiwalled carbon nanotubes using successive chemical modification steps to selectively introduce the polymer chains to the sidewalls and their self-assembly via anisotropic patchiness is presented.

用聚苯乙烯接枝多壁纳米碳纳米管使自组装和各向异性斑块

We demonstrate a straightforward protocol to graft pristine multiwalled carbon nanotubes (MWCNTs) with polystyrene (PS) chains at the sidewalls through a ...

Liquid-cell Transmission Electron Microscopy for Tracking Self-assembly of Nanoparticles

Drying a nanoparticle dispersion is a versatile way to create self-assembled structures of nanoparticles, but the mechanism of this process is not fully understood. We have traced the trajectories of individual nanoparticles using liquid-cell transmission electron microscopy (TEM) to investigate the mechanism of the assembly process. Herein, we present the protocols used for liquid-cell TEM studies of the self-assembly mechanism. First, we introduce the detailed synthetic protocols used to produce uniformly sized platinum and lead selenide nanoparticles. Next, we present the microfabrication processes used to produce liquid cells with silicon nitride or silicon windows and then describe the loading and imaging procedures of the liquid-cell TEM technique. Several notes are included to provide helpful tips for the entire process, including how to manage the fragile cell windows. The individual motions of nanoparticles tracked by liquid-cell TEM revealed that changes in the solvent boundaries caused by evaporation affected the self-assembly process of nanoparticles. The solvent boundaries drove nanoparticles to primarily form amorphous aggregates, followed by flattening of the aggregates to produce a 2-dimensional (2D) self-assembled structure. These behaviors are also observed for different nanoparticle types and different liquid-cell compositions.

Here we introduce experimental protocols for the real-time observation of a self-assembly process using liquid-cell transmission electron microscopy.

用于跟踪纳米粒子自组装的液体细胞透射电子显微镜

Drying a nanoparticle dispersion is a versatile way to create self-assembled structures of nanoparticles, but the mechanism of this process is not fully ...

Fabrication of Spherical and Worm-shaped Micellar Nanocrystals by Combining Electrospray, Self-assembly, and Solvent-based Structure Control

Micellar nanocrystals (micelles with encapsulated nanocrystals) have become an emerging major class of nanobiomaterials. We describe a method of fabricating micellar nanocrystals based on combining top-down electrospray, bottom-up self-assembly, and solvent-based structure control. This method involves first using electrospray to generate uniform ultrafine liquid droplets, each of which functions as a micro-reactor in which self-assembly reaction occurs forming micellar nanocrystals, with the structures (micelle shape and nanocrystal encapsulation) controlled by the organic solvent used. This method is largely continuous and produces high quality micellar nanocrystal products with an inexpensive structure control approach. By using a water-miscible organic solvent tetrahydrofuran (THF), worm-shaped micellar nanocrystals can be produced due to solvent-induced/facilitated micelle fusion. Compared with the common spherical micellar nanocrystals, worm-shaped micellar nanocrystals can offer minimized non-specific cellular uptake, thus enhancing biological targeting. By co-encapsulating multiple nanocrystals into each micelle, multifunctional or synergistic effects can be achieved. Current limitations of this fabrication method, which will be part of the future work, primarily include imperfect encapsulation in the micellar nanocrystal product and the incompletely continuous nature of the process.

The present work describes a method to fabricate micellar nanocrystals, an emerging major class of nanobiomaterials. This method combines top-down electrospray, bottom-up self-assembly, and solvent-based structure control. The fabrication method is largely continuous, can produce high quality products, and possesses an inexpensive means of structure control.

结合电喷雾、自组装和溶剂型结构控制制备球形和蜗杆状胶束纳米晶

Micellar nanocrystals (micelles with encapsulated nanocrystals) have become an emerging major class of nanobiomaterials. We describe a method of ...

Bio-inspired Polydopamine Surface Modification of Nanodiamonds and Its Reduction of Silver Nanoparticles

Surface functionalization of nanodiamonds (NDs) is still challenging due to the diversity of functional groups on the ND surfaces. Here, we demonstrate a simple protocol for the multifunctional surface modification of NDs by using mussel-inspired polydopamine (PDA) coating. In addition, the functional layer of PDA on NDs could serve as a reducing agent to synthesize and stabilize metal nanoparticles. Dopamine (DA) can self-polymerize and spontaneously form PDA layers on ND surfaces if the NDs and dopamine are simply mixed together. The thickness of a PDA layer is controlled by varying the concentration of DA. A typical result shows that a thickness of ~5 to ~15 nm of the PDA layer can be reached by adding 50 to 100 &#181;g/mL of DA to 100 nm ND suspensions. Furthermore, the PDA-NDs are used as a substrate to reduce metal ions, such as Ag[(NH3)2]+, to silver nanoparticles (AgNPs). The sizes of the AgNPs rely on the initial concentrations of Ag[(NH3)2]+. Along with an increase in the concentration of Ag[(NH3)2]+, the number of NPs increases, as well as the diameters of the NPs. In summary, this study not only presents a facile method for modifying the surfaces of NDs with PDA, but also demonstrates the enhanced functionality of NDs by anchoring various species of interest (such as AgNPs) for advanced applications.

A facile protocol is presented to functionalize the surfaces of nanodiamonds with polydopamine.

纳米金刚石的生物激发多巴胺表面改性及其对银纳米粒子的还原

Surface functionalization of nanodiamonds (NDs) is still challenging due to the diversity of functional groups on the ND surfaces. Here, we demonstrate a ...

Gene-therapy Inspired Polycation Coating for Protection of DNA Origami Nanostructures

DNA origami nanostructures hold an immense potential to be used for biological and medical applications. However, low-salt conditions and nucleases in physiological fluids induce denaturation and degradation of self-assembled DNA nanostructures. In non-viral gene delivery, enzymatic degradation of DNA is overcome by the encapsulation of the negatively charged DNA in a cationic shell. Herein, inspired by gene delivery advancements, a simple, one-step and robust methodology is presented for the stabilization of DNA origami nanostructures by coating them with chitosan and linear polyethyleneimine. The polycation coating efficiently protects DNA origami nanostructures in Mg-depleted and nuclease-rich media. This method also preserves the full addressability of enzyme- and aptamer-based functionalization of DNA nanostructures.

Here, a protocol for the protection of DNA origami nanostructures in Mg-depleted and nuclease-rich media using natural cationic polysaccharide chitosan and synthetic linear polyethyleneimine (LPEI) coatings is presented.

基因治疗诱导聚化涂层保护 dna 折纸纳米结构

DNA origami nanostructures hold an immense potential to be used for biological and medical applications. However, low-salt conditions and nucleases in ...

Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers

The production of monodisperse cylindrical micelles is a significant challenge in polymer chemistry. Most cylindrical constructs formed from diblock copolymers are produced by one of three techniques: thin film rehydration, solvent switching or polymerization-induced self-assembly, and produce only flexible, polydisperse cylinders. Crystallization-driven self-assembly (CDSA) is a method which can produce cylinders with these properties, by stabilizing structures of a lower curvature due to the formation of a crystalline core. However, the living polymerization techniques by which most core-forming blocks are formed are not trivial processes and the CDSA process may yield unsatisfactory results if carried out incorrectly. Here, the synthesis of cylindrical nanoparticles from simple reagents is shown. The drying and purification of reagents prior to a ring-opening polymerization of &#949;-caprolactone catalyzed by diphenyl phosphate is described. This polymer is then chain extended by methyl methacrylate (MMA) followed by N,N-dimethyl acrylamide (DMA) using reversible addition&#8722;fragmentation chain-transfer (RAFT) polymerization, affording a triblock copolymer that can undergo CDSA in ethanol. The living CDSA process is outlined, the results of which yield cylindrical nanoparticles up to 500 nm in length and a length dispersity as low as 1.05. It is anticipated that these protocols will allow others to produce cylindrical nanostructures and elevate the field of CDSA in the future.

Crystallization-driven self-assembly (CDSA) displays the unique ability to fabricate cylindrical nanostructures of narrow length distributions. The organocatalyzed ring-opening polymerization of &#949;-caprolactone and subsequent chain extensions of methyl methacrylate and N,N-dimethyl acrylamide are demonstrated. A living CDSA protocol that produces monodisperse cylinders up to 500 nm in length is outlined.

通过结晶驱动生物降解块共聚物的自组装合成单分散圆柱状纳米粒子

The production of monodisperse cylindrical micelles is a significant challenge in polymer chemistry. Most cylindrical constructs formed from diblock ...

DNA Origami-Mediated Substrate Nanopatterning of Inorganic Structures for Sensing Applications

Structural DNA nanotechnology provides a viable route for building from the bottom-up using DNA as construction material. The most common DNA nanofabrication technique is called DNA origami, and it allows high-throughput synthesis of accurate and highly versatile structures with nanometer-level precision. Here, it is shown how the spatial information of DNA origami can be transferred to metallic nanostructures by combining the bottom-up DNA origami with the conventionally used top-down lithography approaches. This allows fabrication of billions of tiny nanostructures in one step onto selected substrates. The method is demonstrated using bowtie DNA origami to create metallic bowtie-shaped antenna structures on silicon nitride or sapphire substrates. The method relies on the selective growth of a silicon oxide layer on top of the origami deposition substrate, thus resulting in a patterning mask for following lithographic steps. These nanostructure-equipped surfaces can be further used as molecular sensors (e.g., surface-enhanced Raman spectroscopy (SERS)) and in various other optical applications at the visible wavelength range owing to the small feature sizes (sub-10 nm). The technique can be extended to other materials through methodological modifications; therefore, the resulting optically active surfaces may find use in development of metamaterials and metasurfaces.

Here, we describe a protocol to create discrete and accurate inorganic nanostructures on substrates using DNA origami shapes as guiding templates. The method is demonstrated by creating plasmonic gold bowtie-shaped antennas on a transparent substrate (sapphire).