Name: three-dimensional printing of thermoplastic materials to create automated syringe pumps with feedback control for microfluidic applications
Uploaded: 2018-08-30T12:30:00.000+00:00
Duration: 9 min 8 s
Description: Watch this Scientific Journal Video about Three-dimensional Printing of Thermoplastic Materials to Create Automated Syringe Pumps with Feedback Control for Microfluidic Applications at JoVE.com

提交人承认来自海军研究奖 N00014-17-12306 和 N00014-15-1-2502 的支持, 以及来自空军科研奖 FA9550-13-1-0108 和国家科学基金会赠款1709238号的支助。

1. 注射器泵3级打印和组装
<ol><li>
准备和 3 d 打印注射器泵组件
	<ol>
<li>下载。STL 设计文件从本文的补充文件。 注: 有六。stl 文件, 标题为 "JoVE_Syringe_Clamp_10mL_Size"、"JoVE_Syringe_Platform"、"JoVE_Syringe_Plunger_Connectors"、"JoVE_Syringe_Pump_End_Stop. stl"、"JoVE_Syringe_Pump_Motor_Connector. stl" 和 "JoVE_Syringe_Pump_Traveler_"在补充文件中推. stl。这些文件对应于注射器泵的3维打印部件。</li>
		<li>通过在专用于转换的软件包中打开这些文件以进行打印。STL 模型文件到正在使用的 3 d 打印机的可执行指令集。确保使用适当的软件作为某些打印机需要专有软件, 而另一些则可以直接从。STL 文件。</li>
		<li>使用高品质的 3 d 打印机设置, 用丙烯腈丁二烯苯乙烯 (ABS) 打印塑料部件。如果使用其他常见的 3 d 印刷材料, 如聚乳酸 (PLA) 或其他热塑性弹性体, 确保所完成的机械性能 (如弹性、屈服强度) 与 ABS 相媲美。</li>
		<li>将打印部件从 3 d 打印机的打印平台中分离出来。从成品部件中取出打印的支撑结构。 注意: 支持结构是由用于转换的特定于打印机的软件设计的。STL 模型文件到 3 d 打印机的可执行指令集。支持材料的数量和结构可能因使用的软件而异。</li>
		<li>使用砂纸打磨任何粗糙的边缘, 平滑打印的组件。为达到最佳效果, 请使用砂粒大小约为220的砂纸。请确保所有组件在装配前都是平滑的。</li>
		<li>确保所有七个部件都已打印。 注: 这些部件已命名如下: (I) 马达连接器, (II) 旅行者推挤, (III) 末端中止, (IV) 注射器平台, (V) 注射器钳, (VI) 注射器柱塞男性连接器和 (七) 注射器柱塞女性连接器。图 2A中引用了每个组件的罗马数字。在材料表中找到了装配机械零件的详细清单。</li>
	</ol>
</li>
	<li>
组装注射器泵 (图 2)
	<ol>
<li>使用带有固定螺钉的马达轴 Z 轴柔性耦合器将步进电机固定在螺纹杆上。在继续之前, 请确保旋转步进电机轴驱动螺纹杆而不打滑。</li>
		<li>将注射器平台连接到马达连接器上, 将注射器平台的连接钉牢牢地按在马达连接器顶部的联接孔上。</li>
		<li>通过电机连接器将四 16 mm 螺钉固定在步进1.2.1 中, 将组装部件与步骤1.2.2 中的部件连接起来。</li>
		<li>将两个直线球轴承和一个0.8 毫米的六角螺母插入到位于旅行者推底的开口处。</li>
		<li>通过在旅行者推上的0.8 毫米六角螺母将马达接头上的螺纹杆对准。</li>
		<li>插入两个直线轴通过旅客推和电机连接器。</li>
		<li>将两个六角螺母放在电机连接件的六角空间中, 然后使用两个16毫米螺钉拧紧连接, 确保直线轴不动。</li>
		<li>将球轴承插入末端停止的中间开口。</li>
		<li>从步骤1.2.7 连接到已装配元件的端停止。</li>
		<li>将两个六角螺母放在末端停止片的六角空间中, 然后使用两个 16 mm 螺钉拧紧连接以将末端停止贴到组件上。</li>
		<li>使用两个钢锁螺母和两个 16 mm 螺钉将注射器柱塞女性连接件连接到旅行者推片上。</li>
		<li>将10毫升注射器放在泵的顶部。确保柱塞头与注射器柱塞女性连接件的缺口对齐, 注射器筒的顶部固定在电机接头的插槽中。</li>
		<li>插入注射器柱塞男性连接件进入注射器柱塞女性连接器。确保男性和女性部件之间有紧密的配合, 保证活塞到位。</li>
		<li>使用两个六角螺母和两个35毫米螺钉将注射器钳连接到注射器平台, 确保注射器筒固定在注射器钳的插槽中。</li>
	</ol>
</li>
</ol>2. 微流控装置的制备
<ol><li>
使用光刻法制造主模具 注: 在以前的文献12中可以找到详细介绍微流控器件制造主模的设计和制作过程。<ol>
<li>使用首选计算机辅助设计 (CAD) 软件, 为光掩模创建所需的绘图, 并将其打印到玻璃或石英板上。 注: 其他材料可根据所用掩模光刻的要求接受。这些光掩膜的打印通常由第三方供应商完成。</li>
		<li>使用光刻方法从光掩模创建主模具。在洁净室环境中执行此过程。</li>
		<li>将制造的主模暴露在真空干燥中的 fluorosilane 蒸气中。 注: 此过程便于在制造微流控器件时从主模中释放烷 ()。要处理主模具, 在烧杯中加入三滴 fluorosilane, 将烧杯放在真空室中。</li>
		<li>应用真空1分钟关闭真空室, 但保持主模具在会议厅内30分钟, 以允许沉积的 fluorosilane。作为安全预防措施, 在通风罩中执行此步骤, 以限制暴露于危险的 fluorosilane 蒸气。</li>
	</ol>
</li>
	<li>
制造聚甲基硅器件
	<ol>
<li>称重船中的聚合物预聚合体。尽管最终的所需厚度可能有所不同, 但30克的预聚合物工作良好的主模具直径为100毫米。</li>
		<li>测量和添加一个固化剂在1:10 的比例对预聚合物。对于直径为100毫米的主模具, 添加3克固化剂。</li>
		<li>使用一次性刮刀, 用手大力搅拌预聚合剂和固化剂。三十年代后, 检查溶液中是否有小的、定期分离的气泡, 表明预聚合剂和固化剂的混合良好。</li>
		<li>将主模具放在培养板上, 并小心地将其混合在主模具上。 注: 所需的聚硅烷设备的厚度可能因其应用而异。</li>
		<li>将混合物在真空干燥中加成1小时. 确保在混合物中没有可见气泡。如果存在气泡, 请快速释放真空压力, 然后重新应用真空。在这个过程之后, 允许混合物至少坐10分钟。</li>
		<li>将该混合料移动到90摄氏度的烤箱。允许混合物治疗30分钟。</li>
		<li>从主模具中取出。用剃刀刀片将其切成所需尺寸。戴上手套以限制其接触污染物。</li>
		<li>带23克配药针的入口和出口端口的冲孔孔。为方便这一过程, 用金属锉或砂纸将针头锉削, 以锐化钝端。确保每次穿刺后, 从针头中取出的内壁圆筒。 注: 不同尺寸的针头可用于冲孔。确保大小比本协议步骤3中使用的针头稍大。</li>
		<li>使用装有0.2 µm 过滤器的空气或氮气源, 用过滤过的去离子水和空气干燥的方法清洗该硅烷。 注: 确切的压力并不重要, 从建筑物中央系统得到的加压气体源对这一步骤很有效。</li>
		<li>用表面活性剂 (如粉状洗涤剂) 清洁1号硼硅酸盐盖玻璃基板, 并使用装有0.2 µm 过滤器的加压空气源将其风干。彻底清洁, 因为盖玻璃经常涂有疏水性润滑剂, 不能绑定到, 除非它是正确的清洁。</li>
		<li>使用压敏胶带, 轻轻触碰所用的硅烷, 除去残余灰尘。为确保模压功能不受损, 请勿按下磁带上的大量力。</li>
		<li>将该设备和清洁后的盖玻璃放入氧气等离子清洗器中1分钟. 确保从等离子清洗室的颜色是明亮的洋红在过程中。确保在等离子清洗器中, 该设备的模压特性暴露在表面, 正面朝上。</li>
		<li>从等离子清洗机中拿出该产品和盖玻璃, 然后将盖子玻璃, 面朝下, 放到该装置上。 注: 这将导致盖板玻璃和在几乎立即债券。如果绑定不可见, 请轻轻按下盖玻璃, 在一个没有模压功能的部分。这将导致在与玻璃之间的粘结发生。</li>
		<li>将该设备放入烤箱中90摄氏度, 至少12小时, 以确保其和盖玻璃的粘合良好。</li>
	</ol>
</li>
</ol>3. 反馈控制注射器泵系统总成
<ol><li>使用剃刀从压力传感器的电缆中取出适当量的电线绝缘长度和屏蔽。在切割时要保持柔和, 以确保导线不超过所需长度。一旦绝缘和屏蔽被删除, 连接到男性矩形连接线。</li>
	<li>使用类似的方法上一步, 删除 1-2 cm 的电线绝缘从步进电机的引线, 并连接到男性矩形连接线。</li>
	<li>将注射器贴到压力传感器的入口侧。将22克配药针连接到压力传感器的出口侧。</li>
	<li>将0.51 厘米直径油管的一端滑动到压力传感器所附的22克配药针上。</li>
	<li>将0.51 厘米直径油管的另一端滑动至22克, 可连接到微流控装置上。将针头连接到微流控装置的入口端。</li>
	<li>使用22克针和0.51 厘米直径油管将微流控装置的出口端口连接到废物处理水库, 类似于入口口的连接。</li>
	<li>根据图 3中的图, 在原型案板上装配电子电路。 注: 此案板用于条件由单片机监视压力传感器的信号。其他兼容的微控制器可用于监测压力传感器信号。</li>
	<li>将步进电机的导线与步进电机驱动程序连接起来。根据图 3中的示意图, 将压力传感器和步进电机驱动程序的导线与案板连接。压力传感器暴露的导线是彩色编码的, 应按如下方式连接: 红色应该连接到 v +, 黑色应该连接到 v-, 绿色应该连接到信号 +, 白色应该连接到信号-。</li>
	<li>将输出信号从案板连接到单片机上的模拟输入销。</li>
	<li>将步进电机驱动程序的逻辑输入针脚与单片机上的数字针脚连接起来。步进电机驱动器上的步长输入与单片机上的数字引脚脉宽调制 (PWM) 端口连接, 用 "~" 符号表示。</li>
	<li>根据图 3中的图, 将电源与案板连接。将电源设置为案板和步进电机驱动程序的 10 V。</li>
</ol>4. 压力传感器校准
注: 根据本文所选择的放大器, 计算增益的公式为 g = 5 + (200 k/Rg), Rg = R1 和 g = 放大器增益。放大器增益在这里大约是606。通过更改用于 R1 的电阻, 可以更改此值。此外, 由于单片机电路板的逻辑电平为 5 v, 仪器为 10 v, 一个简单的分压器电路, R2 和 R3, 用于保证输出信号不超过 5 v。
<ol><li>为微控制器下载并安装适当的集成开发环境 (IDE)。</li>
	<li>从补充文件下载标题为 "Pressure_Sensing" 的控制器代码。使用此代码是从双压力传感器获取压力信号。 注: 本文使用的单片机和控制器代码包括10位分辨率的模拟输入销, 它每200毫秒读取来自压力传感器的模拟信号, 以驱动步进电机。analogRead () 托架中的数字对应于图 3中压力传感器电路中的电压分频器电路上与输出信号相连的模拟输入销。延迟变量表示在 ms 中对信号进行重新评估的间隔和相应的输出。</li>
	<li>将已知压力应用于传感器的入口, 并测量输出信号。 注: 一种简单的校准压力传感器的方法是使用带有不同高度的水油藏。由此产生的引力压力将允许一个校准压力传感器。</li>
	<li>在 x 轴和 y 轴上的压力信号 (V) 上绘制带有校准压力 (Pa) 的图, 以获得 y 截距的数值。</li>
	<li>在控制器代码中应用此数值, 如 sensor1Offset 和 sensor2Offset 变量在 "Dual_Pump_PID_Control" 的补充文件代码中, 以校准反馈控制系统中的压力值。</li>
</ol>5. 从微流控装置捕获图像
<ol><li>通过串行接口将微控制器连接到开放源码的单板计算机上, 以便由微型计算机捕获的图像触发微控制器所采取的压力测量。</li>
	<li>将用于单板计算机的照相机模块连接到显微镜的一个眼件。在这里, 20X 放大器用于图像微流控设备。</li>
</ol>6. 控制注射器压力泵
<ol><li>打开 IDE 以打开源代码微控制器。下载计时器. h13和 AccelStepper14库到微控制器的 IDE 库目录。</li>
	<li>从补充文件下载标题为 "Dual_Pump_PID_Control" 的控制器代码。该编码用于控制带有两个泵的反馈控制的注射器泵系统。</li>
	<li>对控制器代码进行编程, 使其符合正在进行的实验。修改控制参数或定时参数, 以适应实验所需的响应和持续时间。在运行实验之前, 将代码编译并上载到微控制器。 注: 在控制器代码中, setPoint1/2 值用于改变压力电平, stepper1/2Out 值用于调整泵的速度。AccelStepper stepper1/2 列中的最后两个值对应于微控制器上的端口号。milliTiming 变量规定了从压力传感器读取模拟信号的频率, 而 printTiming 变量决定了输出速度和压力值到串行显示器进行检测的频率。所有单位都在 ms. maxError 变量是由单片机板的逻辑电平确定的。这里使用的值为 5, 因为该协议中的微控制器为 5 v。</li>
	<li>打开注射器泵系统的电源。将电压设置为 10 V, 以便步进电机供电。</li>
</ol>7. 调节 PID 控制器参数
注意: 理想的控制器参数值可能因应用程序和微流控设备几何图形而异。例如, 对于长期研究 (小时), 较低比例常数 (Kp) 可能更可取, 以减少超调, 以牺牲响应时间。这些权衡取决于实验条件和目标。
<ol><li>使用手动方法调整控制器, 首先调整比例常数 (Kp), 以提高步长函数的响应时间。 注意: 尽管可以使用算法方法, 但本文所示的微流控应用程序的手动调整工作。</li>
	<li>接下来, 改变积分 (基) 和微分 (Kd) 参数, 以最小化超调, 并确保设置点稳定性。</li>
	<li>在补充文件的控制器代码中设置 Kp、基和 Kd 变量的 PID 值。</li>
</ol>

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C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low-cost+feedback-controlled+syringe+pressure+pumps+for+microfluidics+applications.">Low-cost feedback-controlled syringe pressure pumps for microfluidics applications.</a> PLoS One. 12 (4), (2017).</li><li>Kong, D. S., 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=Open-source,+community-driven+microfluidics+with+metafluidics.">Open-source, community-driven microfluidics with metafluidics.</a> Nature Biotechnology. 35 (6), 523-529 (2017).</li><li>Wijnen, B., Hunt, E. J., Anzalone, G. C., Pearce, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Open-source+syringe+pump+library.">Open-source syringe pump library.</a> PLoS One. 9 (9), e107216 (2014).</li><li>Ferry, M. S., Razinkov, I. A., Hasty, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidics+for+synthetic+biology:+from+design+to+execution.">Microfluidics for synthetic biology: from design to execution.</a> Methods in Enzymology. , 295-372 (2011).</li><li>. Arduino Libraries for Timer.h Available from: <a target="_blank" href="https://github.com/JChristensen/Timer">https://github.com/JChristensen/Timer</a> (2018)</li><li>. Arduino Libraries for AccelStepper.h Available from: <a target="_blank" href="https://github.com/adafruit/AccelStepper">https://github.com/adafruit/AccelStepper</a> (2018)</li><li>Lin, F., 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=Generation+of+dynamic+temporal+and+spatial+concentration+gradients+using+microfluidic+devices.">Generation of dynamic temporal and spatial concentration gradients using microfluidic devices.</a> Lab on a Chip. 4 (3), 164-167 (2004).</li><li>Korczyk, P. 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作者没有什么可透露的。

在这里, 我们提出了一个新的设计的注射器泵系统的闭环压力控制。这是通过集成一个 3 d-打印注射器泵与压阻式压力传感器和开放源码微控制器。通过采用 PID 控制器, 能够精确控制进气压力, 提供快速响应时间, 同时保持设定点的稳定性。
许多使用微流控器件的实验都需要精确的射流控制, 并能开发出具有良好特征的层流剖面。一个稳定的流量剖面很重要的例子包括探索时间和空间浓度梯度15的实验, 并产生精确的射流胶囊进一步分析16.通过使用 PID 控制器来保持高性能响应, 本协议中描述的系统产生了研究这种层流实验所需的流量调节和长期稳定性。
然而, 重要的是要认识到, 微流控装置和实验涉及他们有微妙的变化和差异。例如, 不同的微流控几何 (通道宽度和高度) 可能需要不同的流剖面。因此, 必须相应地调整 PID 控制器的参数。此外, 一些实验可能需要严格调节压力范围。在这些情况下, 压力超调可能是不能接受的。因此, 必须调整 PID 控制参数, 使超调降到最小, 通常是以牺牲响应时间为代价的。
由于这种注射器泵系统的低成本生产, 研究人员应该能够迅速发展微流控实验。3 d 打印的注射器泵、单片机和压力传感器电路的估计成本约为130美元。与商用的替代品, 如蠕动和回流泵相比, 这种注射器泵系统提供了一个灵活和直接的平台, 可适应各种实验室使用。虽然这里没有讨论, 但更简单的控制策略, 如砰砰的控制器, 可用于长期微流控研究。此外, 注射器泵系统可用于对控制容积施加真空压力。
这个注射器泵系统的一个潜在的限制使用 PID 控制器是依赖于恒定的电源。由于 PID 控制方法需要步进电机的恒通电, 因此有较大的功率要求。相比之下, 砰砰的控制器只在必要时给步进电机供电, 使用的功率大大降低。通过开发一种混合控制结构, 实现 PID 控制器初始达到设定点范围, 然后在给定的集点范围内对步进电机线圈进行能量消除, 从而可以减轻这种功耗要求。另外, 还可以使用一个简单的霹雳棒控制器。
此外, 这种注射器泵系统允许灵活的性能和控制, 改变的大小, 步进电机和注射器本身。在以前的实验中, 我们使用了1毫升、5毫升、10毫升和30毫升的注射器。当然, 每个注射器泵可能需要略有不同的 PID 控制器参数, 因此, 要求个性化参数调整。然而, 这种灵活性使得本协议中所描述的注射器泵系统可以在一系列应用中使用。
应该指出的是, microdevice 失败的一个共同领域是无法有效地将该硅烷与盖玻璃结合起来。对于微流控器件的制备, 如果结合效果不佳, 应优化等离子体清洗器的功率。此外, 任何润滑剂或杂质的封面玻璃 ' 的表面上应删除之前的粘合, 以确保与该板的强粘结。彻底清洗和清除来自该组件的任何灰尘, 将有助于确保在两个玻璃之间形成良好的密封。
本文介绍的低成本、反馈控制的注射器泵系统允许研究人员以灵活的方式操作具有高度稳定性的流体剖面。该系统通过将压力传感模块与简单的 PID 控制方法相结合, 能够提供高性能的压力驱动流量控制。此工具可以广泛应用于许多研究领域, 其中微流体工具正在使用中。

微流控工具已成为科学家在生物和化学研究的有用。由于体积利用率低, 快速测量能力和明确的流量剖面, 微流体在基因组和蛋白质研究、高通量筛选、医学诊断、纳米技术和单细胞分析1,2,3,4。此外, 微流控装置设计的灵活性容易使基础科学研究, 如调查细菌菌落的时空动态5。
许多类型的流体喷射系统已经开发, 以准确地提供流到微流控设备。这种喷射系统的例子包括蠕动和循环泵6、压力控制器系统7和注射器泵8。这些注射系统, 包括注射器泵, 通常由昂贵的精密工程部件组成。通过闭环反馈控制输出流中的压力, 增加这些系统的成本。作为回应, 我们以前开发了一个健壮的, 低成本的注射器泵系统, 使用闭环反馈控制, 以调节输出流量压力。采用闭环压力控制, 对昂贵的精密工程部件的需求被废止9。
可负担得起的 3 d 打印硬件和相关开源软件的显著增长组合使得微流控设备的设计和制造越来越多地从各种学科10的研究人员那里获得。然而, 用于通过这些设备驱动流体的系统仍然很昂贵。为了满足对低成本流体控制系统的需求, 我们开发了一个可以由实验室的研究人员制作的设计, 只需要少量的装配步骤。尽管它的成本低且简单, 但该系统可以提供精确的流量控制, 并提供了一种替代商用, 闭环注射器泵系统, 这可能是令人望而却步的昂贵。
在这里, 我们为我们开发的闭环控制注射器泵系统的建造和使用提供了协议 (图 1)。流体处理系统由以前的研究11、单片机和压阻式压力传感器所启发的物理注射器泵组成。当用比例积分-导数 (PID) 控制器组装和编程时, 系统能够向微流控装置提供良好的受控压力驱动流。这为高成本商业产品提供了低成本和灵活的替代方案, 使更广泛的研究人员能够在工作中使用微流体。

<table><tbody><tr><td>Arduino IDE</td><td>Arduino.org</td><td></td><td>Arduino Uno R3 control software</td></tr><tr><td>Header Connector, 2 Positions</td><td>Digi-Key</td><td>WM4000-ND</td><td></td></tr><tr><td>Header Connector, 3 Positions</td><td>Digi-Key</td><td>WM4001-ND</td><td></td></tr><tr><td>Header Connector, 4 Positions</td><td>Digi-Key</td><td>WM4002-ND</td><td></td></tr><tr><td>Hook-up Wire, 22 Gauge, Black</td><td>Digi-Key</td><td>1528-1752-ND</td><td></td></tr><tr><td>Hook-up Wire, 22 Gauge, Blue</td><td>Digi-Key</td><td>1528-1757-ND</td><td></td></tr><tr><td>Hook-up Wire, 22 Gauge, Red</td><td>Digi-Key</td><td>1528-1750-ND</td><td></td></tr><tr><td>Hook-up Wire, 22 Gauge, White</td><td>Digi-Key</td><td>1528-1768-ND</td><td></td></tr><tr><td>Hook-up Wire, 22 Gauge, Yellow</td><td>Digi-Key</td><td>1528-1751-ND</td><td></td></tr><tr><td>Instrumentation Amplifier</td><td>Texas Instruments</td><td>INA122P</td><td></td></tr><tr><td>Microcontroller, Arduino Uno R3</td><td>Arduino.org</td><td>A000066</td><td></td></tr><tr><td>Mini Breadboard</td><td>Amazon</td><td>B01IMS0II0</td><td></td></tr><tr><td>Power Supply</td><td>BK Precision</td><td>1550</td><td></td></tr><tr><td>Pressure Sensor</td><td>PendoTech</td><td>PRESS-S-000</td><td></td></tr><tr><td>Rectangular Connectors, Housings</td><td>Digi-Key</td><td>WM2802-ND</td><td></td></tr><tr><td>Rectangular Connectors, Male</td><td>Digi-Key</td><td>WM2565CT-ND</td><td></td></tr><tr><td>Resistors, 10k Ohm&amp;nbsp;</td><td>Digi-Key</td><td>1135-1174-1-ND</td><td></td></tr><tr><td>Resistors, 330 Ohm&amp;nbsp;</td><td>Digi-Key</td><td>330ADCT-ND</td><td></td></tr><tr><td>Stepper Motor Driver, EasyDriver</td><td>Digi-Key</td><td>1568-1108-ND</td><td></td></tr><tr><td>USB 2.0 Cable, A-Male to B-Male</td><td>Amazon</td><td>PC045</td><td></td></tr><tr><td>3D Printed Material, Z-ABS&amp;nbsp;</td><td>Zortrax</td><td></td><td>A variety of colors are available</td></tr><tr><td>3D Printer</td><td>Zortrax</td><td>M200</td><td>Printing out the syringe pump components</td></tr><tr><td>Ball Bearing, 17x6x6mm</td><td>Amazon</td><td>B008X18NWK</td><td></td></tr><tr><td>Hex Machine Screws, M3x16mm&amp;nbsp;</td><td>Amazon</td><td>B00W97MTII</td><td></td></tr><tr><td>Hex Machine Screws, M3x35mm&amp;nbsp;</td><td>Amazon</td><td>B00W97N2UW</td><td></td></tr><tr><td>Hex Nut, M3 0.5&amp;nbsp;</td><td>Amazon</td><td>B012U6PKMO</td><td></td></tr><tr><td>Hex Nut, M5&amp;nbsp;</td><td>Amazon</td><td>B012T3C8YQ</td><td></td></tr><tr><td>Lathe Round Rod</td><td>Amazon</td><td>B00AUB73HW</td><td></td></tr><tr><td>Linear Ball Bearing</td><td>Amazon</td><td>B01IDKG1WO</td><td></td></tr><tr><td>Linear Flexible Coupler</td><td>Amazon</td><td>B010MZ8SQU</td><td></td></tr><tr><td>Steel Lock Nut, M3 0.5</td><td>Amazon</td><td>B000NBKLOQ</td><td></td></tr><tr><td>Stepper Motor, NEMA-17, 1.8o/step</td><td>Digi-Key</td><td>1568-1105-ND</td><td></td></tr><tr><td>Syringe, 10mL, Luer-Lok Tip</td><td>BD</td><td>309604</td><td></td></tr><tr><td>Threaded Rod</td><td>Amazon</td><td>B01MA5XREY</td><td></td></tr><tr><td>1H,1H,2H,2H-Perfluorooctyltrichlorosilane</td><td>FisherScientific</td><td>AAL1660609</td><td></td></tr><tr><td>Camera Module</td><td>Raspberry Pi Foundation</td><td>V2</td><td></td></tr><tr><td>Compact Oven</td><td>FisherScientific</td><td>PR305220G</td><td>Baking PDMS pre-polymer mixture and the device</td></tr><tr><td>Dispensing Needle, 22 Gauge</td><td>McMaster-Carr</td><td>75165A682</td><td></td></tr><tr><td>Dispensing Needle, 23 Gauge</td><td>McMaster-Carr</td><td>75165A684</td><td></td></tr><tr><td>Fisherbrand Premium Cover Glasses</td><td>FisherScientific</td><td>12-548-5C</td><td></td></tr><tr><td>Glass Culture Petri Dish, 130x25mm</td><td>American Educational Products</td><td>7-1500-5</td><td></td></tr><tr><td>Plasma Cleaner</td><td>Harrick Plasma</td><td>PDC-32G</td><td>Binding the cover glass with the PDMS device</td></tr><tr><td>Razor Blades</td><td>FisherScientific</td><td>7071A141&amp;nbsp;</td><td></td></tr><tr><td>Scotch Magic Tape</td><td>Amazon</td><td>B00RB1YAL6</td><td></td></tr><tr><td>Single-board Computer</td><td>Raspberry Pi Foundation</td><td>Raspberry Pi 2 model B</td><td></td></tr><tr><td>Smart Spatula</td><td>FisherScientific</td><td>EW-06265-12</td><td></td></tr><tr><td>Sylgard 184 Silicone Elastomer Kit</td><td>FisherScientific</td><td>NC9644388</td><td></td></tr><tr><td>Syringe Filters</td><td>Thermo Scientific</td><td>7252520</td><td></td></tr><tr><td>Tygon Tubing</td><td>ColeParmer&amp;nbsp;</td><td>EW-06419-01</td><td></td></tr><tr><td>Vacuum Desiccator</td><td>FisherScientific</td><td>08-594-15C</td><td>Degasing PDMS pre-polymer mixture and coating fluorosilane on the master mold</td></tr><tr><td>Weighing Dishes</td><td>FisherScientific</td><td>S67090A</td><td></td></tr></tbody></table>

three-dimensional printing of thermoplastic materials to create automated syringe pumps with feedback control for microfluidic applications

微流体已成为研究跨生物、化学和物理科学的重要工具。微流控实验的一个重要组成部分是稳定的流体处理系统, 能够准确地提供进水流速率或进气压力。在这里, 我们开发了一种注射器泵系统, 能够控制和调节输送到微流控装置的入口流体压力。该系统的设计采用低成本材料和添加剂制造原则, 利用三维 (3D) 印刷热塑性材料和现成的组件, 只要可能的话。该系统由三主要部件组成: 注射器泵、压力传感器和可编程微控制器。在本文中, 我们详细介绍了一组用于制造、装配和编程这个注射器泵系统的协议。此外, 我们还包括了具有代表性的结果, 证明了高保真度, 反馈控制的入口压力使用这个系统。我们预计这项协议将允许研究人员制造低成本的注射器泵系统, 降低在生物医学、化学和材料研究中使用微流体的进入屏障。

在这里, 我们提出了一个建立一个反馈控制的注射器泵系统的协议, 并展示了它的潜在用途的微流控应用。图 1显示了注射器泵、压力传感器、微流控装置、单片机、压力传感器电路和步进电机驱动程序的连接系统。注射器泵总成的详细标注见图 2 , 压力传感电子电路示意图载于图 3。调整控制参数的过程如图 4所示。最后, 在两进制 Y 形微流控装置中控制进气压力的一个典型结果如图 5所示。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/57532/57532fig1.jpg"> 图 1: 设置反馈控制的注射器泵系统.该图像显示了注射器泵系统的设置。注射器含有注射液, 由 3 d-打印的注射器泵驱动。作为.压阻式压力传感器与B 连接.注射器泵和C.微流控装置, 检测到设备的压力, 并将其转换成电信号到D.压力传感器电路与仪表放大器一旦液体通过油管交付。来自压力传感器的信号由E 读取.开源微控制器板, 然后将所需信号传送到F.步进电机驱动控制注射器泵的驱动。G.电源和H.需要一台笔记本电脑来操作和编程系统。<a href="/files/ftp_upload/57532/57532fig1large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/57532/57532fig2.jpg"> 图 2: 3 d-打印注射器泵的装配照片.此图显示了 3 d 打印的注射器泵组件的分步说明, 其中的照片与该协议步骤1.2 中的步骤相对应。这个图像显示了注射器泵总成的材料。这张图片显示了步进电机是如何连接到螺纹杆 (步骤 1.2.1)。C.此图像显示了协议的步骤1.2.1 中的部件是如何从协议的步骤 1.2.2 (步骤 1.2.3) 连接到部件的。这个图像显示了旅行者推片的装配 (步骤 1.2.5)。E.此图像显示停止连接的方式 (步骤 1.2.10)。F.此图像显示了注射器柱塞女性连接件如何连接到组装部件 (步骤 1.2.11)。这个图像显示了注射器柱塞男性连接件 (步骤 1.2.13) 的装配。H.此图像显示了如何连接注射器钳 (步骤 1.2.14)。<a href="/files/ftp_upload/57532/57532fig2large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/57532/57532fig3.jpg"> 图 3: 单片机和压力传感器电路的插图.该电路允许单片机板测量压力传感器的放大压力信号。这是电路的装配图。这个数字显示电路板的布局。压力传感器暴露的导线是彩色编码的, 应按如下方式连接: 红色应该连接到 v +, 黑色应该连接到 v-, 绿色应该连接到信号 +, 白色应该连接到信号-。<a href="/files/ftp_upload/57532/57532fig3large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/57532/57532fig4.jpg"> 图 4: 控制参数的调整.用于调节注射器泵流体压力的 PID 控制器可以通过修改比例 (Kp)、积分 (基) 和微分 (Kd) 参数来调整。在这里, 我们演示如何调整 (使用 Kp) 将有助于减少响应时间。进一步调谐 (使用基和 Kd) 可以帮助确保设定的稳定性和减少超调。在本协议中, 控制器主要使用手动的试错方法进行调整。<a href="/files/ftp_upload/57532/57532fig4large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/57532/57532fig5.jpg"> 图 5: 层流流体微流控装置进气压力的控制.Y 形微流控装置是根据本协议步骤2中详细说明的步骤制作的。该设备具有两个入口端口和一个出口端口。两个注射器泵系统组装, 以控制进口压力。其中一个注射器装有蓝色染料, 另一只装有水。这两种泵所提供的相同压力所产生的流体流动的图像是使用本议定书步骤6中详细说明的方法捕获的.这个数字显示了如何使用图 4中调谐的 PID 控制器监控和控制进气压力。可以观察到设定点的紧密附着。较短的和更长的 (h) 实验表明了类似的结果。<a href="/files/ftp_upload/57532/57532fig5large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>

Watch this Scientific Journal Video about Three-dimensional Printing of Thermoplastic Materials to Create Automated Syringe Pumps with Feedback Control for Microfluidic Applications at JoVE.com

Three-dimensional Printing of Thermoplastic Materials to Create Automated Syringe Pumps with Feedback Control for Microfluidic Applications

在这里, 我们提出了一个协议, 建立一个压力控制注射器泵用于微流控应用。这种注射器泵是由一个加法制造的身体, 现成的硬件, 和开源电子。由此产生的系统成本低廉, 容易建立, 并提供良好的调节流体流动, 使快速微流控研究。

三维热塑性材料的印刷, 以创建自动注射器泵的反馈控制微流控应用

Microfluidics has become a critical tool in research across the biological, chemical, and physical sciences. One important component of microfluidic ...

three-dimensional-printing-thermoplastic-materials-to-create

Universidad San Sebastian

Research

JoVE Journal

Bioengineering

12.3K 次观看.  University of Pittsburgh. 在这里, 我们提出了一个协议, 建立一个压力控制注射器泵用于微流控应用。这种注射器泵是由一个加法制造的身体, 现成的硬件, 和开源电子。由此产生的系统成本低廉, 容易建立, 并提供良好的调节流体流动, 使快速微流控研究。

视频: Three-dimensional Printing of Thermoplastic Materials to Create Automated Syringe Pumps with Feedback Control for Microfluidic Applications

Manufacturing of Three-dimensionally Microstructured Nanocomposites through Microfluidic Infiltration

Microstructured composite beams reinforced with complex three-dimensionally (3D) patterned nanocomposite microfilaments are fabricated via nanocomposite in&#64257;ltration of 3D interconnected microfluidic networks. The manufacturing of the reinforced beams begins with the fabrication of microfluidic networks, which involves layer-by-layer deposition of fugitive ink filaments using a dispensing robot, filling the empty space between filaments using a low viscosity resin, curing the resin and finally removing the ink.&#160;Self-supported 3D structures with other geometries and many layers (e.g.&#160;a few hundreds layers) could be built using this method. The resulting tubular micro&#64258;uidic networks are then infiltrated with thermosetting nanocomposite suspensions containing nanofillers (e.g.&#160;single-walled carbon nanotubes), and subsequently cured. The infiltration is done by applying a pressure gradient between two ends of the empty network (either by applying a vacuum or vacuum-assisted microinjection). Prior to the infiltration, the nanocomposite suspensions are prepared by dispersing nanofillers into polymer matrices using ultrasonication and three-roll mixing methods. The nanocomposites (i.e.&#160;materials infiltrated) are then solidified under UV exposure/heat cure, resulting in a 3D-reinforced composite structure. The technique presented here enables the design of functional nanocomposite macroscopic products for microengineering applications such as actuators and sensors.

Three-dimensional (3D) microstructured composite beams are fabricated through the directed and localized infiltration of nanocomposites into 3D porous microfluidic networks. The flexibility of this manufacturing method enables the utilization of different thermosetting materials and nanofillers in order to achieve a variety of functional 3D reinforced nanocomposite macroscopic products.

通过微流体渗透制备三维微结构纳米复合材料的制造

Microstructured composite beams reinforced with complex three-dimensionally (3D) patterned nanocomposite microfilaments are fabricated via nanocomposite ...

科研

化学

Fabrication of the Thermoplastic Microfluidic Channels

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using polymer/nanoparticle composite microscale lysis and solid phase extraction columns. The recovered samples are concentrated, small volume samples that are PCRable, without any additional cleanup. Here, we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then, we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns. We demonstrate grafting and polymerization of a carbon nanotube/polymer composite column for bacterial cell lysis. We then show the lysis process followed by solid phase extraction of nucleic acids from the sample on chip using a silica/polymer composite column. The attached protocols contain detailed instructions on how to make both lysis and solid phase extraction columns.

Here we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns.

制备热塑性微流体通道

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using ...

生物学

Printing Thermoresponsive Reverse Molds for the Creation of Patterned Two-component Hydrogels for 3D Cell Culture

Bioprinting is an emerging technology that has its origins in the rapid prototyping industry. The different printing processes can be divided into contact bioprinting1-4 (extrusion, dip pen and soft lithography), contactless bioprinting5-7 (laser forward transfer, ink-jet deposition) and laser based techniques such as two photon photopolymerization8. It can be used for many applications such as tissue engineering9-13, biosensor microfabrication14-16 and as a tool to answer basic biological questions such as influences of co-culturing of different cell types17. Unlike common photolithographic or soft-lithographic methods, extrusion bioprinting has the advantage that it does not require a separate mask or stamp. Using CAD software, the design of the structure can quickly be changed and adjusted according to the requirements of the operator. This makes bioprinting more flexible than lithography-based approaches.
Here we demonstrate the printing of a sacrificial mold to create a multi-material 3D structure using an array of pillars within a hydrogel as an example. These pillars could represent hollow structures for a vascular network or the tubes within a nerve guide conduit. The material chosen for the sacrificial mold was poloxamer 407, a thermoresponsive polymer with excellent printing properties which is liquid at 4 &deg;C and a solid above its gelation temperature ~20 &deg;C for 24.5% w/v solutions18. This property allows the poloxamer-based sacrificial mold to be eluted on demand and has advantages over the slow dissolution of a solid material especially for narrow geometries. Poloxamer was printed on microscope glass slides to create the sacrificial mold. Agarose was pipetted into the mold and cooled until gelation. After elution of the poloxamer in ice cold water, the voids in the agarose mold were filled with alginate methacrylate spiked with FITC labeled fibrinogen. The filled voids were then cross-linked with UV and the construct was imaged with an epi-fluorescence microscope.

A bioprinter was used to create patterned hydrogels based on a sacrificial mold. The poloxamer mold was backfilled with a second hydrogel and then eluted, leaving voids which were filled with a third hydrogel. This method uses fast elution and good printability of poloxamer to generate complex architectures from biopolymers.

打印温敏反向模具图案创作的双组分水凝胶的三维细胞培养

Bioprinting is an emerging technology that has its origins in the rapid prototyping industry. The different printing processes can be divided into contact ...

免疫与感染

Rapid and Low-cost Prototyping of Medical Devices Using 3D Printed Molds for Liquid Injection Molding

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications.

We have devised a method for low-cost and rapid prototyping of liquid elastomer rubber injection molded devices by using fused deposition modeling 3D printers for mold design and a modified desiccator as a liquid injection system.

医疗器械的使用3D印刷模具的液体注射成型快速，低成本原型

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using ...

生物工程

A Soft Tooling Process Chain for Injection Molding of a 3D Component with Micro Pillars

The purpose of this paper is to present the method of a soft tooling process chain employing Additive Manufacturing (AM) for fabrication of injection molding inserts with micro surface features. The Soft Tooling inserts are manufactured by Digital Light Processing (vat photo polymerization) using a photopolymer that can withstand relatively high temperaturea. The part manufactured here has four tines with an angle of 60&#176;. Micro pillars (&#216;200 &#181;m, aspect ratio of 1) are arranged on the surfaces by two rows. Polyethylene (PE) injection molding with the soft tooling inserts is used to fabricate the final parts. This method demonstrates that it is feasible to obtain injection-molded parts with microstructures on complex geometry by additive manufactured inserts. The machining time and cost is reduced significantly compared to conventional tooling processes based on computer numerical control (CNC) machining. The dimensions of the micro features are influenced by the applied additive manufacturing process. The lifetime of the inserts determines that this process is more suitable for pilot production. The precision of the inserts production is limited by the additive manufacturing process as well.

A protocol for fabricating injection molding inserts for complex geometry with micro features on surfaces employing Additive Manufacturing (AM) is presented.

微柱3D 构件注塑成型的软加工工艺链

The purpose of this paper is to present the method of a soft tooling process chain employing Additive Manufacturing (AM) for fabrication of injection ...

工程学

Viability of Bioprinted Cellular Constructs Using a Three Dispenser Cartesian Printer

Tissue engineering has centralized its focus on the construction of replacements for non-functional or damaged tissue. The utilization of three-dimensional bioprinting in tissue engineering has generated new methods for the printing of cells and matrix to fabricate biomimetic tissue constructs. The solid freeform fabrication (SFF) method developed for three-dimensional bioprinting uses an additive manufacturing approach by depositing droplets of cells and hydrogels in a layer-by-layer fashion. Bioprinting fabrication is dependent on the specific placement of biological materials into three-dimensional architectures, and the printed constructs should closely mimic the complex organization of cells and extracellular matrices in native tissue. This paper highlights the use of the Palmetto Printer, a Cartesian bioprinter, as well as the process of producing spatially organized, viable constructs while simultaneously allowing control of environmental factors. This methodology utilizes computer-aided design and computer-aided manufacturing to produce these specific and complex geometries. Finally, this approach allows for the reproducible production of fabricated constructs optimized by controllable printing parameters.

A Cartesian bioprinter was designed and fabricated to allow multi-material deposition in precise, reproducible geometries, while also allowing control of environmental factors. Utilizing the three-dimensional bioprinter, complex and viable constructs may be printed and easily reproduced.

Bioprinted蜂窝构造的可行性使用三分配器笛卡尔打印机

Tissue engineering has centralized its focus on the construction of replacements for non-functional or damaged tissue. The utilization of ...

Frugal Imaging Technique of Capillary Flow Through Three-Dimensional Polymeric Printing Powders

The development of novel imaging techniques of molecular and colloidal transport, including nanoparticles, is an area of active investigation in microfluidic and millifluidic studies. With the advent of three-dimensional (3D) printing, a new domain of materials has emerged, thereby increasing the demand for novel polymers. Specifically, polymeric powders, with average particle sizes on the order of a micron, are experiencing a growing interest from academic and industrial communities. Controlling material tunability at the mesoscopic to microscopic length scales creates opportunities to develop innovative materials, such as gradient materials. Recently, a need for micron-sized polymeric powders has been growing, as clear applications for the material are developing. Three-dimensional printing provides a high-throughput process with a direct link to new applications, driving investigations into the physio-chemical and transport interactions on a mesoscale. The protocol that is discussed in this article provides a non-invasive technique to image fluid flow in packed powder beds, providing high temporal and spatial resolution while leveraging mobile technology that is readily available from mobile devices, such as smartphones. By utilizing a common mobile device, the imaging costs that would normally be associated with an optical microscope are eliminated, resulting in a frugal-science approach. The proposed protocol has successfully characterized a variety of combinations of fluids and powders, creating a diagnostic platform for quickly imaging and identifying an optimal combination of fluid and powder.

The proposed technique will provide a novel, efficient, frugal, and non-invasive approach for imaging fluidic flow through a packed powder bed, yielding high spatial and temporal resolution.

毛细管流通过三维聚合物印刷粉末的节俭成像技术

The development of novel imaging techniques of molecular and colloidal transport, including nanoparticles, is an area of active investigation in ...

Design of an Open-Source, Low-Cost Bioink and Food Melt Extrusion 3D Printer

Three-dimensional (3D) printing is an increasingly popular manufacturing technique that allows highly complex objects to be fabricated with no retooling costs. This increasing popularity is partly driven by falling barriers to entry such as system set-up costs and ease of operation. The following protocol presents the design and construction of an Additive Manufacturing Melt Extrusion (ADDME) 3D printer for the fabrication of custom parts and components. ADDME has been designed with a combination of 3D-printed, laser-cut, and online-sourced components. The protocol is arranged into easy-to-follow sections, with detailed diagrams and parts lists under the headings of framing, y-axis and bed, x-axis, extrusion, electronics, and software. The performance of ADDME is evaluated through extrusion testing and 3D printing of complex objects using viscous cream, chocolate, and Pluronic F-127 (a model for bioinks). The results indicate that ADDME is a capable platform for the fabrication of materials and constructs for use in a wide range of industries. The combination of detailed diagrams and video content facilitates access to low-cost, easy-to-operate equipment for individuals interested in 3D printing of complex objects from a wide range of materials.

The aim of this work is to design and construct a reservoir-based melt extrusion three-dimensional printer made from open-source and low-cost components for applications in the biomedical and food printing industries.

设计开源、低成本生物墨水和食品熔炼挤出3D打印机

Three-dimensional (3D) printing is an increasingly popular manufacturing technique that allows highly complex objects to be fabricated with no retooling ...

在水凝胶基质中生物打印细菌，用于研究运动和生长

3D Printing Bacteria to Study Motility and Growth in Complex 3D Porous Media

Bacteria are ubiquitous in complex three-dimensional (3D) porous environments, such as biological tissues and gels, and subsurface soils and sediments. However, the majority of previous work has focused on studies of cells in bulk liquids or at flat surfaces, which do not fully recapitulate the complexity of many natural bacterial habitats. Here, this gap in knowledge is addressed by describing the development of a method to 3D-print dense colonies of bacteria into jammed granular hydrogel matrices. These matrices have tunable pore sizes and mechanical properties; they physically confine the cells, thus supporting them in 3D. They are optically transparent, allowing for direct visualization of bacterial spreading through their surroundings using imaging. As a proof of this principle, here, the capability of this protocol is demonstrated by 3D printing and imaging non-motile and motile Vibro cholerae, as well as non-motile Escherichia coli, in jammed granular hydrogel matrices with varying interstitial pore sizes.

作者聚焦:研究 3D 水凝胶基质中的细菌生长

This protocol describes a procedure for three-dimensional (3D) printing of bacterial colonies to study their motility and growth in complex 3D porous hydrogel matrices that are more akin to their natural habitats than conventional liquid cultures or Petri dishes.

3D打印细菌研究复杂3D多孔介质中的运动和生长

Bacteria are ubiquitous in complex three-dimensional (3D) porous environments, such as biological tissues and gels, and subsurface soils and sediments. ...

三维热塑性材料的印刷, 以创建自动注射器泵的反馈控制微流控应用

摘要

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此视频中的章节

通过微流体渗透制备三维微结构纳米复合材料的制造

制备热塑性微流体通道

打印温敏反向模具图案创作的双组分水凝胶的三维细胞培养

医疗器械的使用3D印刷模具的液体注射成型快速，低成本原型

微柱3D 构件注塑成型的软加工工艺链

Bioprinted蜂窝构造的可行性使用三分配器笛卡尔打印机

毛细管流通过三维聚合物印刷粉末的节俭成像技术

设计开源、低成本生物墨水和食品熔炼挤出3D打印机

3D打印细菌研究复杂3D多孔介质中的运动和生长

3D打印细菌研究复杂3D多孔介质中的运动和生长