Abbasi Reha, LeFevre Thomas B, Benjamin Aaron D, Thornton Isaak J, Wilking James N
Center for Biofilm Engineering, Montana State University, 214 Roberts Hall, Bozeman, MT 59717, USA.
Lab Chip. 2021 May 18;21(10):2050-2058. doi: 10.1039/d1lc00135c.
Hydrogels are soft, water-based polymer gels that are increasingly used to fabricate free-standing fluidic devices for tissue and biological engineering applications. For many of these applications, pressurized liquid must be driven through the hydrogel device. To couple pressurized liquid to a hydrogel device, a common approach is to insert tubing into a hole in the gel; however, this usually results in leakage and expulsion of the tubing, and other options for coupling pressurized liquid to hydrogels remain limited. Here, we describe a simple coupling approach where microfluidic tubing is inserted into a plastic, 3D-printed bulb-shaped connector, which "pops" into a 3D-printed socket in the gel. By systematically varying the dimensions of the connector relative to those of the socket entrance, we find an optimal head-socket ratio that provides maximum resistance to leakage and expulsion. The resulting connection can withstand liquid pressures on the order of several kilopascals, three orders of magnitude greater than traditional, connector-free approaches. We also show that two-sided connectors can be used to link multiple hydrogels to one another to build complex, reconfigurable hydrogel systems from modular components. We demonstrate the potential usefulness of these connectors by established long-term nutrient flow through a 3D-printed hydrogel device containing bacteria. The simple coupling approach outlined here will enable a variety of applications in hydrogel fluidics.
水凝胶是一种柔软的、基于水的聚合物凝胶，越来越多地用于制造用于组织和生物工程应用的独立式流体装置。对于许多此类应用，必须将加压液体驱动通过水凝胶装置。为了将加压液体与水凝胶装置连接起来，一种常见的方法是将管道插入凝胶中的孔中；然而，这通常会导致管道泄漏和排出，并且将加压液体与水凝胶连接的其他选择仍然有限。在这里，我们描述了一种简单的连接方法，即将微流体管道插入一个塑料的、3D打印的灯泡形连接器中，该连接器“卡入”凝胶中的一个3D打印插座中。通过系统地改变连接器相对于插座入口的尺寸，我们发现了一个最佳的头部-插座比率，该比率提供了最大的抗泄漏和排出能力。由此产生的连接能够承受几千帕斯卡量级的液体压力，比传统的无连接器方法高出三个数量级。我们还表明，双面连接器可用于将多个水凝胶相互连接，以从模块化组件构建复杂的、可重新配置的水凝胶系统。我们通过在一个包含细菌的3D打印水凝胶装置中建立长期营养流，证明了这些连接器的潜在用途。这里概述的简单连接方法将使水凝胶流体学中的各种应用成为可能。
