Zhang Haipeng, Ryu Sangjin
Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA.
Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA.
HardwareX. 2020 Jun 27;8:e00121. doi: 10.1016/j.ohx.2020.e00121. eCollection 2020 Oct.
Hydrogel beads are widely used in various applications, but producing such beads often requires complicated devices. Instead, we propose an easy-to-adopt, cost effective, open source hydrogel bead generator. This generator consists of two modules. The first module rotates two immiscible liquids in rigid body motion: mineral oil as the continuous phase (CP) liquid on top, and a hydrogel cross-linking (CL) liquid at bottom. The second module injects a hydrogel pre-polymer solution as the dispersed phase (DP) liquid into the rotating CP liquid. As the DP liquid flows out of a syringe needle, its drops are pinched off by the shear force from the CP liquid, and move with the CP liquid while settling down. When the drops enter the CL liquid, they become hydrogel beads. Experiments using water and mineral oil showed that the size of produced drops could be controlled by adjusting the flow speed of the CP and DP liquids. A demonstration using alginate showed that the proposed generator could successfully create alginate gel beads of uniform size and shape.
水凝胶珠广泛应用于各种领域，但生产此类珠子通常需要复杂的设备。相反，我们提出了一种易于采用、成本效益高的开源水凝胶珠生成器。该生成器由两个模块组成。第一个模块使两种互不相溶的液体做刚体运动旋转：顶部的矿物油作为连续相（CP）液体，底部的水凝胶交联（CL）液体。第二个模块将水凝胶预聚物溶液作为分散相（DP）液体注入旋转的CP液体中。当DP液体从注射器针头流出时，其液滴被CP液体的剪切力夹断，并在沉降的同时随CP液体移动。当液滴进入CL液体时，它们就变成了水凝胶珠。用水和矿物油进行的实验表明，通过调节CP和DP液体的流速可以控制所产生液滴的大小。使用藻酸盐进行的演示表明，所提出的生成器能够成功地制造出尺寸和形状均匀的藻酸盐凝胶珠。
