Park Suhee, Ryu Jaewook, Han Ki-Ho
Department of Nanoscience and Engineering, Center for Nano Manufacturing, Inje University, Gimhae, 50834, Republic of Korea.
Lab Chip. 2025 Jan 14;25(2):225-234. doi: 10.1039/d4lc00744a.
Droplets are essential in a wide range of microfluidic applications, but traditional passive droplet generation methods suffer from slow response speed and the need for precise flow rate adjustment. Here, we present an active droplet generation method through electrowetting-on-dielectric (EWOD). Electrowetting is a technique that uses an electric field to change the wettability of a surface. In our method, we apply an electric field to the laminar flow of the dispersed and continuous phases in a microchannel, which induces the discretization of the dispersed thread and leads to droplet formation. A key feature of the proposed active droplet-generating microfluidic device is the reusability of the EWOD actuation substrate, dramatically reducing operational costs. In addition, this approach offers significant advantages over passive methods, including fast response speeds, a wider range of droplet sizes, and greater control over droplet size. In addition, the ultrathin polymer film used in this device allows for a low electrowetting voltage, which helps to prevent damage to encapsulated cells. We believe that our active droplet generation method is a promising new method for generating droplets in microfluidic applications. It is faster, more versatile, and more precise than passive methods, making it ideal for a wide range of applications, including single-cell genomics and drug discovery.
液滴在广泛的微流控应用中至关重要，但传统的被动式液滴生成方法存在响应速度慢和需要精确调节流速的问题。在此，我们提出一种通过介电电泳（EWOD）的主动式液滴生成方法。介电电泳是一种利用电场改变表面润湿性的技术。在我们的方法中，我们对微通道中分散相和连续相的层流施加电场，这会导致分散的液柱离散化并形成液滴。所提出的主动式液滴生成微流控装置的一个关键特性是EWOD驱动基板的可重复使用性，这大大降低了运营成本。此外，这种方法相对于被动方法具有显著优势，包括响应速度快、液滴尺寸范围更广以及对液滴尺寸的控制更强。此外，该装置中使用的超薄聚合物膜允许使用低介电电泳电压，这有助于防止对封装细胞造成损伤。我们相信，我们的主动式液滴生成方法是微流控应用中一种很有前景的新的液滴生成方法。它比被动方法更快、更通用且更精确，使其非常适合包括单细胞基因组学和药物发现在内的广泛应用。
