Murata Yuki, Nakashoji Yuta, Kondo Masaki, Tanaka Yugo, Hashimoto Masahiko
Department of Chemical Engineering and Materials Science, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto, Japan.
Electrophoresis. 2018 Feb;39(3):504-511. doi: 10.1002/elps.201700247. Epub 2017 Sep 1.
We previously developed a technique that enabled automatic creation of monodisperse water-in-oil droplets with the use of an air-evacuated PDMS microfluidic device. Although the device generated droplets over a long-time period, the production rate was slow (∼10 droplets per second). In the current study, we aimed to improve this rate, using the same fluid pumping principle described in our previous work, by remodeling our device configuration. To achieve this aim, we developed a new device with a much larger PDMS surface area-to-volume ratio within the air-trapping void space (178 cm ), than that of our earlier device (5.0 cm ). This design approach was based on the idea that a larger PDMS surface area-to-volume ratio was likely to create a higher vacuum inside the void space, thereby contributing to faster liquid flow and an increased droplet generation rate. The new device consisting of five layers featuring a degassed PDMS slab as a detachable liquid-suction actuator, which was stacked on a lower microfluidic layer. In this device, the rate of droplet production increased during the time-course droplet formation and reached ca. 470 droplets per second immediately before completely consuming the loaded aqueous solution (20 μL).
我们之前开发了一种技术，可利用抽真空的聚二甲基硅氧烷（PDMS）微流控装置自动生成单分散的油包水液滴。尽管该装置能在较长时间内生成液滴，但其生产率较低（约每秒10个液滴）。在当前研究中，我们旨在通过重塑装置结构，采用我们之前工作中描述的相同流体泵送原理来提高这一速率。为实现这一目标，我们开发了一种新装置，其在捕气空隙空间（178平方厘米）内的PDMS表面积与体积之比，比我们早期的装置（5.0平方厘米）大得多。这种设计方法基于这样一种理念，即更大的PDMS表面积与体积之比可能会在空隙空间内产生更高的真空度，从而有助于实现更快的液体流动和更高的液滴生成速率。新装置由五层组成，其特征在于有一个脱气的PDMS平板作为可拆卸的液体抽吸致动器，该平板堆叠在较低的微流控层上。在该装置中，液滴生成速率在液滴形成的时间过程中不断增加，在即将完全消耗加载的水溶液（20微升）之前达到约每秒470个液滴。
