School of Biomedical Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia.
Institute for Biomedical Materials & Devices (IBMD), Faculty of Science, University of Technology Sydney, Sydney, NSW, 2007, Australia.
Sci Rep. 2020 Apr 3;10(1):5929. doi: 10.1038/s41598-020-62569-9.
Inertial microfluidics has been broadly investigated, resulting in the development of various applications, mainly for particle or cell separation. Lateral migrations of these particles within a microchannel strictly depend on the channel design and its cross-section. Nonetheless, the fabrication of these microchannels is a continuous challenging issue for the microfluidic community, where the most studied channel cross-sections are limited to only rectangular and more recently trapezoidal microchannels. As a result, a huge amount of potential remains intact for other geometries with cross-sections difficult to fabricate with standard microfabrication techniques. In this study, by leveraging on benefits of additive manufacturing, we have proposed a new method for the fabrication of inertial microfluidic devices. In our proposed workflow, parts are first printed via a high-resolution DLP/SLA 3D printer and then bonded to a transparent PMMA sheet using a double-coated pressure-sensitive adhesive tape. Using this method, we have fabricated and tested a plethora of existing inertial microfluidic devices, whether in a single or multiplexed manner, such as straight, spiral, serpentine, curvilinear, and contraction-expansion arrays. Our characterizations using both particles and cells revealed that the produced chips could withstand a pressure up to 150 psi with minimum interference of the tape to the total functionality of the device and viability of cells. As a showcase of the versatility of our method, we have proposed a new spiral microchannel with right-angled triangular cross-section which is technically impossible to fabricate using the standard lithography. We are of the opinion that the method proposed in this study will open the door for more complex geometries with the bespoke passive internal flow. Furthermore, the proposed fabrication workflow can be adopted at the production level, enabling large-scale manufacturing of inertial microfluidic devices.
惯性微流控技术得到了广泛的研究，由此产生了各种应用，主要用于颗粒或细胞分离。这些颗粒在微通道内的横向迁移严格依赖于通道的设计及其横截面。然而，这些微通道的制造对于微流控领域来说仍然是一个持续的挑战，其中最受研究的通道横截面仅限于矩形，最近也仅限于梯形微通道。因此，其他横截面难以用标准微制造技术制造的几何形状仍有大量潜力未被开发。在本研究中，通过利用增材制造的优势，我们提出了一种制造惯性微流控器件的新方法。在我们提出的工作流程中，首先通过高分辨率的 DLP/SLA 3D 打印机打印零件，然后使用双面压敏胶带将其粘贴到透明 PMMA 片上。使用这种方法，我们已经制造和测试了大量现有的惯性微流控器件，无论是以单通道还是多通道的方式，例如直通道、螺旋通道、蛇形通道、曲线通道和收缩-扩张阵列。我们使用颗粒和细胞进行的特性分析表明，所生产的芯片可以承受高达 150psi 的压力，且胶带对器件总功能和细胞活力的干扰最小。作为我们方法的多功能性展示，我们提出了一种具有直角三角形横截面的新型螺旋微通道，这在技术上是不可能使用标准光刻来制造的。我们认为，本研究提出的方法将为具有定制被动内部流动的更复杂几何形状打开大门。此外，所提出的制造工作流程可以在生产水平上采用，从而实现惯性微流控器件的大规模制造。
