Yang Yue, Bai Weitao, Dong Jun, Lv Huimin, Zhu Yonggang
Center for Microflows and Nanoflows, School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen 518055, China.
Biomicrofluidics. 2022 Sep 6;16(5):054101. doi: 10.1063/5.0098302. eCollection 2022 Sep.
The alveolus is a basic functional unit of the human respiratory system, and the airflow in the alveoli plays an important role in determining the transport and deposition of particulate matter, which is crucial for inhaled disease diagnosis and drug delivery. In the present study, taking advantage of the precise control ability of the microfluidic technique, a rhythmically expanding alveolar chip with multiple alveoli in two generations is designed and both the geometric and kinematic similarities are matched with the real human respiration system. With the help of a micro-PIV measurement system, the microflow patterns inside each alveolus can be studied. The observed vortex and radial flow patterns and the discovery of stagnant saddle points are similar to those captured in our previous platform with only one alveolus [Lv ., Lab Chip , 2394-2402 (2020)]. However, the interactions between multiple alveoli also uncover new phenomena, such as the finding of stagnant saddle points in non-vortex flow patterns and significant differences in the flow pattern around the points between the time of T/4 and 3T/4. The obtained results could enrich the understanding of microflow in a whole alveolar tree with multiple generations.
肺泡是人体呼吸系统的基本功能单位，肺泡内的气流在决定颗粒物的传输和沉积方面起着重要作用，这对吸入性疾病诊断和药物输送至关重要。在本研究中，利用微流控技术的精确控制能力，设计了一种具有两代多个肺泡的节律性扩张肺泡芯片，其几何形状和运动学相似性均与真实人体呼吸系统相匹配。借助微粒子图像测速测量系统，可以研究每个肺泡内的微流模式。观察到的涡旋和径向流模式以及停滞鞍点的发现与我们之前仅具有一个肺泡的平台所捕获的情况相似[Lv.，《芯片实验室》，2394 - 2402(2020)]。然而，多个肺泡之间的相互作用也揭示了新现象，例如在非涡旋流模式中发现停滞鞍点以及在T/4和3T/4时刻之间这些点周围的流模式存在显著差异。所获得的结果可以丰富对具有多代的整个肺泡树中微流的理解。
