Liu Bendong, Tian Baohua, Yang Xu, Li Mohan, Yang Jiahui, Li Desheng, Oh Kwang W
College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, China.
Department of Electrical Engineering, State University of New York at Buffalo, Buffalo, New York 14260, USA.
Biomicrofluidics. 2018 Jun 8;12(3):034111. doi: 10.1063/1.5028419. eCollection 2018 May.
This paper presents a novel manipulation method for micro-objects using acoustically oscillating bubbles with a controllable position based on the gas permeability of polydimethylsiloxane. The oscillating bubble trapped within the side channel attracts the neighboring micro-objects, and the position of the air-liquid interface is controlled by generating temporary pressure difference between the side channel and the air channel. To demonstrate the feasibility of the method in technological applications, polystyrene microparticles of 10 m in diameter were successfully captured, transported, and released. The influence of pressure difference on the movement speed of the air-liquid interface was demonstrated in our experiments, and the manipulation performance was also characterized by varying the frequency of the acoustic excitation and the pressure difference. Since the bubble generation and the air-liquid interface movement in our manipulation method do not need any electrochemical reaction and any high temperature, this on-chip manipulation method provides a controllable, efficient, and noninvasive tool for handling micro-objects such as particles, cells, and other entities. The whole manipulation process, including capturing, transporting, and releasing of particles, spent less than 1 min. It can be used to select the cells and particles in the microfluidic device or change the cell culture medium.
本文基于聚二甲基硅氧烷的气体渗透性，提出了一种利用位置可控的声学振荡气泡对微物体进行新颖的操纵方法。捕获在侧通道内的振荡气泡会吸引相邻的微物体，并且通过在侧通道和空气通道之间产生临时压力差来控制气液界面的位置。为了证明该方法在技术应用中的可行性，成功捕获、运输并释放了直径为10μm的聚苯乙烯微粒。我们的实验证明了压力差对气液界面移动速度的影响，并且还通过改变声激发频率和压力差来表征操纵性能。由于我们的操纵方法中气泡的产生和气液界面的移动不需要任何电化学反应和任何高温，这种片上操纵方法为处理诸如颗粒、细胞和其他实体等微物体提供了一种可控、高效且无创的工具。整个操纵过程，包括颗粒的捕获、运输和释放，耗时不到1分钟。它可用于在微流控装置中选择细胞和颗粒或更换细胞培养基。
