Gao Zehang, Peng Huo, Zhu Minjie, Wu Lei, Jia Chunping, Zhou Hongbo, Zhao Jianlong
State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China.
Micromachines (Basel). 2019 Apr 29;10(5):291. doi: 10.3390/mi10050291.
In droplet-based microfluidics, visualizing and modulating of droplets is often prerequisite. In this paper, we report a facile strategy for visualizing and modulating high-throughput droplets in microfluidics. In the strategy, by modulating the sampling frequency of a flash light with the droplet frequency, we are able to map a real high frequency signal to a low frequency signal, which facilitates visualizing and feedback controlling. Meanwhile, because of not needing synchronization signals, the strategy can be directly implemented on any droplet-based microfluidic chips. The only cost of the strategy is an additional signal generator. Moreover, the strategy can catch droplets with frequency up to several kilohertz, which covers the range of most high-throughput droplet-based microfluidics. In this paper, the principle, setup and procedure were introduced. Finally, as a demonstration, the strategy was also implemented in a miniaturized picoinjector in order to monitor and control the injection dosage to droplets. We expect that this facile strategy supplies a low-cost yet effective imaging system that can be easily implemented in miniaturized microfluidic systems or general laboratories.
在基于液滴的微流控技术中，对液滴进行可视化和调控通常是先决条件。在本文中，我们报告了一种在微流控中对高通量液滴进行可视化和调控的简便策略。在该策略中，通过使闪光灯的采样频率与液滴频率同步，我们能够将一个实际的高频信号映射为一个低频信号，这便于进行可视化和反馈控制。同时，由于不需要同步信号，该策略可直接在任何基于液滴的微流控芯片上实现。该策略唯一的成本是一个额外的信号发生器。此外，该策略能够捕获频率高达数千赫兹的液滴，这涵盖了大多数基于高通量液滴的微流控技术的范围。本文介绍了其原理、装置和步骤。最后，作为演示，该策略还在一个小型化的皮升注射器中得以实施，以便监测和控制向液滴的注射剂量。我们期望这种简便的策略能提供一种低成本但有效的成像系统，该系统能够轻松地在小型化微流控系统或普通实验室中实现。
