Wang Zongjie, Samanipour Roya, Gamaleldin Mohamed, Sakthivel Kabilan, Kim Keekyoung
School of Engineering, University of British Columbia , Kelowna, British Columbia V1V 1V7, Canada.
Biomicrofluidics. 2016 Sep 27;10(5):054110. doi: 10.1063/1.4963666. eCollection 2016 Sep.
Microdroplets have been widely used in various biomedical applications. During droplet generation, parameters are manually adjusted to achieve the desired size of droplets. This process is tedious and time-consuming. In this paper, we present a fully automated system for controlling the size of droplets to optimize droplet generation parameters in a microfluidic flow-focusing device. The developed system employed a novel image processing program to measure the diameter of droplets from recorded video clips and correspondingly adjust the flow rates of syringe pumps to obtain the required diameter of droplets. The system was tested to generate phosphate-buffered saline and 8% polyethylene (glycol) diacrylate prepolymer droplets and regulate its diameters at various flow rates. Experimental results demonstrated that the difference between droplet diameters from the image processing and manual measurement is not statistically significant and the results are consistent over five repetitions. Taking the advantages of the accurate image processing method, the size of the droplets can be optimized in a precise and robust manner via automatically adjusting flow rates by the feedback control. The system was used to acquire quantitative data to examine the effects of viscosity and flow rates. Droplet-based experiments can be greatly facilitated by the automatic droplet generation and optimization system. Moreover, the system is able to provide quantitative data for the modelling and application of droplets with various conditions in a high-throughput way.
微滴已广泛应用于各种生物医学应用中。在微滴生成过程中,参数需手动调整以达到所需的微滴尺寸。此过程繁琐且耗时。在本文中,我们提出了一种全自动系统,用于控制微滴尺寸,以优化微流控流动聚焦装置中的微滴生成参数。所开发的系统采用了一种新颖的图像处理程序,从录制的视频片段中测量微滴直径,并相应地调整注射泵的流速,以获得所需的微滴直径。该系统经过测试,用于生成磷酸盐缓冲盐水和8%聚乙二醇二丙烯酸酯预聚物微滴,并在不同流速下调节其直径。实验结果表明,图像处理得到的微滴直径与手动测量结果之间的差异无统计学意义,且在五次重复实验中结果一致。利用精确图像处理方法的优势,通过反馈控制自动调节流速,可以精确且稳健地优化微滴尺寸。该系统用于获取定量数据,以研究粘度和流速的影响。自动微滴生成和优化系统可极大地促进基于微滴的实验。此外,该系统能够以高通量方式为各种条件下微滴的建模和应用提供定量数据。