A microfluidic electrostatic separator based on pre-charged droplets

作者：Rao, Lang; Cai, Bo; Wang, Jieli; Meng, Qianfang; Ma, Chi; He, Zhaobo; Xu, Junhua; Huang, Qinqin; Li, Shasha; Cen, Yi; Guo, Shishang; Liu, Wei^*; Zhao, Xing-zhong

来源：Sensors and Actuators B: Chemical , 2015, 210: 328-335.

DOI：10.1016/j.snb.2014.12.057

• Microfluidic
• Electric
• Droplet charging
• Cell sorting
• 3D electrodes

In this work, a single-layer electric separator based on droplet microfluidics is demonstrated for cell sorting. We introduce a droplet pre-charging stratagem to reduce the voltages needed and increase droplet maneuverability. This stratagem and subsequent sorting process is implemented due to the effect of analogous uniform electric fields, which are generated by the 3D electrodes fabricated through injecting conductive silver paste into chambers in the PDMS layer. The mechanism of this droplet pre-charging process is experimentally verified and the amount of the inductive charges is quantitatively calculated. We also analyze the influence of the interaction between droplet size and channel walls on the manipulations of charge-carried droplets under certain electric fields. After parameter optimization, droplets with single cell encapsulated inside are separated out from other ones using this separator, and cell viability assay indicates that good cell status is maintained through the whole electric cascade.

• 出版日期2015-4
• 单位武汉大学