posted on 2023-11-28, 20:05authored byShaofei Shen, Yali Zhang, Kai Yang, Henryk Chan, Weiwen Li, Xiaoping Li, Chang Tian, Yanbing Niu
Although microfluidic devices have made remarkable strides
in blood
cell separation, there is still a need for further development and
improvement in this area. Herein, we present a novel ultralow aspect
ratio (H/W = 1:36) spiral channel
microfluidic device with ordered micro-obstacles for sheathless and
flow-rate-insensitive blood cell separation. By introducing ordered
micro-obstacles into the spiral microchannels, reduced magnitude fluctuations
in secondary flow across different loops can be obtained through geometric
confinement. As a result, the unique Dean-like secondary flow can
effectively enhance the separation efficiency of particles in different
sizes ranging from 3 to 15 μm. Compared to most existing microfluidic
devices, our system offers several advantages of easy manufacturing,
convenient operation, long-term stability, highly efficient performance
(up to 99.70% rejection efficiency, including platelets), and most
importantly, insensitivity to cell sizes as well as flow rates (allowing
for efficient separation of different-sized blood cells in a wide
flow rate from 1.00 to 2.50 mL/min). The unique characteristics, such
as ultralow aspect ratio, sequential micro-obstacles, and controlled
secondary flow, make our device a promising solution for practical
plasma extraction in biomedical research and clinical applications.