Continuous On-Chip Cell Washing Using Viscoelastic Microfluidics

Hyunjung Lim, Minji Kim, Yeongmu Kim, Seunghee Choo, Tae Eun Kim, Jaesung Han, Byoung Joe Han, Chae Seung Lim, Jeonghun Nam

Research output: Contribution to journalArticlepeer-review


Medium exchange of particles/cells to a clean buffer with a low background is essential for biological, chemical, and clinical research, which has been conventionally conducted using centrifugation. However, owing to critical limitations, such as possible cell loss and physical stimulation of cells, microfluidic techniques have been adopted for medium exchange. This study demonstrates a continuous on-chip washing process in a co-flow system using viscoelastic and Newtonian fluids. The co-flow system was constructed by adding a small amount of biocompatible polymer (xanthan gum, XG) to a sample containing particles or cells and introducing Newtonian fluids as sheath flows. Polymer concentration-dependent and particle size-dependent lateral migration of particles in the co-flow system were examined, and then the optimal concentration and the critical particle size for medium exchange were determined at the fixed total flow rate of 100 μL/min. For clinical applications, the continuous on-chip washing of white blood cells (WBCs) in lysed blood samples was demonstrated, and the washing performance was evaluated using a scanning spectrophotometer.

Original languageEnglish
Article number1658
Issue number9
Publication statusPublished - 2023 Sept

Bibliographical note

Publisher Copyright:
© 2023 by the authors.


  • co-flow
  • viscoelastic fluid
  • washing
  • white blood cell

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Mechanical Engineering
  • Electrical and Electronic Engineering


Dive into the research topics of 'Continuous On-Chip Cell Washing Using Viscoelastic Microfluidics'. Together they form a unique fingerprint.

Cite this