Microfluidics and Nanofluidics

, Volume 9, Issue 4–5, pp 645–655 | Cite as

Characterization of mixing performance for bio-mimetic silicone cilia

  • Kieseok Oh
  • Brandon Smith
  • Santosh Devasia
  • James J. Riley
  • Jae-Hyun ChungEmail author
Research Paper


This article presents the mixing performance of bio-mimetic cilia in a circular microchamber that is compatible with microwell plates. The mixing performance is characterized and compared with those of both diffusion- and vibration-induced mixers. To represent the mixing performance, the 90% mixing time, which was the time span for 90% mixing completion, was measured by analyzing the mixing process of black ink with water. The cilia mixer reduced the 90% mixing time by 8.0- and 1.4 times compared with those of the diffusion- and vibration mixers, respectively. In addition, the coefficient of variation of the 90% mixing time for the cilia mixer was reduced by 3.1- and 2.8 times compared with those of the diffusion- and vibration mixers, respectively. The experimental mixing performance was validated by numerical analysis. The simulations showed that the cilia mixer could significantly reduce the coefficient of variation because the convective flows generated by the cilia rapidly increased the surface area of the ink and thus rapidly decreased the variations in the initial mixing conditions.


Bio-mimetic cilia Microfluidics Micromixer Resonance 



This research was supported by the National Science Foundation (award number: CMMI 0624597) and the Royalty Research Fund at University of Washington.

Supplementary material

Supplementary material 1 (MPG 3263 kb)

Supplementary material 2 (MPG 3263 kb)

Supplementary material 3 (MPG 3263 kb)


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Kieseok Oh
    • 1
  • Brandon Smith
    • 1
  • Santosh Devasia
    • 1
  • James J. Riley
    • 1
  • Jae-Hyun Chung
    • 1
    Email author
  1. 1.Department of Mechanical EngineeringUniversity of WashingtonSeattleUSA

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