Milliseconds microfluidic chaotic bubble mixer

  • Xiaole Mao
  • Bala Krishna Juluri
  • Michael Ian Lapsley
  • Zackary Stoeri Stratton
  • Tony Jun HuangEmail author
Short Communication


In this study, we report a rapid microfluidic mixing device based on chaotic advection induced by microbubble–fluid interactions. The device includes inlets for to-be-mixed fluids and nitrogen gas. A side-by-side laminar flow segmented by monodisperse microbubbles is generated when the fluids and the nitrogen are co-injected through a flow focusing micro-orifice. The flow subsequently enters a series of hexagonal expansion chambers, in which the hydrodynamic interaction among the microbubbles results in the stretch and fold of segmented fluid volumes and rapid mixing and homogenization. We characterize the performance of the microfluidic mixer and demonstrate rapid mixing within 20 ms. We further show that bubbles can be conveniently removed from the mixed fluids using a microfluidic comb structure on completion of the mixing.


Chaotic advection Microbubble Microfluidics Rapid mixing 



Authors thank Daniel Ahmed and Aitan Lawit for help in the manuscript preparation. This research was supported by National Science Foundation (ECCS-0824183 and ECCS-0801922) and the Penn State Center for Nanoscale Science (MRSEC). Components of this study were conducted at the Penn State node of the NSF-funded National Nanotechnology Infrastructure Network (NNIN).


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Xiaole Mao
    • 1
    • 2
  • Bala Krishna Juluri
    • 1
  • Michael Ian Lapsley
    • 1
  • Zackary Stoeri Stratton
    • 1
  • Tony Jun Huang
    • 1
    • 2
    Email author
  1. 1.Department of Engineering Science and MechanicsPennsylvania State UniversityUniversity ParkUSA
  2. 2.Department of BioengineeringPennsylvania State UniversityUniversity ParkUSA

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