Microfluidics and Nanofluidics

, Volume 18, Issue 2, pp 175–184 | Cite as

Generation of tunable and pulsatile concentration gradients via microfluidic network

  • Bingpu Zhou
  • Wei Xu
  • Cong Wang
  • Yeungyeung Chau
  • Xiping Zeng
  • Xi-Xiang Zhang
  • Rong Shen
  • Weijia WenEmail author
Research Paper


We demonstrate a compact Polydimethylsiloxane microfluidic chip which can quickly generate ten different chemical concentrations simultaneously. The concentration magnitude of each branch can be flexibly regulated based on the flow rate ratios of the two injecting streams. The temporal/pulsatile concentration gradients are achieved by integrating on-chip pneumatic actuated valves controlled by the external signals. The temporal concentration gradients can also be tuned precisely by varying applied frequency and duty cycle of the trigger signal. It is believed that such microdevice will be potentially used for some application areas of producing stable chemical gradients as well as allowing fast, pulsatile gradient transformation in seconds.


PDMS Concentration Gradient Duty Cycle Microfluidic Chip Hydraulic Resistance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We would like to thank Prof. Andrew W. O. Poon’s research group, of Department of Electronic and Computer Engineering in HKUST, for their assistance in COMSOL Multiphysics simulations. This publication is based on work partially supported by Award No. SA-C0040/UK-C0016, made by King Abdullah University of Science and Technology (KAUST), Hong Kong RGC Grants HKUST 604710 and 605411, and National Natural Science Foundation of China (Grant No. 11290165). The work is also partially supported by the Nanoscience and Nanotechnology Program at HKUST.

Supplementary material

10404_2014_1432_MOESM1_ESM.docx (300 kb)
Supplementary material 1 (DOCX 299 kb)

Supplementary material 2 (AVI 3012 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Bingpu Zhou
    • 1
  • Wei Xu
    • 2
  • Cong Wang
    • 1
  • Yeungyeung Chau
    • 1
  • Xiping Zeng
    • 1
  • Xi-Xiang Zhang
    • 2
  • Rong Shen
    • 3
  • Weijia Wen
    • 1
    • 4
    Email author
  1. 1.Nano Science and Technology Program and KAUST-HKUST Micro/Nanofluidic Joint LaboratoryThe Hong Kong University of Science and TechnologyKowloonHong Kong
  2. 2.Imaging and Characterization Core Lab and Division of Physical Science and EngineeringKing Abdullah University of Science and TechnologyThuwalKingdom of Saudi Arabia
  3. 3.Institute of PhysicsChinese Academy of SciencesBeijingChina
  4. 4.Department of PhysicsThe Hong Kong University of Science and TechnologyKowloonHong Kong

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