Microfluidics and Nanofluidics

, Volume 19, Issue 3, pp 711–720 | Cite as

Mixing in an enclosed microfluidic chamber through moving boundary motions

  • Chengpeng Yang
  • Dinglong Hu
  • Baoce Sun
  • Xin Cui
  • Qian Zhu
  • Raymond H. W. LamEmail author
Research Paper


Mixing in enclosed culture micro-chambers is an important criterion on achieving the long-term cell growth with more consistent characteristics spatially distributed in the microfluidic environments. Here, we report a microfluidic mixer composed of multiple deformable membranes to drive circulation flows within the culture region in a peristaltic manner. This mechanically driven mixing scheme has the advantages over many others existing mixing schemes by inducing negligible shear stress over cells without side effects to the viability and growth characteristics. The membrane movements can induce moving boundary motions of the liquid volume contained in the culture chamber. The flow characteristics such as the velocity profile and shear stress are investigated by lumped-element modeling and computational simulations. Both experiments and simulations are performed to show the effectiveness of the mixing of both soluble substances and sub-microscale particles, including bacteria. The mixing performance under different operation parameters (e.g., membrane size and membrane switching time) is also investigated for the optimized operation. Further, the dental bacteria Streptococcus mutans are cultured for 2 days to demonstrate that the reported mixing scheme can generate a more even distribution of growth, which may be further applied for a uniform dental biofilm development in vitro for the related biofilm research. Additionally, this micro-mixer is highly compatible with the widely used soft lithography technique, and hence, it can be directly integrated with general microfluidic devices for extended biomedical diagnosis and bio-sample processing applications.


PDMS Standard Deviation Switching Time Control Channel PDMS Membrane 
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 sincerely thank for the supports during the early development of this research from Department of Mechanical Engineering in Massachusetts Institute of Technology. We appreciate the invaluable advices from Dr. T. Thorsen. We thank for the financial supports from City University of Hong Kong (Seed Grant; project #7003019), Croucher Foundation Scholarship and General Research Grant of Hong Kong Research Grant Council (project# RGC115813).

Supplementary material

10404_2015_1596_MOESM1_ESM.pdf (603 kb)
Supplementary material 1 (PDF 603 kb)


  1. Abbas Y, Miwa J, Zengerle R, von Stetten F (2013) Active continuous-flow micromixer using an external braille pin actuator array. Micromachines 4:80–89CrossRefGoogle Scholar
  2. Materne E-M et al (2013) Dynamic culture of human liver equivalents inside a micro-bioreactor for long-term substance testing. In: BMC Proceedings of BioMed Central Ltd. Suppl 6:P72Google Scholar
  3. Ansari MA, Kim K-Y, Anwar K, Kim SM (2010) A novel passive micromixer based on unbalanced splits and collisions of fluid streams. J Micromech Microeng 20:055007CrossRefGoogle Scholar
  4. Armani D, Liu C, Aluru N (1999) Re-configurable fluid circuits by PDMS elastomer micromachining. In: Twelfth IEEE International Conference on Micro Electro Mechanical Systems, 1999. MEMS’99, Ieee, pp 222–227Google Scholar
  5. Byus CV, Pieper SE, Adey WR (1987) The effects of low-energy 60-Hz environmental electromagnetic fields upon the growth-related enzyme ornithine decarboxylase. Carcinogenesis 8:1385–1389CrossRefGoogle Scholar
  6. Capretto L, Cheng W, Hill M, Zhang X (2011) Micromixing within microfluidic devices. Microfluidics. Springer, New York, pp 27–68CrossRefGoogle Scholar
  7. Cui X, Yip HM, Zhu Q, Yang C, Lam RHW (2014) Microfluidic long-term differential oxygenation for bacterial growth characteristics analyses. RSC Adv 4:16662–16673. doi: 10.1039/C4RA01577K CrossRefGoogle Scholar
  8. Friend J, Yeo LY (2011) Microscale acoustofluidics: microfluidics driven via acoustics and ultrasonics. Rev Mod Phys 83:647CrossRefGoogle Scholar
  9. Fu L-M, Ju W-J, Tsai C-H, Hou H-H, Yang R-J, Wang Y-N (2013) Chaotic vortex micromixer utilizing gas pressure driving force. Chem Eng J 214:1–7CrossRefGoogle Scholar
  10. Fu L-M, Fang W-C, Hou H-H, Wang Y-N, Hong T-F (2014) Rapid vortex microfluidic mixer utilizing double-heart chamber. Chem Eng J 249:246–251CrossRefGoogle Scholar
  11. Hsiung S-K, Lee C-H, Lin J-L, Lee G-B (2007) Active micro-mixers utilizing moving wall structures activated pneumatically by buried side chambers. J Micromech Microeng 17:129CrossRefGoogle Scholar
  12. Hyon Y, Marcos, Powers TR, Stocker R, Fu HC (2012) The wiggling trajectories of bacteria. J Fluid Mech 705:58–76CrossRefzbMATHGoogle Scholar
  13. Jang L-S, Chao S-H, Holl MR, Meldrum DR (2007) Resonant mode-hopping micromixing. Sens Actuators A Phys 138:179–186CrossRefGoogle Scholar
  14. Kim S-J, Wang F, Burns MA, Kurabayashi K (2009) Temperature-programmed natural convection for micromixing and biochemical reaction in a single microfluidic chamber. Anal Chem 81:4510–4516CrossRefGoogle Scholar
  15. Koh JBY, Marcos (2015) The study of spermatozoa and sorting in relation to human reproduction. Microfluid Nanofluid pp. 1–20Google Scholar
  16. Lam RHW, Kim M-C, Thorsen T (2009) Culturing aerobic and anaerobic bacteria and mammalian cells with a microfluidic differential oxygenator. Anal Chem 81:5918–5924. doi: 10.1021/ac9006864 CrossRefGoogle Scholar
  17. Lange H, Taillandier P, Riba JP (2001) Effect of high shear stress on microbial viability. J Chem Technol Biotechnol 76:501–505CrossRefGoogle Scholar
  18. Lee C-Y, Chang C-L, Wang Y-N, Fu L-M (2011a) Microfluidic mixing: a review. Int J Mol Sci 12:3263–3287CrossRefGoogle Scholar
  19. Lee KS, Boccazzi P, Sinskey AJ, Ram RJ (2011b) Microfluidic chemostat and turbidostat with flow rate, oxygen, and temperature control for dynamic continuous culture. Lab Chip 11:1730–1739CrossRefGoogle Scholar
  20. Legazpi L, Laca A, Díaz M (2009) Kinetic analysis of hybridoma cells viability under mechanical shear stress with and without serum protection. Bioprocess Biosyst Eng 32:717–722CrossRefGoogle Scholar
  21. Lin C-H, Tsai C-H, Pan C-W, Fu L-M (2007) Rapid circular microfluidic mixer utilizing unbalanced driving force. Biomed Microdevices 9:43–50CrossRefGoogle Scholar
  22. Lin Y-H, Wang C-C, Lei KF (2014) Bubble-driven mixer integrated with a microfluidic bead-based ELISA for rapid bladder cancer biomarker detection. Biomed Microdevices 16:199–207CrossRefGoogle Scholar
  23. Liu RH, Yang J, Pindera MZ, Athavale M, Grodzinski P (2002) Bubble-induced acoustic micromixing. Lab Chip 2:151–157CrossRefGoogle Scholar
  24. Loesche WJ (1986) Role of Streptococcus mutans in human dental decay. Microbiol Rev 50:353–380Google Scholar
  25. Mansur EA, Ye M, Wang Y, Dai Y (2008) A state-of-the-art review of mixing in microfluidic mixers. Chin J Chem Eng 16:503–516CrossRefGoogle Scholar
  26. Marcos, Stocker R (2006) Microorganisms in vortices: a microfluidic setup. Limnol Oceanogr Methods 4:392–398CrossRefGoogle Scholar
  27. Marcos, Fu HC, Powers TR, Stocker R (2009) Separation of microscale chiral objects by shear flow. Phys Rev Lett 102:158103CrossRefGoogle Scholar
  28. Marcos, Seymour JR, Luhar M, Durham WM, Mitchell JG, Macke A, Stocker R (2011) Microbial alignment in flow changes ocean light climate. Proc Natl Acad Sci 108:3860–3864CrossRefGoogle Scholar
  29. Marcos, Fu HC, Powers TR, Stocker R (2012) Bacterial rheotaxis. Proc Natl Acad Sci 109:4780–4785CrossRefGoogle Scholar
  30. Marcos, Tran NP, Saini AR, Ong KCH, Chia WJ (2014) Analysis of a swimming sperm in a shear flow. Microfluid Nanofluid 17:809–819CrossRefGoogle Scholar
  31. Nguyen N-T, Wu Z (2005) Micromixers—a review. J Micromech Microeng 15:R1CrossRefGoogle Scholar
  32. Park C, Wereley ST (2013) Rapid generation and manipulation of microfluidic vortex flows induced by AC electrokinetics with optical illumination. Lab Chip 13:1289–1294CrossRefGoogle Scholar
  33. Peng Z-C, Hesketh P, Mao W, Alexeev A, Lam W (2011) A microfluidic mixer based on parallel, high-speed circular motion of individual microbeads in a rotating magnetic field. In: Solid-State Sensors, Actuators and Microsystems Conference (TRANSDUCERS), 16th International, 2011. IEEE, pp 1292–1295Google Scholar
  34. Pitt WG, Ross SA (2003) Ultrasound increases the rate of bacterial cell growth. Biotechnol Prog 19:1038–1044CrossRefGoogle Scholar
  35. Sayar E, Farouk B (2011) Acoustically generated flows in microchannel flexural plate wave sensors: effects of compressibility. Sens Actuators A Phys 171:317–323CrossRefGoogle Scholar
  36. Sayar E, Farouk B (2012) Multifield analysis of a piezoelectric valveless micropump: effects of actuation frequency and electric potential. Smart Mater Struct 21:075002CrossRefGoogle Scholar
  37. Sayar E, Farouk B (2015) Bulk acoustic wave piezoelectric micropumps with stationary flow rectifiers: a three-dimensional structural/fluid dynamic investigation. Microfluid Nanofluid pp. 1–13Google Scholar
  38. Scragg A, Allan E, Leckie F (1988) Effect of shear on the viability of plant cell suspensions. Enzyme Microb Technol 10:361–367CrossRefGoogle Scholar
  39. Senturia SD (2001) Microsystem design, vol 3. Kluwer Academic Publishers, BostonGoogle Scholar
  40. Shiragami N, Unno H (1994) Effect of shear stress on activity of cellular enzyme in animal cell. Bioprocess Eng 10:43–45CrossRefGoogle Scholar
  41. Timoshenko S, Woinowsky-Krieger S, Woinowsky-Krieger S (1959) Theory of plates and shells, vol 2. McGraw-hill, New YorkGoogle Scholar
  42. Tofteberg T, Skolimowski M, Andreassen E, Geschke O (2010) A novel passive micromixer: lamination in a planar channel system. Microfluid Nanofluid 8:209–215CrossRefGoogle Scholar
  43. Unger MA, Chou H-P, Thorsen T, Scherer A, Quake SR (2000) Monolithic microfabricated valves and pumps by multilayer soft lithography. Science 288:113–116CrossRefGoogle Scholar
  44. Vianale G, Reale M, Amerio P, Stefanachi M, Di Luzio S, Muraro R (2008) Extremely low frequency electromagnetic field enhances human keratinocyte cell growth and decreases proinflammatory chemokine production. Br J Dermatol 158:1189–1196CrossRefGoogle Scholar
  45. Voth GA, Saint T, Dobler G, Gollub JP (2003) Mixing rates and symmetry breaking in two-dimensional chaotic flow. Phys Fluids (1994-present) 15:2560–2566MathSciNetCrossRefGoogle Scholar
  46. Watanabe S, Dawes C (1990) Salivary flow rates and salivary film thickness in five-year-old children. J Dent Res 69:1150–1153CrossRefGoogle Scholar
  47. West J et al (2002) Application of magnetohydrodynamic actuation to continuous flow chemistry. Lab Chip 2:224–230CrossRefGoogle Scholar
  48. Wu M-H, Huang S-B, Cui Z, Cui Z, Lee G-B (2008) Development of perfusion-based micro 3-D cell culture platform and its application for high throughput drug testing. Sens Actuators B Chem 129:231–240CrossRefGoogle Scholar
  49. Xia H, Seah Y, Liu Y, Wang W, Toh AG, Wang Z (2014) Anti-solvent precipitation of solid lipid nanoparticles using a microfluidic oscillator mixer. Microfluid Nanofluid pp. 1–8Google Scholar
  50. Yan D, Yang C, Miao J, Lam Y, Huang X (2009) Enhancement of electrokinetically driven microfluidic T-mixer using frequency modulated electric field and channel geometry effects. Electrophoresis 30:3144–3152CrossRefGoogle Scholar
  51. Yeo LY, Friend JR (2009) Ultrafast microfluidics using surface acoustic waves. Biomicrofluidics 3:012002CrossRefGoogle Scholar
  52. Zhu X, Kim ES (1998) Microfluidic motion generation with acoustic waves. Sens Actuators A Phys 66:355–360CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Chengpeng Yang
    • 1
  • Dinglong Hu
    • 1
  • Baoce Sun
    • 1
  • Xin Cui
    • 1
  • Qian Zhu
    • 1
  • Raymond H. W. Lam
    • 1
    Email author
  1. 1.Department of Mechanical and Biomedical EngineeringCity University of Hong KongKowloon TongHong Kong

Personalised recommendations