Micromixing with spark-generated cavitation bubbles

  • Salvatore Surdo
  • Alberto Diaspro
  • Martí DuocastellaEmail author
Research Paper


The intrinsic laminarity of microfluidic devices impedes the mixing of multiple fluids over short temporal or spatial scales. Despite the existence of several mixers capable of stirring and stretching the flows to promote mixing, most approaches sacrifice temporal or spatial control, portability, or flexibility in terms of operating flow rates. Here, we report a novel method for rapid micromixing based on the generation of cavitation bubbles. By using a portable battery-powered electric circuit, we induce a localized electric spark between two tip electrodes perpendicular to the flow channel that results in several cavitation events. As a result, a vigorous stirring mechanism is induced. We investigate the spatiotemporal dynamics of the spark-generated cavitation bubbles and quantify the created flow disturbance. We demonstrate rapid (in the millisecond timescale) and efficient micromixing (up to 98%) within a length scale of only 200 µm and over a flow rate ranging from 5 to 40 µL/min.


Active mixer Cavitation bubbles Rapid mixing Pocket microfluidics Portable sensors 



The authors thank IIT and Compagnia di San Paolo SIME 2015-0682 for financial support. Microscopy data and images for this study were acquired at NIC@IIT (Nikon Imaging Center) at Istituto Italiano di Tecnologia, Genova, Italy.

Supplementary material

Supplementary material 1 video depicting the mixing process for flow velocity 2.7 mm/s and spark repetition rate 96 Hz (AVI 3237 kb)

10404_2017_1917_MOESM2_ESM.pdf (595 kb)
Supplementary material 2 schematic of the electric circuit used as spark generator (Fig. S1), PIV analysis (Fig. S2), and fluorescence versus dye concentration (Fig. S3) (PDF 594 kb)


  1. Ahmed D, Mao X, Juluri BK, Huang TJ (2009) A fast microfluidic mixer based on acoustically driven sidewall-trapped microbubbles. Microfluid Nanofluidics 7:727–731CrossRefGoogle Scholar
  2. Ballard M, Owen D, Mills ZG et al (2016) Orbiting magnetic microbeads enable rapid microfluidic mixing. Microfluid Nanofluidics 20:88CrossRefGoogle Scholar
  3. Brennen CE (1995) Cavitation and bubble dynamics. Oxford University Press, New YorkGoogle Scholar
  4. Bruggeman P, Ribežl E, Maslani A et al (2009) Non-thermal plasmas in and in contact with liquids. J Phys D Appl Phys 42:053001/1-28Google Scholar
  5. Buchegger W, Wagner C, Lendl B et al (2011) A highly uniform lamination micromixer with wedge shaped inlet channels for time resolved infrared spectroscopy. Microfluid Nanofluidics 10:889–897CrossRefGoogle Scholar
  6. Chan KLA, Niu X, de Mello AJ, Kazarian SG (2010) Rapid prototyping of microfluidic devices for integrating with FT-IR spectroscopic imaging. Lab Chip 10:2170–2174CrossRefGoogle Scholar
  7. Chen CK, Cho CC (2008) Electrokinetically driven flow mixing utilizing chaotic electric fields. Microfluid Nanofluidics 5:785–793CrossRefGoogle Scholar
  8. Dijkink R, Ohl C-D (2008) Laser-induced cavitation based micropump. Lab Chip 8:1676–1681CrossRefGoogle Scholar
  9. Dittrich PS, Tachikawa K, Manz A (2006) Micro total analysis systems. Latest advancements and trends. Anal Chem 78:3887–3908CrossRefGoogle Scholar
  10. Duocastella M, Fernández-Pradas JM, Morenza JL, Serra P (2009) Time-resolved imaging of the laser forward transfer of liquids. J Appl Phys 106:084907CrossRefGoogle Scholar
  11. Duocastella M, Florian C, Serra P, Diaspro A (2015) Sub-wavelength laser nanopatterning using droplet lenses. Sci Rep 5:16199CrossRefGoogle Scholar
  12. Elvira KS, Casadevall i Solvas X, Wootton RCR, de Mello AJ (2013) The past, present and potential for microfluidic reactor technology in chemical synthesis. Nat Chem 5:905–915CrossRefGoogle Scholar
  13. Hai-lang Z, Shi-jun H (1996) Viscosity and density of water + sodium chloride + potassium chloride solutions at 298.15 K. J Chem Eng Data 41:516–520CrossRefGoogle Scholar
  14. Hellman AN, Rau KR, Yoon HH et al (2007) Laser-induced mixing in microfluidic channels. Anal Chem 79:4484–4492CrossRefGoogle Scholar
  15. Jeong GS, Chung S, Kim C-B, Lee S-H (2010) Applications of micromixing technology. Analyst 135:460–473CrossRefGoogle Scholar
  16. Lee CY, Chang CL, Wang YN, Fu LM (2011) Microfluidic mixing: a review. Int J Mol Sci 12:3263–3287CrossRefGoogle Scholar
  17. Luong T-D, Phan V-N, Nguyen N-T (2010) High-throughput micromixers based on acoustic streaming induced by surface acoustic wave. Microfluid Nanofluidics 10:1–7Google Scholar
  18. Nguyen N-T (2012) Micromixers: fundamental, design and fabrication, 2nd edn. William, AndrewGoogle Scholar
  19. Ozcelik A, Ahmed D, Xie Y et al (2014) An acoustofluidic micromixer via bubble inception and cavitation from microchannel sidewalls. Anal Chem 86:5083–5088CrossRefGoogle Scholar
  20. Park S-Y, Wu T-H, Chen Y et al (2011) High-speed droplet generation on demand driven by pulse laser-induced cavitation. Lab Chip 11:1010–1012CrossRefGoogle Scholar
  21. Qian J, Joshi RP, Schamiloglu E et al (2006) Analysis of polarity effects in the electrical. J Phys D Appl Phys 39:359–369CrossRefGoogle Scholar
  22. Qin D, Xia Y, Whitesides GM (2010) Soft lithography for micro- and nanoscale patterning. Nat Protoc 5:491–502CrossRefGoogle Scholar
  23. Sasaki N, Kitamori T, Kim H-B (2006) AC electroosmotic micromixer for chemical processing in a microchannel. Lab Chip 6:550–554CrossRefGoogle Scholar
  24. Schindelin J, Arganda-Carreras I, Frise E et al (2012) Fiji: an open-source platform for biological-image analysis. Nat Methods 9:676–682CrossRefGoogle Scholar
  25. Schönfeld F, Hessel V, Hofmann C (2004) An optimised split-and-recombine micro-mixer with uniform chaotic mixing. Lab Chip 4:65–69CrossRefGoogle Scholar
  26. Sigurdson M, Wang D, Meinhart CD (2005) Electrothermal stirring for heterogeneous immunoassays. Lab Chip 5:1366–1373CrossRefGoogle Scholar
  27. Singh AK, Ko D-H, Vishwakarma NK et al (2016) Micro-total envelope system with silicon nanowire separator for safe carcinogenic chemistry. Nat Commun 7:10741CrossRefGoogle Scholar
  28. Song H, Cai Z, Noh HM, Bennett DJ (2010) Chaotic mixing in microchannels via low frequency switching transverse electroosmotic flow generated on integrated microelectrodes. Lab Chip 10:734–740CrossRefGoogle Scholar
  29. Stroock AD, Dertinger SKW, Ajdari A et al (2002) Chaotic mixer for microchannels. Science 295:647–651CrossRefGoogle Scholar
  30. Suh YK, Kang S (2010) A review on mixing in microfluidics. Micromachines 1:82–111CrossRefGoogle Scholar
  31. Sundararajan P, Stroock AD (2012) Transport phenomena in chaotic laminar flows. Annu Rev Chem Biomol Eng 3:473–496CrossRefGoogle Scholar
  32. Therriault D, White SR, Lewis JA (2003) Chaotic mixing in three-dimensional microvascular networks fabricated by direct-write assembly. Nat Mater 2:265–271CrossRefGoogle Scholar
  33. Wen CY, Yeh CP, Tsai CH, Fu LM (2009) Rapid magnetic microfluidic mixer utilizing AC electromagnetic field. Electrophoresis 30:4179–4186CrossRefGoogle Scholar
  34. Yaralioglu GG, Wygant IO, Marentis TC, Khuri-Yakub BT (2004) Ultrasonic mixing in microfluidic channels using integrated transducers. Anal Chem 76:3694–3698CrossRefGoogle Scholar
  35. Zwaan E, Le Gac S, Tsuji K, Ohl CD (2007) Controlled cavitation in microfluidic systems. Phys Rev Lett 98:22–25CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.Nanophysics DepartmentIstituto Italiano di TecnologiaGenoaItaly

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