Martin Z. Bazant (Chemical Engineering and Mathematics)
   Todd Thorsen (Mechanical Engineering)

   Chien-Chih Huang (Applied Math and Mech. Eng.)

   Damian Burch (Applied Mathematics)
   Xiaochuan Yang (Chemical Engineering)

   Armand Ajdari (ESPCI, Paris)
   Todd Squires (UCSB)
   Brian Storey (Olin College)
   Orlin Velev (NC State)

   Mustafa Sabri Kilic (PhD Applied Mathematics 2008)
   John Paul Urbanski (PhD Mechanical Engineering 2008)
   Jeremy A. Levitan (PhD Mechanical Engineering 2005)
   Kevin Chu (PhD Applied Math 2005)
   Yuxing Ben (Postdoc 2004-2005)
   Jakub Kominiarczuk (BS Physics 2007)
   Matt Fishburn, Brian Wheeler, Andrew Jones (UROP)

100 micron/sec ICEO flow around a 25 micron gold post
in a polymer microchannel driven by a 300 Hz 100 V/cm
electric field from an experiment by J. Levitan. (Movie available below.)


We are broadly interested in developing novel methods of manipulating fluids and particles in microdevices using electric and/or magnetic fields. Our focus has been on nonlinear electrokinetics, specifically induced-charge electro-osmosis (ICEO) at metal surfaces and electrode arrays, and the related effect of induced-charge electrophoresis (ICEP) of polarizable colloidal particles. We have also begun to study concentration polarization and other nonlinear electrokinetic phenomena. Our work is grounded in fundamental mathematical theory and involves close coordination with experiments at MIT and elsewhere. At MIT, our main focus is on developing new portable or implantable microfluidic devices, operating at low voltage and low power by nonlinear electrokinetics. We are pursuing various applications in biotechnology, such as implantable drug infusion pumps and portable medical diagnostic devices.



Simulation of 3D ACEO flow around stepped electrodes (by Yuxing Ben). Top: the electric field in phase with the AC forcing at the optimal pumping frequency. Bottom: The time-averaged streamlines showing the "fluid conveyor belt" which allows fast pumping. [Bazant & Ben, Lab on a Chip (2006).]

SEM image of a 3D ACEO pump, consisting of a periodic array of interdigitated stepped gold microelectrodes on a glass substrate (by J.P. Urbanski). Experiments confirm an order of magnitude increase in flow rate versus standard planar ACEO pumps, but also reveal a double-peaked frequency spectrum and flow reversal, not predicted by the standard theory. [Urbanski et al., Applied Physics Letters (2006).] Our latest devices, with theoretically optimized geometries [Burch & Bazant 2008] achieve > mm/sec velocities and 1 % atm pressure in water with only 1 Volt rms without flow reversal, and have been applied to DNA microarrays. [Huang, Bazant, Thorsen 2009]



The slides from these public lectures are available online, subject to the copyright restrictions below.


    Induced-Charge Electro-osmosis

  1. Induced-charge electro-kinetic phenomena: Theory and microfluidic applications, M. Z. Bazant and T. M. Squires, Phys. Rev. Lett. 92, art. no. 066101 (2004). This paper triggered a Fast Moving Front of research. (Thompson Scientific.) (PDF)
  2. Induced-charge electro-osmosis, T. M. Squires and M. Z. Bazant, J. Fluid. Mech. 509, 217-252 (2004). (PDF)
  3. Experimental observation of induced-charge electro-osmosis around a metal wire in a microchannel, J. A. Levitan, S. Devasenathipathy, V. Studer, Y. Ben, T. Thorsen, T. M. Squires, and M. Z. Bazant, Colloids and Surfaces A 267, 122-132 (2005). (PDF)
  4. Electrostatic and electrokinetic contributions to the elastic moduli of a driven membrane, D. Lacoste, G. I. Menon, M. Z. Bazant, and J. F. Joanny, European Physical Journal E 28, 243-264 (2009). (PDF)
  5. Nonlinear electrokinetics at large voltages, M. Z. Bazant, M. S. Kilic, B. Storey, and A. Ajdari, New Journal of Physics 11, 075016 (2009). (PDF)
  6. Towards an understanding of nonlinear electrokinetics at large applied voltages, M. Z. Bazant, M S Kilic, B Storey, and A Ajdari, Advances in Colloid and Interface Science 152, 48-88 (2009). (PDF)
  7. Effective zero-thickness model for a conductive membrane driven by an electric field, F. Ziebert, M. Z. Bazant, and D. Lacoste, submitted.
  8. Induced-Charge Electrophoresis

  9. Breaking symmetries in induced-charge electro-osmosis and electrophoresis, T. M. Squires and M. Z. Bazant, J. Fluid Mech. 560 65-101 (2006). (PDF)
  10. Induced-charge electrophoresis of metallo-dielectric particles, S. Gangwal, O. J. Cayre, M. Z. Bazant, and O. D. Velev, Phys. Rev. Lett. 100, 058302 (2008). (PDF)
  11. Induced-charge electrophoresis near an insulating wall, M. S. Kilic and M. Z. Bazant. (PDF)
  12. Electro-osmotic Micropumps

  13. Theoretical prediction of fast 3D AC electro-osmotic pumps, M. Z. Bazant and Y. Ben, Lab on a Chip, 6, 1455-1461 (2006). (PDF)
  14. Fast AC electro-osmotic pumps with non-planar electrodes, J. P. Urbanski, T. Thorsen, J. A. Levitan, and M. Z. Bazant, Applied Physics Letters 89, 143508 (2006). (PDF)
  15. The effect of step height on the performance of AC electro-osmotic microfluidic pumps, J. P. Urbanski, J. A. Levitan, D. N. Burch, T. Thorsen, and M. Z. Bazant, Journal of Interface and Colloid Science 309, 332-341 (2007). (PDF)
  16. Electrolyte dependence of AC electro-osmosis, M. Z. Bazant, J. P. Urbanski, J. A. Levitan, K. Subramanian, M. S. Kilic, A. Jones, and T. Thorsen, Proceedings of MicroTAS, Paris (2007). (PDF)
  17. Experimental study of electrolyte dependence of AC electro-osmotic pumps, K. Subramanian, J. P. Urbanski, J. A. Levitan, T. Thorsen, and M. Z. Bazant, Proceedings of the International Conference on Micro, Meso, and Nanoengineering, Trivandrum, India (2007). (PDF)
  18. Steric effects on ac electro-osmosis in dilute electrolytes, B. Storey, L. R. Edwards, M. S. Kilic, and M. Z. Bazant, Phys. Rev. E 77, 036317 (2008). (PDF)
  19. Design principle for improved three-dimensional ac electro-osmotic pumps, D. Burch and M. Z. Bazant, Phys. Rev. E 77, 055303(R) (2008). (PDF)
  20. Numerical studies of nonlinear kinetics in induced-charge electro-osmosis, M. M. Gregersen, M. Z. Bazant, and H. Bruus, XXII ICTAM Proceedings, Adelaide, Australia (2008). (PDF)
  21. Topology and shape optimization of induced-charge electro-osmotic micropumps M M Gregersen, F Okkels, M Z Bazant, and H Bruus, New Journal of Physics 11, 075019 (2009) . (PDF)
  22. Ultrafast high-pressure AC electro-osmotic micropumps for portable biomedic al microfluidics, C. C. Huang, M. Z. Bazant, and T. Thorsen, Lab on a Chip 10, 8 0-85 (2010). (PDF)


  23. Induced-charge electrokinetic phenomena, M. Z. Bazant and T. M. Squires, Current Opinion in Colloid and Interface Science, to appear. (PDF)
  24. Nonlinear electrokinetic phenomena, M. Z. Bazant, in Li, Dongqing (ed), Encyclopedia of Microfluidics and Nanofluidics, Part 14, pp. 1461-1470 (Springer, Berlin, Heidelberg, New York, 2008). (PDF)
  25. AC Electro-osmotic flow, M. Z. Bazant, in Li, Dongqing (ed), Encyclopedia of Microfluidics and Nanofluidics, Part I, pp. 8-14 (Springer, Berlin, Heidelberg, New York, 2008). ( PDF)
  26. Electrokinetic motion of polarizable particles , M. Z. Bazant, in Li, Dongqing (ed), Encyclopedia of Microfluidics and Nanofluidics, Part 5, pp. 522-529 (Springer, Berlin, Heidelberg, New York, 2008). ( PDF)
  27. Electrokinetic motion of heterogeneous particles, M. Z. Bazant, in Li, Dongqing (ed), Enc yclopedia of Microfluidics and Nanofluidics, Part 5, pp. 518-522 (Springer, Berlin, Heidelberg, New York, 2008). (PDF)
  28. Ph.D. Theses

  29. J. A. Levitan,Experimental Investigation of Induced-Charge Electro-osmosis, Doctoral Thesis in Mechanical Engineering, MIT (2005).
  30. K. T. Chu, Asymptotic Analysis of Extreme Electrochemical Transport, Doctoral Thesis in Applied Mathematics, MIT (2005).
  31. Mustafa Sabri Kilic, Induced-charge electrokinetics at large voltages. Doctoral Thesis in Applied Mathematics, MIT (2008).


  32. M.I.T. Case # 9576 - T. M. Squires and M. Z. Bazant, Microfluidic pumps and mixers driven by induced-charge electro-osmosis, US Patent 10/319,949 issued in 2006, filed in 2002. International Patent PCT/US02/40290.
  33. M.I.T. Case # 11683 - J. A. Levitan, T. Thorsen, M. Schmidt, and M. Z. Bazant, Microfluidic pumps and mixers driven by induced-charge electro-osmosis, US Patent Application 11/252,871 filed in 2005.
  34. M.I.T. Cases #12056, 12057, 12058 (combined into one patent) - M. Z. Bazant, Y. Ben, J. A. Levitan, and J. P. Urbanski, Induced-charge electro-osmotic microfluidic devices, US Patent Application 11/700/949, filed in 2007.
  35. M.I.T. Case #12513 - M. Z. Bazant and J. A. Levitan, Temporal modulation of electrokinetic pumps for mixing applications, US Patent Application, filed in 2007.
  36. M.I.T. Case #12639 - M. Z. Bazant, Induced-charge electrokinetics with high-slip polarizable surfaces, US Patent Application 60/996/245 filed in 2007.
  37. M.I.T. Case # 12949T - M. Prakash and M. Z. Bazant, Multiphase microfluidic devices, 2009.


We gratefully acknowledge support from the following organizations:


Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation or the US Army.


All of the materials above (preprints, movies, and presentations) are subject to Copyright held by the authors and are available only for personal or educational use with proper citation.

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