Microfluidic switch based on combined effect of hydrodynamics and electroosmosis
Wong, Teck Neng
Date of Issue2011
School of Mechanical and Aerospace Engineering
This paper presents theoretical and experimental investigations on valveless microfluidic switch using the coupled effect of hydrodynamics and electroosmosis. Switching of a non-conducting fluid stream is demonstrated. The first part of the investigation focused on flow switching of a non-conducting fluid, while the second part focused on switching of aqueous liquid droplets in a continuous oil stream. Two sheath streams (aqueous NaCl and glycerol) and a sample stream (silicon oil) are introduced by syringe pumps to flow side by side in a straight rectangular microchannel. External electric fields are applied on the two sheath streams. The switching process using electroosmotic effect for different flow rate and viscosity of sample stream is investigated. The results indicate that the switching response time is affected by the electric fields, flow rate, and viscosity of the sample. At constant inlet volumetric flow rates, the sample streams or droplets can be delivered to the desired outlet ports using applied voltages.
Microfluidics and nanofluidics
© 2011 Springer-Verlag. This is the author created version of a work that has been peer reviewed and accepted for publication by Microfluidics and nanofluidics, Springer-Verlag. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: http://dx.doi.org/10.1007/s10404-010-0725-x.