Mixing and Microfluidics Using Arrays of Shaped Posts


This approach is suceptible to blockage (Image source – Reference 1)This approach is suceptible to blockage (Image source – Reference 1)Mixing liquids in microfluidic channels is difficult and typically requires using chips specifically designed for this purpose. We previously discussed the approach demonstrated by the Whitesides Group (Harvard University) and the Ligler Group (Naval Research Laboratory and North Carolina State). Their approach requires patterning the microfluidic channel floor (or any wall(s) for that matter) with relatively deep chevrons or grooves. This is rather difficult to achieve using the photolithographic technics commonly used to fabricate microfluidic chips. Consequently various alternate schemes have been proposed. One common approach is to create an array of shaped posts in a microfluidic channel, thus forcing the liquid to move sideways or even backward, in order to facilitate fluid mixing. While this approach may promote good mixing, it is susceptible to blockage by contaminants that may be present in the fluid. Consequently, we recommend that you take into consideration possible blockage before using this type of design.



- Microfluidics and Mixing - Introduction

- Microfluidics Mixing Using Ridges & Chevrons



1) "Don’t be baffled by static mixers”, T. Bayer, K. Himmler, and V. Hessel, Chemical Engineering , pp. 2–9, (2003)