Do-it-yourself microfluidics and possibilities for micro PIV

Abstract

We present a method for microfluidic channel fabrication that has the following advantages compared to conventionally-used methods: technical simplicity, dramatically lower fabrication costs, and fabrication time. The method entails printing channel designs on a thermoplastic film from a LaserJet printer. Exposure to high temperatures elicits isotropic shrinkage of the film (in the x-y plane), in addition to thickening (in the z-direction), resulting in a positive relief mold. The microfluidic channel design of the mold is then transferred to a polydimethyl siloxane (PDMS) chip through soft lithography, resulting in a ready-to-use microfluidic chip. Through this approach, chips with complex channel geometries can be generated with low cost equipment and in as little as a couple hours. Flow visualizations from several chips from the 'Do-it-yourself Microfluidics Workshop', held at the Faculty of Mechanical Engineering Univeristy of Belgrade, are presented in this paper. We also discuss possibilities for adapting micro particle image velocimetry (PIV) measurements to channel designs on PDMS-based microfluidic chips using the fabrication method delineated here.

Keywords

• microfabrication
• microfluidics
• shrinky dink
• rapid prototyping
• pdms
• micro piv