Microfluidics Labs Using Devices Fabricated By Soft-Lithographic Replication of Scotch-Tape Molds

We present the use of Scotch tape to fabricate microfluidic devices in basic teaching labs of high schools and colleges; this technique is an alternative to using photoresist in a cleanroom.Microfluidic devices, beyond their multiple applications as portable, biomedical, analytical labs on a chip, provide the opportunity to creating fluidic environments dominated by viscous and capillary forces.Those microfluidic environments provide educational opportunities to enlighten the unintuitive effects of fluid flows governed by low Reynolds numbers and capillarity.Often, access to a cleanroom and to conventional technologies of microfabrication is limited in high schools and teaching-intensive colleges.We have developed a technique that allows the fabrication of microfluidic devices using bench top tools only: Scotch tape, scalpel, 65C oven, glass slides, commercial uncured silicone-poly(dimethylsiloxane) or PDMS,-and polystyrene Petri dishes (or another suitable container).First we patterned Scotch tape (adhered to a glass slide) with the scalpel.The tape patterns (without the need of any chemical treatment) were then casted in PDMS, yielding microfluidic devices with a height of ~ 60 m-or multiples of 60 m, if several layers of tape were stacked.This technology makes it possible to create microfluidic devices with any planar (2D) design that the students can draw on a paper.After the drawing is finished, it takes only 1 hour to fabricate a microfluidic device with the shape of that drawing.We believe that this technique will enable the study of microfluidics in educational settings limited in their access to cleanroom facilities.We present a demonstrator that illustrates the potential of this technique in standard teaching labs.