Cristian Soitu, Alexander Feuerborn, Ann Na Tan, Henry Walker, Pat A. Walsh, Alfonso A. Castrejon-Pita,
Peter R. Cook, and Edmond J. Walsh.
Microfluidic chambers using fluid walls for cell biology
PNAS June 12, 2018. 201805449; published ahead of print June 12, 2018
Despite improvements in our ability to manipulate ever-smaller volumes, most workflows in cell biology still use volumes of many microliters. We describe a method for creating microfluidic arrangements containing submicroliter volumes. It exploits interfacial forces dominant at the microscale to confine liquids with fluid (not solid) walls. We demonstrate many basic manipulations required for cell culture and some widely used downstream workflows. The method eliminates many problems associated with the fabrication of conventional microfluidic devices, thereby providing a simple on-demand approach for fabrication of microfluidic devices using materials familiar to biologists. pdfRead More
Walsh, E., Feuerborn, A., Wheeler, J., Tan A.N., Durham W., Foster K., and Cook, P.R. (2017).
Microfluidics with fluid walls.
Nature Communications 8, Article number: 816 (2017) doi:10.1038/s41467-017-00846-4
Microfluidics has great potential, but the complexity of fabricating and operating devices has limited its use. Here we describe a method — Freestyle Fluidics — that overcomes many key limitations. In this method, liquids are confined by fluid (not solid) walls. Aqueous circuits with any 2D shape are printed in seconds on plastic or glass Petri dishes; then, interfacial forces pin liquids to substrates, and overlaying an immiscible liquid prevents evaporation. Confining fluid walls are pliant and resilient; they self-heal when liquids are pipetted through them. We drive flow through a wide range of circuits passively by manipulating surface tension and hydrostatic pressure, and actively using external pumps. Finally, we validate the technology with two challenging applications — triggering an inflammatory response in human cells and chemotaxis in bacterial biofilms. This approach provides a powerful and versatile alternative to traditional microfluidics. pdfRead More