Microfluidic devices have been described as “computer chips with plumbing.” But could microfluidics actually be used for computation? Manu Prakash thinks so. As a student in Neil Gershenfeld’s lab at MIT, Prakash developed a system of microfluidic devices that use bubbles to perform Boolean logic functions (e.g., AND/OR/NOT) normally seen in electronic circuits. Since graduating with a PhD in 2008, Prakash has been busy as a member of the Harvard Society of Fellows and will be starting a lab of his own next year to further explore what can be done with bubble logic.
We have invented a new logic family which implements universal Boolean logic, bistability and numerous other traits associated with a scalable logic family using immiscible fluids in microfluidic geometries. A bubble in a channel represents a bit. But unlike electronics, a bit of information can also carry a chemical payload, allowing us to manipulate materials and information at the same time. This paradigm ties together chemistry and computation.
Prakash is not the only one working on microbubbles/microdroplets, but his work is especially compelling because of the link between microfluidics and the huge intellectual toolkit that already exists around computation. A PubMed search on “microfluidic droplet” turns up over 350 entries, Raindance Technologies has been developing droplet technology for years, anddroplets were the theme at the recent CfBI Microfluidics Consortium meeting in March — all indicators that microdroplets/bubble logic are a technology to keep watching.
For more on Prakash’s work:
Media Lab website about bubble logic
Microfluidic Bubble Logic, Manu Prakash and Neil Gershenfeld, Science (Feb. 2007)
2007 Scientific American article “Tiny Bubbles Turn Microscopic Tubing into Liquid Computer”