In recent years, biochemical laboratories have shrunk thanks to a technology called microfluidics. This is the ability to pump liquids though tiny labyrinthine corridors carved into silica chips and then to mix, react and separate them on a microscopic scale. So techniques that previously required an entire lab bench can be done on a microscopic scale using a microfluidics chip.
These plastic chips contain complex warrens of corridors, pumps, mixing chambers, assay areas and the like. But sitting on top of these plastic chips are integrated circuits that switch pumps on and off, and open and close corridors and so on. This circuitry is the brains of the microfluidics chip and the need to incorporate this electronic machinery and fluid mechanics significantly increases the complexity of the devices.
Now that looks set to change thanks to the work of Daniel Case at Northwestern University and colleagues. The team has found a way to control, switch or even reverse the flow in these corridors without any electronic control.
