AN "acoustic centrifuge" could be used to separate blood samples in a safer and cheaper way. Conventional centrifuges spin around very fast, pulling heavier particles down to the bottom of a sample - a method which probably dates back to Roman times. The Wavecomb system needs no moving parts and relies on ultrasound to sort particles of different sizes.
"It means that the vessels don't have to withstand high-gravity conditions," says John Schram, who is helping to develop the technology. So Wavecomb can separate blood samples while they are still in the thin plastic bags that they are commonly collected in. These sachets would burst in a normal centrifuge.
The Wavecomb system is based on the Kundt Tube, first reported in 1874. A fluid-filled tube was made to resonate, creating an acoustic standing wave inside. Dust particles in the tube gathered at the nodes of the wave. Wavecomb extends the ...
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