Continuous particle size separation and size sorting using ultrasound in a microchannel

Continuous separation and size sorting of particles and blood cells suspended in a microchannel flow due to an acoustic force are investigated both numerically and experimentally. Good agreement in the measured particle trajectories in a microchannel flow subjected to the acoustic force with those obtained by the numerical simulations up to the fitting parameter is found. High separation efficiency, particularly in a three-stage microdevice (up to 99.975%), for particles and blood cells leads us to believe that the device can be developed into commercially useful set-up. The novel particle size sorting microdevice provides an opportunity to replace rather expensive existing devices based on specific chemical bonding with an ultrasound cell size sorter that can be considerably improved by adding many stages for multistage size sorting.