Figure 1.

Microacoustic viability separation. The chip uses acoustophoresis to achieve label-free, high-throughput separation of viable and nonviable mammalian cells. A mixture (light blue) of viable (white) and nonviable (black) mammalian cells and a stream of suspension buffer (dark blue) are injected into the device via separate inlets at a 1:3 flow-rate ratio. The resulting colaminar flow keeps the cells close to the walls of the separation channel. Piezoelectric actuation generates an acoustic radiation force that preferentially focuses larger, viable cells toward the acoustic pressure node within the center streamline, enabling these cells to exit via the collection outlet. This force is insufficient to focus the smaller, nonviable cells to the center streamline, and they exit the device via the waste outlet.