ABSTRACT
Ultrasonic standingwaves canbeused to generate radiation forces on particles suspending in fluid.The force has a number of potential applications in microfluidic devices, such as separation [1, 2, 3], positioning [4, 5], washing [6] and assaying [7, 8, 9] of bio-functionalized particles or cells. Most of the previously reported miro-machined systems are based on one-dimensional ultrasonic fields.
