Abstract
The feasibility of particle trapping in an acoustic vortex has been theoretically validated. The low frequency, long working distance, and single-beam configuration provide superior usefulness compared with those of conventional standing-wave acoustic tweezers particularly in drug delivery applications. This study experimentally validated the feasibility of acoustic-vortex trap for manipulation of microbubbles (MBs) that were used as ultrasound contrast agents and drug delivery carriers. The trapping characteristics may be useful to increase the efficiency of MBs accumulation at targeted disease areas.