GHz Bulk-Acoustic-Wave Resonator Actuated Handheld Ultra-Centrifugal Chip

This study presents a minimized ultra-centrifugal chip featured with high throughput and precise separation for small nanoparticles (<; 500 nm). A bulk acoustic wave (BAW) resonator array is developed to merge with microfluidics and work as the actuation component. Benefit from the gigahertz frequency, the BAW resonators can efficiently trigger strong vortices to trap micro/nano particles from flowing samples. This chip has been experimentally demonstrated with the ability to efficiently separate nanoparticle as small as 200 nm from the sample flow of 20 μL/min. Furthermore, the trapping efficiency of different particle sizes can be precisely tuned that enables size-dependent separation of nanoparticles. The developed chip realizes the small nanoparticle separation by one on-palm device instead of the on-desk huge and expensive centrifugal instrument, and would contribute to the development of point-of-care biomedical applications.