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Title: Contactless, programmable acoustofluidic manipulation of objects on water
Contact-free manipulation of small objects ( e.g. , cells, tissues, and droplets) using acoustic waves eliminates physical contact with structures and undesired surface adsorption. Pioneering acoustic-based, contact-free manipulation techniques ( e.g. , acoustic levitation) enable programmable manipulation but are limited by evaporation, bulky transducers, and inefficient acoustic coupling in air. Herein, we report an acoustofluidic mechanism for the contactless manipulation of small objects on water. A hollow-square-shaped interdigital transducer (IDT) is fabricated on lithium niobate (LiNbO 3 ), immersed in water and used as a sound source to generate acoustic waves and as a micropump to pump fluid in the ± x and ± y orthogonal directions. As a result, objects which float adjacent to the excited IDT can be pushed unidirectionally (horizontally) in ± x and ± y following the directed acoustic wave propagation. A fluidic processor was developed by patterning IDT units in a 6-by-6 array. We demonstrate contactless, programmable manipulation on water of oil droplets and zebrafish larvae. This acoustofluidic-based manipulation opens avenues for the contactless, programmable processing of materials and small biosamples.  more » « less
Award ID(s):
1807601
PAR ID:
10172984
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Lab on a Chip
Volume:
19
Issue:
20
ISSN:
1473-0197
Page Range / eLocation ID:
3397 to 3404
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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