Since the group wanted to prove that the technique could be used to print out biological tissue, they experimented with 3D structures:
The researchers' most recent version of acoustic tweezers involves a microfluidic device that uses acoustic wave generators to produce sound waves along the edges of the device. The device's design allowed researchers to manipulate where the waves would meet along each of the three axes. At these meeting points, the waves formed a 3-D trapping node that captured individual cells. The researchers could then further manipulate the acoustic waves to move and place cells.
That microfluidic device can also pick up groups of cells and lay them down again in a preselected pattern, say, to create different types of tissues for specific organs. Seeing as these acoustic tweezers can do these without damaging cells, the team believes it has loads of potential applications. Its ability to prepare cells and tissues for bioprinting could eventually be used in the fields of biomanufacturing, cancer metastasis, regenerative medicine and tissue engineering.