Acoustic tweezers are based on focused acoustic vortices and hold promise to precisely manipulate microorganisms and cells from the millimeter scale down to the submicron scale, without contact, and with unprecedented selectivity and trapping force. The widespread use of the technique is hindered at present by limitations to the existing systems stemming from performance, miniaturization and the inability to assimilate in compartments. In a recent study, Michael Baudoin and colleagues at the Sorbonne University and the French National Center for Scientific Research (CNRS), improved the potential of focused acoustic vortices by developing the first flat, compact and paired single electrode focalized or focused 'acoustical tweezer'.
The invention relied on spiraling transducers that were engineered by folding a spherical acoustic vortex on a flat piezoelectric substrate. Baudoin et al. demonstrated the ability of these acoustic tweezers to grab and displace micrometric objects within a microfluidic environment with unique selectivity. The system is simple and scalable to higher frequencies; opening tremendous perspectives in microbiology, microrobotics and microscopy. The results are now published in Science Advances.
Observations - Levitation - Wave - Fields - Date
The first reported observations of partial levitation in acoustic wave fields date back to the work of Boyle and Lehmann in 1925. Precise and contactless manipulation of physical and biological objects at the micrometer scale down to the nanometer scale has promising applications in the modern, diverse fields of microrobotics, tissue engineering and micro/nanomedicine. Acoustic tweezers are a prominent technology to accomplish the task as they are noninvasive, biocompatible and label-free. They are also able to trap forces that are several orders of magnitude larger than their optical counterparts, at the same actuation power. However, only recently have scientists simultaneously developed advanced wave synthesis systems, microfluidic setups and the theory of acoustic radiation pressure, to allow the potential of acoustophoresis (motion with sound) to be harnessed.
Until recently a majority...
Wake Up To Breaking News!