Particle concentration and mixing in microdrops driven by focused surface acoustic waves

By R. Shilton, M. Tan, Leslie Y. Yeo, James R. Friend. 2008

302 citations recorded by the source corpus.

We report the use of focused surface acoustic waves (SAWs) generated on 128° rotated Y-cut X-propagating lithium niobate (LiNbO3) for enhancing the actuation of fluids and the manipulation of particle suspensions at microscale dimensions. In particular, we demonstrate increased efficiency and speed in carrying out particle concentration/separation and in generating intense micromixing in microliter drops within which acoustic streaming is induced due to the focused SAW beneath the drop. Concentric circular and elliptical single-phase unidirectional transducers (SPUDTs) were used to focus the SAW. We benchmark our results against a straight SPUDT which does not cause focusing of the SAW. Due to the increased wave intensity and asymmetry of the wave, we found both circular and elliptical SPUDTs concentrate particles in under 1 s, which is one order of magnitude faster than the straight SPUDT and several orders of magnitude faster than conventional microscale devices. The concentric circular SPUDT was found ...

Subfields: Biomedical Engineering

View Paper: https://www.semanticscholar.org/paper/4cbaaa30fb50090a26e27e309b1dfcfc72a12c8f

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Biomedical Engineering

1. Leslie Y. Yeo
2. James R. Friend
3. Sourav Banerjee
4. Debdyuti Mandal
5. Nam-Trung Nguyen

Citations in the corpus

• Microscale acoustofluidics: Microfluidics driven via acoustics and ultrasonics (2011, methodology): “There are a variety of focusing designs, including elliptical and circular structures, that give different focal patterns of acoustic waves, which in itself can be useful (Shilton et al., 2008).”
• Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications (2022, background): “The selection of a suitable sensing membrane involves several factors such as good selectivity of the target molecules or analytes, high response, stability, low-cost, and most of all, good biocompatibility with low toxicity [165].”
• Surface Acoustic Wave Microfluidics (2014, methodology): “At the high-power extreme, strong constant streaming within the drop causes either the dispersion or concentration of the colloids (Li et al. 2007b, Shilton et al. 2008), discussed in Section 3.”
• High-throughput micromixers based on acoustic streaming induced by surface acoustic wave (2011, methodology): “In droplet-based micromixer, SAW has been demonstrated as a driving and disturbance source for rapid mixing [11–14].”