Manipulation of microparticles using surface acoustic wave in microfluidic systems: a brief review

Manipulation of microparticles, which include engineering particles, droplets and cells, has gained attention in various research fields that use microfluidic devices, such as biochemical analyses and clinical diagnosis. Among the microparticle manipulation techniques, microparticle separation has become particularly critical for continuous flow-based analysis, including biochemical assay and clinical diagnosis. Recently, microparticle manipulation techniques using single surface acoustic wave (SAW) or multiple SAWs, namely standing surface acoustic waves (SSAWs) have gained attention in microfluidics because they are non-invasive, label-free, and easy to integrate into microfluidic circuits. This review paper focuses foremost on the most recent advances and application of SAW-driven microparticle separation in microfluidics, and presents analytical models for acoustic separation in microparticle suspension. In addition, recent developments in SAW-driven microparticle manipulation are categorized according to their applications and discussed.