Fast acoustic tweezers for the two-dimensional manipulation of individual particles in microfluidic channels

TL;DR

This paper introduces a microfluidic device utilizing standing surface acoustic waves for precise two-dimensional manipulation of individual particles, enabling controlled, rapid, and transparent handling suitable for automation in lab-on-a-chip applications.

Contribution

It presents a novel acoustic tweezers device that achieves controlled 2D particle manipulation with high speed and optical transparency, advancing lab-on-a-chip technologies.

Findings

Particles can be moved at velocities up to 10-20 mm/s.

The device allows precise 2D control of individual particles.

Optical transparency facilitates integration with microscopy.

Abstract

This paper presents a microfluidic device that implements standing surface acoustic waves in order to handle single cells, droplets, and generally particles. The particles are moved in a very controlled manner by the two-dimensional drifting of a standing wave array, using a slight frequency modulation of two ultrasound emitters around their resonance. These acoustic tweezers allow any type of motion at velocities up to few 10mm/s, while the device transparency is adapted for optical studies. The possibility of automation provides a critical step in the development of lab-on-a-chip cell sorters and it should find applications in biology, chemistry, and engineering domains.