Single microparticle manipulation by an ultrasound microbeam

Optical tweezers, which have limited applications sometimes, have been employed in various fields. Acoustic trapping was suggested as an alternative tool. It was previously shown that a 30 MHz ultrasound microbeam device (acoustic tweezer) could trap a 120 μm lipid particle in water. In order to find more practical applications for this device, typically in cell mechanics, the trapped particle size must be further reduced. The final distance in which the particle could no longer be attracted was identified as the maximum displacement. The mean maximum displacement of the trapped particle was 50.4 μm at 16 V_PP, while it was 55.4 μm at 22 V_PP. Experimental results demonstrated the trapping of lipid particles as small as 50 μm, much smaller than previously accomplished.