Binary acoustic trapping in a glass capillary

Abstract Acoustic trapping is a useful method for handling biological samples in microfluidic systems. The aim of this work twofold: first to investigate the physics behind acoustic glass capillary and secondly perform binary trapping. latter achieved by increasing density fluid channel. device consisted with rectangular inner cross-section (height 200 µ m × width 2000 m) equipped small piezoelectric transducer. transducer was actuated at 4 MHz generate localised half-wavelength standing-wave-field capillary, comprising pressure field velocity field. Under actuation, only particles higher than fluid, i.e. having positive dipole scattering coefficient, were trapped flow direction. numerical analytical modelling system show that force which retains against depends on coefficient nodal plane model also reveals retention proportional agrees our experimental findings. Next, we showed mixture melamine polystyrene high-density it possible selectively trap particles, since have particles.