Improved Carrier Medium Exchange Efficiency in Acoustic Standing Wave Particle Washing

In English A microfluidic device for particle washing was designed utilizing an acoustic standing wave field in a micro channel. Particles were focused in the center of the channel by the acoustic radiation force while the original carrier media was shifted sideways (orthogonal to the flow) at a number of consecutive wash fluid flow junctions along the main flow. Experiments were carried out in order to compare the washing efficiency to that of an earlier presented particle washing device. The new wash chip removed more than 95% of the original carrier fluid in a mix of 5μm polyamide beads and green food color as compared to the older device which removed only 60% at the corresponding conditions. The particle wash performance was shown to depend on the number of consecutive wash fluid flow junctions.