Development and characterisation of acoustofluidic devices using detachable electrodes made from PCB.

Acoustofluidics has been increasingly applied in biology, medicine and chemistry due to its versatility in manipulating fluids, cells and nano-/micro-particles. Reducing cost and time for manufacturing surface acoustic wave (SAW)-based acoustofluidic devices could facilitate rapid applications of the SAW technology and attract more researchers into this field. We present herein a novel but simple technology to form a cost-effective SAW device by stacking electrodes made from printed circuit board (PCB) and piezoelectric substrate to generate acoustic waves. PCB-based SAW devices (PCB-SAW) have been characterized and compared to the conventional SAW devices made using the cleanroom fabrication processes. The PCB-SAW devices were successfully used to manipulate microparticles within droplets and microchannels, which showed similar performance with those previously achieved using the standard SAW devices. The PCB-SAW was further used as an acoustic tweezer to precisely pattern the human lung cancer cells inside the microchannel. Cell viability tests proved that the PCB-SAW possessed good biocompatibility to be potentially applied as a cost-effective and precise tool for acoustophoresis and beyond.