Techniques that can noninvasively and dexterously manipulate cells and other bioparticles in a compact system are invaluable for many applications in life sciences and medicine. The past two decades have witnessed the emerging of acoustofluidics: the fusion of acoustics and microfluidics, due to it numerous advantages such as biocompatibility, miniaturization with lost cost, compatibility with other microfluidic system, and many others. Here, we first demonstrate surface acoustic wave (SAW) enabled acoustic tweezers platform for on-chip particle manipulation. Surface acoustic wave is a kind of ultrasound wave that propagates on the surface of a substrate. By tuning the standing SAW field, we demonstrated the functions of: (1) manipulation of nanoparticles, cells, and C elegance; (2) label free cell separation; (3) multichannel cell/droplet sorting, and (4) tunable cell patterning. Cells viability and proliferation assays were also conducted to confirm the non-invasiveness of our technique. The simple structure/setup of these acoustic tweezers can be integrated with a small radio-frequency power supply and basic electronics to function as a fully integrated, portable, and inexpensive cell-manipulation system. We believe that these unique advantages and functions position our acoustic tweezers to be a useful tool in medical diagnostics and biological/chemical studies.
